Bio 102 Lab Manual Questions

Exercise 1: The Microscope
Page 4
Letter “e” Observation
The letter “e” should appear upside down and backwards. Under high magnification,
you will see only part of the“e” and may see dots of ink rather than a continuous flow of
ink.
Crossed Threads Observation-Describe your observations
Under low (4x) power: Two of the threads are almost in focus, but it is impossible to get
both completely focused at the same time. By focusing first on 1 thread then on the
second, it is possible to judge which thread is on top. This is an example of being able
to visualize in 3-D.
Under 10x power, you still have some depth perception and can see the threads
crossing over each other although you are seeing a smaller area of threads and may
need to move the stage to see more of the threads.
Under 40x power, you lose all depth perception and are unable to determine which
thread is on top and which is on the bottom. You are seeing smaller areas of the thread
because of the higher magnification.
Under which power was it easiest to get the overlapping threads mostly in focus?
Low power

Page 6
Study Questions
1. Summarize the function of the following parts of the microscope:

a. Nosepiece: Holds objective leases
b. Iris diaphragm: Constricts or dilates to allow varying amounts of light to pass
through the slide

c. Coarse adjustment: Focusing knob, usually the large one, that allows you to
focus your slide more quickly. Use with low power only otherwise you may
damage the slide or the lens.

2. What does the term “parfocal” mean?
The microscope is designed so that when you switch to the higher objective lens,
the microscope will automatically be partially focused. You will only need minor
adjustments of the fine adjustment knob.
3. Why is it important to start with the lowest power objective lens?
This is the magnification under which it is easiest to find your focus quickly using
the coarse adjustment knob. At low magnification, your depth of field is best so
the precision required for focusing is less.
4. What is the total magnification of your specimen if you are using a 10x ocular
and a 45x high-dry objective lens?
10 x 45x = 450x
5. Your lab partner accidently bumps your microscope and you have lost your
focus. What should you do in order to find your specimen again?
You should begin again with the low power (4x) objective lens.
6. Why should you center the part of your slide you need to view when switching
to a higher power objective lens?
Higher magnification focuses on a smaller area. If the specimen is not centered,
you won’t see it in the smaller area of focus available with the higher
magnification.
7. Refer back to the crossed threads slide. What have you learned about depth
perception and the microscope?
Low magnification gives a greater sense of dimension. You needed to move the
slide around under higher magnification in order to see all the threads. It was
very difficult to judge which thread was on top in the higher magnifications.

Exercise 2: Cell Anatomy
Page 12
Study Questions
1. Supply the names of the cell organelles that fit the following descriptions:
a.
b.
c.
d.
e.
f.
g.
h.

Control box of the cell; contains DNA and chromosomes: Nucleus
Cell suicide sacs with enzymes: lysosomes
Workshop of the cell; they build proteins: ribosomes
Two short, rodlike structures that compose the centrosome:
centrioles
Outer cell boundary with pores: plasma cell membrane
Tubular network of membranes throughout the cytoplasm:
endoplasmic reticulum
Potato or peanut shaped powerhouses of the cell: mitochondria
Stack of flattened membranes nicknamed the cell packaging plant:
Golgi apparatus

2. Name five cell structures that can be observed with your high-dry objective
lens:
1. plasma membrane
2. nucleus
3. nucleolus
4. cilia
5. flagellum (sperm
6. Cytoplasm with unspecified organelle
7. chromatin
3. Name five cell organelles that would be visible only with an electron
microscope:
1.
2.
3.
4.
5.
6.

Golgi apparatus
mitochondria
ribosomes
lysosomes
centrioles
endoplasmic reticulum

4. List 3 statements in the cell theory:
1.
2.
3.

The cell is the smallest living system capable of maintaining itself.
All cells come from pre-existing cells.
All organisms are composed of cells.

5. What are the functions of cilia and flagella in the human body?
Both work to produce motion – either of materials, as in ciliated epithelium, or of
the cell as in the sperm’s flagellum.
6. List the 4 cell types you observed and give a brief description of their structure
as it relates to their functions:
1.
Sperm: small & flagellated for movement
2.
Ciliated epithelium: larger cell with many cilia for movement of dirt
particles out of the respiratory system.
3.
Striated muscle: very long, thick cell that can contract & cause movement.
4.
Motor neuron: very long, slender cell that can carry information over great
distances.
7. Name the 3 basic parts of a sperm cell.
1.
head (consisting of an acrosome & nucleus)
2.
neck
3.
flagellum (or tail)
8. How are striated muscle cells different in appearance from typical animal
cells?
Striated muscle cells are many times longer than typical animal cells & they are
multinucleated.

Exercise 3: Body Terminology, Planes and Cavities
Page 19
1. Supply the proper term to match each definition
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
2.

Lying horizontal on your belly with your dorsal side up prone
Below or beneath inferior
Belly or undersurface ventral
Having 2 sides alike bilateral symmetry
Standing erect, face view, with at least one palm forward
anatomical position
The front end or an animal anterior
The head end of an animal cranial
Leading to the outside external
Near or next to proximal
The rear or tail end of an animal caudal

Name these body planes:
a.
“Cross cut” through a body part transverse
b.
Longitudinal plane dividing body into anterior and posterior halves
frontal
c.
Longitudinal plane dividing body into right and left halves sagittal

3. Interpret this lab description: “Make a ventral, superficial, median incision
from anterior to posterior through the skin of your fetal pig.”
On the belly side (ventral) make a shallow (superficial) incision cutting the skin
along the midline (median) from the front end near the neck (anterior or cephalic
end) to the bottom end below the umbilical cord (caudal or tail end).
*Note: This description would be slightly different for humans since
anterior/posterior means front to back instead of head to tail as it does in the pig.
4. List 5 major organs found within the abdominal cavity:
1.
Stomach
2.
Small intestine
3.
Large intestine (except the rectum)
4.
Pancreas
5.
Spleen
6. Liver

7. gallbladder
8. any abdominal blood vessels
9. kidneys (technically found retroperitoneally)
5. List 3 organs found in the pelvic cavity.
1. Urinary bladder
2. Urethra
3. Rectum
4. Uterus
6. Name 5 organs within the thoracic cavity.
1. Lungs
2. Heart
3. Trachea
4. Esophagus
5. Blood vessels
7. Name the major organ within the:
a. Cranial cavity  brain
b. Spinal cavity  spinal cord
8. Where is the gallbladder located in the pig and in humans?
a & b. The gallbladder fits into a hollow in the liver which is in the abdominal
cavity of both pigs & humans.
9. Why is it important to know about the various body terms, planes, and
cavities, especially at the beginning of your biology course?
You will need to use anatomical terminology in any biology & anatomy courses
you take. This terminology is also extensively used in all health and medical
professions.
10. Describe a median sagitall incision through an organ:
It is a longitudinal cut along the midline of the organ which separates the organ
into equal left and right halves.
11. List 4 characteristics unique to mammals:
1.
warm blooded
2.
mammary glands
3.
4 chambered heart
4.
body hair

12. Give another name for the mediastinal cavity.
Interpleural cavity
13. Name 3 organs within the mediastinal cavity.
1.
heart
2.
trachea
3.
esophagus

Exercise 4: The Tissues
Page 22
Name several organs. What are their functions? Discuss with the class what
tissues these organs might be composed of. Place your answers below.

1. Heart

Organs

Function
pump blood

Tissues
cardiac muscle and fibrous
connective tissue

2. Lungs

exchange gases

3. Trachea

carries air

simple squamous
epithelium and elastic
connective tissue
hyaline cartilage and
ciliated columnar epithelium

4. Small Intestine

digests/absorbs

1. smooth muscle and simple

5. Pancreas

produces energy

2. cuboidal epithelial tissue

columnar epithelium
6. Large intestine
7. Liver
8. Stomach

and loose connective tissue
absorbs water
3. smooth muscle and
columnar epithelial tissue
process nutrients and
4. smooth muscle and
wastes
cuboidal epithelial tissue
Digestion and absorption 5. smooth muscle and simple
columnar tissue

Name several organ systems. What organs are part of these systems, and what
is the major function of each system?
System
Organs
Function
1. Circulatory
Heart, blood vessels
Transports chemicals to all
body cells
2. Urinary
Kidneys, bladder
Removes metabolic waste,
regulates fluids and solutes
3. Nervous
Brain, spinal cord, nerves
Controls sensation,
communication, respiration
4. Digestive
Stomach, small intestine,
Digests and absorbs
large intestine
nutrients
5. Respiratory
Trachea, lungs
Exchanges gases

Page 23

How is simple squamous epithelium adapted to diffusion, filtration and osmosis?
It is a single layer of flat cells so it provides the thinnest possible barrier across which
gases, nutrients wastes can easily travel.

Page 24
How is columnar epithelium adapted to secretion?
1. The volume of cell is large relative to its surface area.
What is the role of cilia in the respiratory system?
2. It removes small, unfiltered dust particles from the respiratory tract.

Page 25
Epithelial Tissue
Squamous
Cuboidal
Columnar

Sketch

Function
Diffusion or filtration
Secretion &
absorption
Secretion &
absorption

Location
Lungs, kidneys,
capillaries
Glands(salivary),
kidney tubules
Stomach, small
intestine

Page 26
1. What is the arrangement of cells in Hyaline Cartilage?
Cells are spaced apart in small cavities called lacunas.
2. What is the nature of the matrix in this tissue?
It is composed of tightly packed collagen fibers that are smooth and solid, but
flexible.
1. Describe the arrangement of cells and fibers in areolar tissue.
Fibers are randomly arranged and cells are widely scattered.
2. Do all cells and fibers in this tissue look the same?

Fibers are different-some are thin. reticular fibers & some are thick collagen fibers .
Others are wavy elastic fibers.
3. What type of matrix does this tissue form?
The matrix is thinner & more fluid than in other tissues. The cells are indistinct &
appear as dark dots of varying size.

Page 27
Adipose Tissue
1. Does this tissue have a matrix? No.
2. This tissue provides a function like one of the other tissues. What function
and which tissue?
Adipose tissue provides loose padding similar to areolar connective tissue. The
padding & insulation provided by fat in adipose tissue is better than in areolar
connective tissue
3. Where is fat stored in this tissue?
The fat is stored in large fat vacuoles within each cell.

Dense White Fibrous Connective Tissue
1. What is the arrangement of fibers in this tissue?
The fibers are parallel to each other.
2. Can you see this tissue’s matrix?
You can see densely packed collagen fibers & an occasional fibroblast.

Page 28 Chart 4.2
Tissue
Epithelial
Hyaline cartilage

Sketch

Function
Forms linings
Protection, flexible
connection

Location
Inside or outside lining of
all organs
Rib cartilage; cartilage at
ends of long bones which
form a moveable joint

Areolar
Adipose
Dense white fibrous

Loose packaging
material
Insulates, cushions,
stores energy
Strong connection

Under skin, around organs
Subcutaneous fat
Tendons

EXERCISE 5-THE INTEGUMENTARY SYSTEM
p. 32
1. Observe the model of skin and identify all of the structures mentioned in the
discussion.
arrector pili muscle
basement membrane
epidermis
dermis
free nerve ending
hair follicle
hair root
hair shaft
Meissner's corpuscle
Pacinian corpuscle
sebaceous (oil) gland
stratum corneum
stratum lucidum
stratum granulosum
stratum spinosum
stratum basale
sudoriferous (sweat) gland
2. Observe the slide of the skin. Identify the structures described in the
discussion. Do they differ from the model, photograph and drawing?
A slide is typically a random slice through a small piece of skin. It is two-dimensional
and shows a view through a structure, rather than from the side of something. It is
unlikely to have all of the structures found on the model.
4. Based on the slide, indicate how it differs from the model and Figure 5.1.
Answers will vary based upon the specific model you are looking at. However, the
model and the slide are different because the model is in three dimensions, and
most of the structures in it will appear whole. In the slide, the structures are
sectioned.
5. Why do the structures look different from the model?
Slides are 2-dimensional, and models are 3-dimensional. The explanations below
talk about some specific differences:
a. Consider the sweat gland. As you can see on p. 30, the sweat gland appears as a
coiled duct. However, under the microscope it appears as several clusters of
cuboidal cells. This is because the slide provides a cross-section, and the coiled
duct is cut through in many places. You would see the same thing if you cut across a
knot.

b. The direction of the cut (as opposed to the type of cut) may also make a slide look
very different from a model, and a hair follicle is a good example of this. Imagine
making a vertical (longitudinal) cut through a banana. The section would look like a
long white structure surrounded by a thin strip of yellowish peal on the sides. A hair
follicle would look like this if cut longitudinally. The hair follicle's cuboidal cells might
be found along the sides of a long yellow or brown hair. Now imagine making a
transverse (crosswise) cut of the banana. You would see pieces that look circular or
oval with a thin strip of yellowish peel all the way around. A hair follicle may look like
a circle or an oval of cuboidal cells with a round piece of yellow or brown hair inside
if cut through in cross section.
c. Some structures are just too small or indistinct to be able to see them on a slide.
While you should be able to see all of the structures identified in this chapter on the
model, with the microscopes available in lab, you would only be able to recognize
the following on the microscope slide: Hair follicles and sebaceous glands on a scalp
slide; the five layers of the epidermis on a Meissner's corpuscle slide; Pacinian
corpuscle on a Pacinian corpuscle slide; and sweat glands may be visible as several
clumps of small cuboidal cells on any of the slides mentioned. It takes a lot of
experience to be able to identify blood vessels, Meissner's corpuscles, and other
nerve endings on a slide.

Exercise 6: The Skeletal System
Page 43-44
1. Outline the 2 major divisions of the human skeleton.
Axial skull, vertebral column, rib cage
Appendicular shoulder girdle, arms; pelvic girdle, hips, legs
2. Define the following:
a. Diaphysis hollow shaft of long bone
b. Epiphysis ends of long bone
c. Medullary cavityhollow-area of diaphysis; contains yellow or red bone marrow
d. Osteocyte bone cell in mature bone tissue; located in lacuna
e. Lacuna small hollow cavity in which osteocytes are found
3. Give at least 2 major differences between the human male and female pelves.
Female: wider; coccyx is straighter;
Male: narrower; coccyx is curved inward.
4. What are the 2 major types of bone tissues within a whole bone? What are
their functions?
Compact bone is stronger and more dense. It provides support & protection.
Spongy bone is lighter with interwoven threads of bone tissue. It provides the
framework for blood forming tissue
5. In which joint type categories do each of the following belong?
a. Most vertebrae: slightly moveable
b. Sutures: immovable
c. Shoulder—humerus: freely movable; synovial type ball & socket joint
d. Sacroilliac joint: slightly moveable in late pregnancy
e. Knee and elbow: moveable; hinge joint; synovial
6. What is a Haversian system?
It is a nutrient--waste exchange system in compact bone consisting of rings of
osteocytes in lacunas which are joined by canaliculi to Haversian or Central canals
which contain the blood vessels.
7. What is unusual about compact bone and cartilage tissue as compared to
most body tissues?
They are solid tissues and contain a large proportion of non-living martrix compared
to other living cells.

8. Write the anatomical name for the following bones:
a.
Second cervical vertebrae:
axis
b.
Last 2 pairs of ribs:
floating
c.
Vestigial tailbone:
coccyx
d.
Shoulder blade:
scapula
e.
Upper jawbone:
maxilla
9. Name the 3 ear ossicles (bones).
hammer – malleus
Anvil – incus
Stirrup – stapes
10. List at least 4 major functions of the human skeleton:
protection of internal organs
support
mineral storage(calcium)
blood cell formation
provides levers for locomotion

Exercise 7: The Muscular System
Page 50
What are the myofilaments and what is their job in a muscle cell?
The myofilaments are actin & myosin. Myosin uses energy to pull actin protein fibers to
the center of the sarcomere in order to shorten & contract the muscle cell.

Match the listed movement with the term that best describes its action.
____1___ A. Extension

___2____ C. Flexion

____4__ B. Rotation

___3____ D. Abduction

1. Starting with your chin on your chest, raise your head to look straight ahead.
2. Cross your arms in front of your chest.
3. Sitting with arms at your side and shoulders facing the table, reach for your
textbook on the table.
4. Placing your arm out straight, alternate the “thumbs up, thumbs down”
position.

Page 55
1. Intramuscular injections are typically given in the shoulder and buttocks
areas. Which muscles are injected?
Deltoid and Gluteus maximus
2. Which muscle is the prime mover for eack of the following movements?
Winking: Orbicularis oculi
Shaking your head “no”: Sternocleidomastoid (SCM)
Hugging: Pectoralis major
Jumping: Quadriceps femoris and/or gastrocnemius

Page 56
Experiment 1

4. Explain your results.
When you are working hard, the muscle depletes its oxygen supply. The blood
flow to the muscle increases to replace the lost oxygen. Stressed muscle may
force its cells to switch to anaerobic respiration which causes lactic acid
formation. Lactic acid dilates blood vessels entering the muscle causing the
engorgement of muscle with blood.

Experiment II
3. Which average was higher (the first or second)? Why?
The second average should be higher. This is called the “warm up” effect. The
enzymes involved in muscle contraction work more effectively at elevated
temperatures (sarcoplasmic reticulum calcium levels also tend to be higher)

Part B
5. Which average was the lowest? Third
Why? It is demonstrating fatigue. Depleted ATP energy reserves lessen the strength of
the contractions regardless of how intensely the nervous system stimulates the muscle
to contract.

Page 57
Chart 7.1
Muscle Cell General
Type
Appearance
Skeletal
Long, threadlike,
multinucleated
Smooth
Short, unstriated
spindle shaped
Cardiac
Striated, branched,
interconnected

Location
Quadriceps
Internal
organs
Heart

Voluntary/
Involuntary
Voluntary

Fast or Slow

Involuntary

slow

Involuntary

Moderately fast,
very efficient

fast

2. Name the smallest contractile unit of striated muscle. The sarcomere.
3. Make a sketch of a sarcomere and label at least 5 items.
Possible items to label:
Actin
Myosin
Sarcoplasmic reticulum
Sarcolemma
Nucleus
Mitochondria
A-band

I-band
Z-line
Myofibrils
4. Briefly explain what happens when a muscle contracts.
Myosin uses energy stored in ATP to pull actin fibers closer together. This shortens
the length of the sarcomere & in turn shortens (contracts) the whole muscle cell.
5. Define tonus.
A mild state of contraction due to alternate contraction of different motor units. Tonus
is especially important in maintaining posture.
7. Which type of muscle does not consist of fiberlike cells? Smooth
8. Fill in the term that best fits the description given:
a. Moves a joint toward the midline of the body:
Adduction
b. Raises a body part:
Levator
c. Protein that composes the thick filament:
Myosin
d. Any muscle that bends or decreases the angle of a joint: Flexion
e. Tension applied without shortening:
Isometric
f. Muscular stiffness due to death:
Rigor mortis
g. Mild state of contraction for most muscles:
Tonus
9. Name the muscles described below:
a. Shoulder muscle that abducts the arm:
deltoid
b. Large diamond shaped muscle that extends the head:
trapezius
c. Two muscles involved in chewing:
masseter & temporalis
d. Posterior humerus muscle that extends the forearm:
triceps
e. Large middle back muscle that adducts and extends the arm: latissimus
dorsi
f. Calf muscle that extends (points) the foot:
gastrocnemius
10. Name the 2 muscle groups that move the lower leg and state their main
actions:
hamstrings flex the lower leg;
quadriceps femoris extends the lower leg

Exercise 8: NERVOUS SYSTEM
Page 61
How might this affect the neuron?
The neuron can’t undergo mitosis. This is part of reason destroyed neurons can’t
be replaced.
Page 63
2. Look at the slide of neurons labeled “ox smear.”
a) Which structures are easily identified? The cell body and the nucleus.
b) Which structures cannot be seen on the slide?
The internal organelles, the Schwann cells and the myelin. The axons and the
dendrites are visible but can’t be differentiated from each other.
c) Why can’t you see all of the named structures?
The internal organelles are too small to be seen with a light microscope.
(These require an electron microscope.)
3. Look at the demonstration slide of a medullated (myelinated) neuron and
explain what you see.
The slide is rarely clear and distinct. You should be able to see axons surrounded by
myelin and Schwann cells. (It should look like a beaded necklace)
Page 64
Where else is fluid used in a similar manner? (Hint: think pregnancy).
Amniotic fluid

Page 66
What is the effect of severing the spinal cord?
It disrupts communication between the brain and all spinal nerves below the damaged
area. The body parts affected display paralysis and a total absence of sensation.
What is the effect of severing the ventral root? Movement and perhaps glandular
activity are disrupted. Sensation is still intact.

What is the effect of severing both roots? The same as severing a spinal nerve.
Page 67
The ventral root has motor function only. It is composed of axons only. Where
are the cell bodies of these axons?
They are inside the gray matter of the spinal cord.
Page 70
3. Since the subject is a mature adult, what would you expect to occur with an
infant?
A positive Babinski demonstrated by a backward fanning of the toes.
What does this tell you about the direction of myelination?
Myelination spreads from the CNS to the periphery of the body.
Can you force an infant to walk at a younger age?
No, they don’t have the rapid nerve impulse transmission and gross motor
coordination provided by myelination of motor neurons serving these muscles.
Do all infants develop at the same rate? No
What evidence would you offer for your answer?
A range is given for walking and pincer grip. Most babies walk between 10 – 14
months.
Alcoholics with polyneuritis and people with multiple sclerosis exhibit a positive
Babinski reflex. What type of damage has occurred to the spinal cord?
There has been damage to the myelin sheath of the nerves.
Study Questions:
1. Name and describe the three structural types of neurons. Indicate the major
type of function of each type.
Multipolar: an axon with many dendrites attached to the cell body. It’s usually
functions as a motor neuron or an interneuron.
Bipolar: has 2 processes which are attached to either side of the cell body. They
are sensory and are very rare.
Unipolar: Has one projection which attaches the cell body to the axon. They are
usually sensory.
2. Identify the organs forming the central nervous system.
The brain and the spinal cord

3. Identify the structures forming the peripheral nervous system.
Ganglia, spinal nerves, cranial nerves. Some texts may also include the
receptors as part of the peripheral nervous system.
Page 71
5. What is a node of Ranvier? It is a small gap of exposed axon between Schwann
cells on a myelinated axon.
6. Name the structure essential for axon regeneration.
The neurilemma (outermost cell membrane) of the Schwann cell. It produces
growth factors and serves as a tunnel or guide for regrowth of a nerve. The neuron cell
body must also be alive.
7. Identify the meninges. What are their collective functions?
They are a connective tissue wrapping which encloses the brain & spinal cord. The
duramater is the tough outermost layer. The arachnoid mater is the loose middle
layer which forms space for the cerebrospinal fluid. The pia mater is the innermost,
delicate layer with direct contact with the CNS. These layers protect CNS structures.
8. What is cerebrospinal fluid (CSF)? How is it formed and where is it found?
What are its functions?
It is a thin liquid formed from the reatively high pressure in the blood vessels
called the chorioid plexus. It provides shock absorption and nutrition to all areas which
are covered by the liquid.
9. Which spinal root has the cell bodies of the sensory neurons?
The dorsal root.
10. A spinal tap is performed at the level of which vertebrae? Why? (Use your
text to find the answer.)
The lower lumbar region since the spinal cord ends at the level of L1 and only the
cauda equina is present distal to this level. Since the cauda equina is a collection of
nerves rather than a thick, solid cord of tissue, it is less likely that a needle would
puncture or damage nerve tissue.
11. Name the three connective tissue wrappings of the nerve and indicate what
they wrap.
The endoneurium: wraps directly around the neuron. The perineurium wraps around
a bundle of neurons called a fascicle. The epineurium wraps the entire nerve.

12. Name the spinal plexuses and the major nerves emerging from each plexus.
Spinal Plexus
Nerve
cervical:
phrenic nerve
brachial
radial & ulnar nerves
lumbar:
femoral
sacral:
sciatic nerve
13. List the structural components of the reflex arc.
The receptor is the sensory neuron which receives the stimulation. The impulse
travels to the spinal cord which is the integration center. In a monosynaptic
reflex, the impulse is sent directly to a motor neuron and from there to the effector
–the muscle or gland which produces a response. In a polysnaptic reflex, there
is an interneuron or association neuron in the spinal cord which routes the impulse
to both the brain and the motor neuron to the effector.

EXERCISE 9-NERVOUS SYSTEM II
Page 79
Was the subject responsive to all of the above tests? If not, indicate which he or
she couldn’t carry out and what the implication might be.
A healthy person with no disabilities should be able to perform all of the tests in table
9.1. Inability could be due to either dmage to the nerve or the body part served by
the nerve.
Which nerve descends into the abdominopelvic and thoracic cavities?
The vagus nerve.
Page 82--Study Questions:
1. List three functions of the cerebrum.
Initiation of motor function; receipt of sensory information;processing of
information into a response (intelligence)
2. What is the function of the cerebellum?
It coordinates motor control.
3. List the functions of the medulla.
It regulates basic life support functions including respiration, cardiac and
vasomotor control.

4. List the functions of the hypothalamus.
It regulates body temperature and management of the endocrine system.
5. Identify the cranial nerves that are involved in eye movements.

oculomotor (IV); trochlear (IV); and abducens nerves (VI)
6. Identify the cranial nerve which is involved in equilibrium.
The vestibulocochlear (also called the auditory) nerve (VIII)
7. This cranial nerve regulates head movement: spinal accessory (XI) nerve
8. Which division of the ANS would be involved in the beating of your heart when
you are calm and relaxed?
The Parasympathetic Nervous System
9. Identify some sympathetic responses to stress and indicate how they prepare
you for coping with the stressful situation.
An increased heart rate increases your blood pressure to ensure sufficient blood
flow to the brain and muscles. It stimulates the sweat glands (to keep you cool
during fight/flight); it dilates bronchial tubes to increase oxygen supply to the blood
and it redirects the blood flow to skeletal muscles (rather than the digestive system)

10. Why is exercise beneficial to someone with asthma whose bronchi are
constricted?
Sympathetic responses enhanced by exercise tend to constrict systemic blood
vessels but dilate bronchial tubes. This reverses the effect of asthma’s constriction.
11. Why might stress raise blood pressure?
It activates the sympathetic division which will constrict blood vessels and thus raise
blood pressure.
12. Why shouldn’t an athlete eat a large meal prior to participating in an athletic
activity?
After a large meal, the Parasympathericl Nervous System stimulates an increase in
blood flow directly to the digestive organs which makes it difficult to increase blood
pressure and blood flow to muscles. If muscles are deprived of blood flow, cramps
or spasm may result. Once the sympathetic nervous system response is activated,
it cuts off the blood supply to the digestive structures, thus causing these structures,
which are full of food, to cramp which causes pain.
13. Is the stress response appropriate to the type of stressful situations one
encounters in modern life? If so, why?
The stress response evolved to help us escape predators and deal with life and
death situations. Most stressful situations don’t usually require an active physical
response (vs. an emotional response) so the increased blood pressure and other
aspects of the stress response may be harmful over time. (Police and firemen,
soldiers need an intense sympathetic response due to job requirements.)

EXERCISE 10-THE SENSES
Page 85
Which tactile receptors did you learn about when you studied the skin? What
were their functions?
Pacinian (pressure) & Meissner’s (light touch) corpuscles
1. Dip a moistened swab into sugar and touch the tip of your tongue with the
swab. (Your tongue must be moist – not dry.) Do you taste the sweetness?
Sweet taste receptors generally are found near the tip of your tongue, but you may
also find a slight sweet response on the sides of the tongue especially if sugar is
placed anteriorly.
3. Repeat the above procedure for salt. Where do you sense the strongest salty
taste?
Salt taste receptors are usually found on the sides of the tongue.
4. Use your textbook to look up the location of the various taste receptors of the
tongue and list them below.
Bitter receptors are at the back of the tongue; sweet is at the front of the tongue;
salty & sour are at sides of the tongue
5. Are taste chemoreceptors specific to categories of chemicals? Explain your
answer and your results.
Yes taste chemoreceptors are specific. Since we can’t taste except as indicated
above, the receptors must be specific.
Page 86
6. Propose an explanation for the pattern of tactile receptor density you obtained
for the human body.
The higher density of tactile receptors would enhance the accuracy of two point
discrimination . So, a higher density of receptors would be found in our fingertips
and hands. This helps us manipulate materials and tools which require accurate
sensory feedback.
3. Explain how the subject’s receptors were working during this experiment?
The receptors were detecting minute changes in stress placed on their joints.
Page 88
What structures of the eye translate light energy into nervous impulses during
the day?
Cones translate light energy into nervous impulses and provide color vision during
the day.

At night? Rods are more sensitive at night but do not permit color vision.
What do you think causes color blindness?
Loss or malfunction of one or more varieties of cones.
Page 90
4. What does the term “20/20 vision” really mean?
When standing about 20 feet away from the chart, the person is able to read the last
line as accurately as a person with normal vision would be able to read it from 40
feet away.
Why is it more difficult to place the pencil in the tube with one eye closed?
You are no longer using binocular vision. (The point of this experiment is that most
people should have more success using both eyes since binocular vision enhances
the brain’s ability to interpret depth (depth perception).
Observe the color blindness tests on display. Does seeing how these tests are
designed to help you answer the earlier question on the cause of color
blindness? If so, revise your explanation regarding the cause of color blindness.
Color blindness tests are usually designed such that it would be impossible to see
the image provided without the ability to visually separate 2 or more colors. So,
color blindness is simply the loss or malfunction of one or more varieties of cones.
Page 91
Name, in order, the structures involved in the conduction of sound from the pinna
to the brain.
pinna → auditory canal or meatus → tympanic membrane → malleus →incus
→ stapes → oval window → cochlea → organ of Corti → vestibularcochlear
nerve → temporal lobe of the brain
What kind of receptors are used to produce your sense of hearing?
hair cells (a kind of mechanoreceptor)
What “organ” in the inner ear translates vibrations into nervous impulses?
The Organ of Corti
Page 92
Why do you think we have three semicircular canals?
These correspond to the 3 planes of space. Regardless of which direction we move,
there is always 1 canal partially oriented to the direction of movement.
2. Repeat placing the tuning fork several times in random order. Where was your
partner least able to localize the position of the sound source?
_____________________

Propose a reason for this.
The only positions where lateralization would be consistently accurate should be
laterally. Because they arrive a split second sooner, the brain interprets sound as
being louder in the ear that is closer to the source of the sound. This may be why
we turn our head to one side when having difficulty localizing a sound.
Bone Conduction
Your hearing pathway is designed to magnify sound and bring the sound vibrations
directly to the appropriate part of the cochlea. Directly vibrating the skull near the
cochlea may be the only way to vibrate the cochlea if there is damage to the
conduction pathway. So, when sound decreases in front of the pinna, you should
not be able to hear the fork when placed on the mastoid process.
Work in pairs. Have your partner close his or her eyes and place a tuning fork
near either ear. Strike a tuning fork of a different frequency near the same ear.
Did your partner correctly identify the second tuning fork as making a sound with
a higher or lower pitch? ___ Did both sounds stimulate the same hair cells in
the cochlea? Explain.
Vibrations of fluid in the vestibular and tympanic canals occurs in the same
frequency as the original sound waves. Fibers of the basilar membrane have
different lengths at different regions of the cochlea; sound waves convert to
vibrations of the basilar membrane in a location specific manner according to tone.
Considering that balancing requires a great deal of motor coordination (recall the
role of the cerebellum), what does this experiment prove about the sense of
balance?
It reminds you that along with the ears, visual input and the work of cerebellum in
motor coordination are also important in helping the brain maintain balance. The
cerebellum relies on at least 3 different forms of sensory feedback in order to
coordinate movement (including movement important in balance): inner ear balance
feedback; proprioceptor feedback and visual feedback. Loss of any one causes
difficulty in balance.
Page 93
1. List four different kinds of receptors and state their basic function.
photoreceptors: retina – vision;
chemoreceptors: taste buds;
mechanoreceptors/tactile receptors: Meissner’s corpuscles, light touch
pain receptors: pain sensation (thought to be a form of chemoreceptor related to
tissue damage)
2. How is a receptor different from other neurons studied thus far?
They are modified sensory neurons which can trigger an action potential in response
to environmental stimuli instead of neurotransmitters. Most neurons can be
stimulated only by neurotransmitters under normal circumstances in the body.
3. What structures must light pass through before reaching the retina?

cornea → aqueous humor → pupil → vitreous humor →retina
4. What do the terms “20/60 vision” and “20/15 vision” mean/
When standing at 20 feet, the subject reads the last line as correctly as a person
with 20/20 vision would be able to read from 60 feet away.
20/15 means that when standing at 20 feet away, the subject reads the last line as
correctly as a person with 20/20 vision would be able to read from 15 feet away.
5. What is the transparent portion of the sclera called?
The cornea
6. What are the two muscular modifications of the choroid and what are their
jobs?
They are: iris - modifies size of opening through which light enters pupil
ciliary body - modifies tension on (and therefore) shape of the lens
7. Name four items that protect the eye from damage.
The bony socket of skull;
tears which contain antibacterial agents;
reflexes such as blinking
adipose tissue cushion in bony socket.
8. Which light-bending structure can change shape?
lens
What happens when this structure loses its elasticity with age?
Focusing on either very distant or very near objects becomes increasingly difficult;
typically, focusing on near objects becomes more difficult with age.
9. State the basic functions of the inner ear and list the structures involved in
each function.
The inner ear is important for both hearing and balance. The cochlea is specialized
for hearing; the vestibule is specialized for static equilibrium;the semicircular canals
are specialized for dynamic equilibrium.
Page 94
10. Briefly explain the difference between static equilibrium and dynamic
equilibrium.
Static: maintains balance while you are still.
Dynamic: maintains balance while you are moving
11. What structures are common to the hearing and equilibrium functions of the
inner ear?
Hair cell receptors translate vibrations into nervous impulses for hearing and are
also pulled by gravity in the vestibule or pushed by moving fluid in the semicircular
canals and, thus function in balance.

EXERCISE 11-THE ENDOCRINE SYSTEM
Page 103: Study Questions
1. What are the two chemical classes of hormones?
Steroid and amino acid/peptide
2. The hormones released by the posterior pituitary are actually made in the:
hypothalamus
Page 104
3. What are tropic hormones, and where are they made?
Tropic hormones are hormones that control other endocrine glands. They are
made in the anterior pituitary gland
4. Fill in the name for the endocrine portion of each of the following endocrine
glands.
Testis
interstitutal cells
Pancreas Islets of Langerhans
Ovary
follicle & corpus luteum
5. Two endocrine glands discussed in this chapter have both a portion made of
glandular (epithelial) tissue, and a portion made of modified nervous tissue. What
are they?
The pituitary and adrenal glands
Which portions of each gland are made of epithelial tissue?
The anterior pituitary and adrenal cortex
Nervous tissue?
The posterior pituitary and the adrenal medulla
6. Match the endocrine gland with its hormone.
Pancreas _C
a. growth hormone
Anterior pituitary A
b. epinephrine
Ovary D
c. insulin
Adrenal medulla B
d. estrogen
7. Match the hormone with its function.
Glucocorticoids d
a. Stimulates liver cells to break down glycogen
and release glucose
Glucagon a
b. Stimulates smooth muscle contraction in the
uterus during childbirth.
ACTH c
c. Stimulates the adrenal cortex to produce and
release hormones

Oxytocin

b

d. Stimulate cells to produce glucose from other
organic molecules.

8. In terms of both identification and function, what is the difference between an
ovarian follicle and a corpus luteum?
Follicle produces estrogen & appears as a ball of cells containing the egg cell.
Corpus luteum produces progesterone and estrogen and appears as an irregular
yellowish mass of cells.
9. Predict what would happen to a person who was unable to produce ADH.
The person would be unable to reabsorb water from the kidney tubules.
Dehydration would be likely unless the person constantly drank an excessive
amount of water.
10. Predict what would happen to a person who was unable to produce sufficient
thyroid hormone.
Their metabolism would lower decreasing their energy and appetite however the
person would gain weight irregularly.

EXERCISE 12: THE BLOOD
Page 108- Observing Erythrocytes
3. Describe the appearance of the blood elements you are examining.
Erythrocytes appear as biconcave disks; they are thinner & lighter in the center and
thicker at edge. They have no nucleus.
Are the cells the same size or do their sizes differ?
Leukocytes are larger than erythrocytes and have a nucleus. Monocytes are lighter
in color than the other leukocytes.
Page 110 TABLE
Measurement

Normal Value

Total Erythrocyte
count
(number per mm3)

4.5-5.5
million /mm3

Total leukocyte
count
(number per mm3)

5,000-10,000 /mm3

Clinical
Significance Of
Increased Value
polycythemia

Clinical
Significance Of
Decreased Value
anemia

Possible infection

Increased
susceptibility to
infection

Differential count
Neutrophils

65%

Acute infection

Eosinophils

<5%

Parasitic infectipn

Basophils

<1%

Lymphocytes

~ 20%

Monocytes

~ 8%

Allergy or
inflammation
Specific immune
response
Chronic infection

Page 112-Study Questions
1. Look up and define:
a. Polycythemia
b. Leukocytosis
c. Leukopenia
d. Leukemia

If any of these
counts were low,
this would indicate
a possible bone
marrow disorder

high erythrocyte count
Abnormally high leukocyte levels
low leukocyte count
form of bone marrow cancer where a large number of
non-functional leukocytes are produced
2. When en erythrocyte has a shape other than that of a biconcave disk, how
might its function be affected?

There is reduced gas exchange surface, less flexibility with a tendency to clog blood
vessels.
Page 113
3. Considering its function, why is the biconcave disk shape of the RBC superior
to a simple sphere?
Because the disk has more surface area, it is more flexible and allows RBCs to
stack when pushed through narrow vessels.
4. How might the lack of a nucleus be an advantage to the red blood corpuscle?
The space a nucleus would take provides additional volume for hemoglobin to carry
oxygen and makes it easier for the cell to take a biconcave shape.
How might it be a disadvantage?
RBC are unable to reproduce or produce materials necessary for their own
maintenance. This means that RBC have a limited life span.
5. What is the difference between a total leukocyte count and a differential count?
Total count is non-specific with regard to types of leukocytes present and only
indicates if levels are high or low. This information can tell us whether or not there is
an infection or other disorder A differential gives percentages of each type of
leukocyte but not the total leukocyte percentage in whole blood. This provides clues
to the kind of infection or disorder that is likely to be causing illness.
6. Where are RBCs produced? They are produced in the red bone marrow.
WBCs? Platelets? Both are also produced in the red bone marrow.
7. How is blood viscosity related to blood circulation?
Higher viscosity leads to higher resistance. It is difficult to pump thicker blood and this
will affect heart function and blood pressure.
8. What is the danger to an individual with a:
low total white blood cell count? increased susceptibility to infection
high total white blood cell count? possible leukemia or infection
low number of platelets?
impaired blood clotting
low hemoglobin determination? reduced O2 (oxygen) carrying capacity
low red blood corpuscle count? reduced oxygen carrying capacity
high red blood corpuscle count? This is also called polycythemia and it will lead
to increased blood viscosity (thickness)/
9. Why is it dangerous to supply a blood type different than the recipient’s blood
type in a transfusion?
The person’s immune system produces antibodies against foreign blood types.
Antibodies may agglutinate the foreign blood cells leading to potential damage to
cardiovascular system and the kidneys.

EXERCISE 13-THE HEART AND GENERAL CIRCULATION
Page 116
How do veins and arteries differ in structure and function?
Arteries are thicker walled (especially the muscular layer) but have a smaller lumen
than veins. Semilunar valves are present in veins to facilitate venous return to the
heart. Veins have a bigger lumen than arteries.
How does the size and structure of a capillary relate to its function?
The small diameter increases surface contact of blood with the body tissues. The
single layer of squamous cells provides the thinnest possible barrier for diffusion.
Page 119
Why is the heart called a double pump?
Because right and left sides each have separate pumping responsibilities (The left
side pumps oxygenated blood to the aorta and thus to the entire body. The right
side pumps deoxygenated blood to the lungs where the blood picks up oxygen
and is returned to the left side of the heart.
What are the main functions of the valves of the heart?
The valves will prevent any backward flow of blood.
Which blood vessels supply the heart muscle with oxygenated blood?
The coronary arteries
Page 120
3. Have your partner determine your heart rate and record it. Are the rates
acquired using the stethoscope and counting the pulse approximately the same?
They should be same
Explain. The pulse corresponds to the beating of heart. You should get identical
answers.
6. Compare the results obtained by your classmates. Do you discern any
differences between the results of males and females?
Males tend to have slower pulse rates than females. Hower, the level of
conditioning is a stronger determining factor. Better conditioned people have lower
pulse rates regardless of sex.
Page 123
After exercise, what changes did you observe in systolic pressure? In diastolic
pressure? Are these changes you expected? Explain
Both systolic and diastolic pressures increase during exercise and return to baseline
within several minutes.

Diastolic pressure may go down in well conditioned people. The vasodilation of
vessels (which tends to lower blood pressure between heart beats) is a normal
response to elevated pressure. Additionally, lactic acid accumulates in muscles
which dilates blood vessels feeding skeletal muscles. The resulting decrease in
diastolic blood pressure is a homeostatic response to the increased blood pressure
due to the increased muscle activity.
Define systolic blood pressure:
Highest arterial pressure during ventricular systole
Define diastolic blood pressure:
lowest arterial pressure during ventricular diastole
Define hypertension: Abnormally elevated blood pressure
Define hypotension: Abnormally low blood pressure
In your own words, describe the effects of hypertension and hypotension.
Hypertension can damage structures in many body systems including the
cardiovascular and urinary systems and increase the risk of having a stroke. Low
blood pressure can cause dizziness and fainting which could lead to shock.
What would you expect to happen to blood pressure and pulse rate during sleep?
Explain.
Blood pressure should go down due to the lower metabolic demand by most organs.
The lower metabolic demand promotes a slower movement of blood around the
body. The pulse rate also decreases due to the lower metabolic demands.

EXERCISE 14—THE RESPIRATORY SYSTEM
Page 131
4. Notice how your abdomen is pushed outward as the contracted diaphragm
flattens. Describe the position of the contracted diaphragm.
The diaphragm moves in an inferior direction, toward the abdominopelvic cavity, and
flattens as it contracts.
Describe the position of the relaxed diaphragm.
It is pushed superiorly, back into the thoracic cavity, and resumes its rounded or
dome-shape.
How does the position of the diaphragm affect the size of the thoracic cavity?
When the diaphragm is flat (contracted), the volume of the thoracic cavity increases
(therefore it has a lower pressure). When the diaphragm is bell-shaped (rounded),
the volume of the thoracic cavity decreases and it therefore has higher pressure.
Page 132
What could you do to the lung-thorax model to cause the balloons to fill with air?
Pull down on the rubber sheet to increase the volume and lower the pressure inside
the jar. Air moves into the balloons to try to equalize pressure.
7. If the integrity of the pleura is disturbed (such as by a puncture into the chest
wall), what do you think would happen to the lung?
The glass slides represent the pleural membranes. They demonstrate that moist
membranes tend to stick together and this is partially why thoracic cavity expansion
causes lung expansion. A puncture to this cavity would cause a collapsed lung
because it would be impossible for any pressure or volume changes to occur
therefore the lungs would be unable to expand.
CHART 14.2
Bell Jar

Human Body
Equivalent

straight glass tubing

trachea

glass wall of jar

thoracic cavity

rubber sheeting

diaphragm

balloons

lungs

Y-shaped glass tube

primary bronchi

Page 134

1. Exhale through your mouth onto a glass plate or mirror. Your results indicate
that one component of exhaled air is water vapor.
3. What might you conclude causes the change in temperature?
The heavily vascularized respiratory passages.
Page 135 Experiments
The breath holding experiments are supposed to illustrate the role of carbon dioxide and
increased acidity on stimulating the respiratory rate. By decreasing the carbon dioxide
levels (which is what happens when we hyperventilate) we decrease our rate of
respiratory stimulation. By rebreathing in a bag, we increase our carbon dioxide levels
and thus increase our respiratory stimulation.
Page 136
Which activity decreases respiratory rate? Mental acidity decreases the respiratory
rate.
Which activity increases respiratory rate? Exercise
Can you usually speak aloud and inhale simultaneously? No
Can you swallow and breathe simultaneously? No or else the epiglottis would be
open while food or liquids were moving into the pharynx causing airway blockage
and choking.
Propose a reason why prolonged sedentary mental activity might produce a
yawn. (Boredom is not a valid response.)
Since mental activity decreases the respiratory rate, prolonged mental activity allows
CO2 levels to increase. This eventually triggers a deeper inhalation-exhalation cycle
and develops into a yawn.
2. Hold your breath until urge to breathe becomes overwhelming. Do not inspire
but take a small sip of water. What has happened to your urgent need to
breathe?
Swallowing seems to suppress your perceived need to inhale.
STUDY QUESTIONS:
1. Name the anatomical structure located directly behind the trachea.
esophagus
2. Name the membrane that covers the lungs. visceral pleura
3. What is the name for the structure that blocks entry into the larynx during
swallowing?
The epiglottis
4. What is the name given to the groups of air sacs that comprise most of lung
tissue? alveoli

5. What is the Adam’s apple? The thyroid cartilage of the larynx
6. Would it be possible for a healthy child to die by holding its breath? Why?
No, unconsciousness allows the involuntary respiratory centers of the brain stem to
take over and reverses the unconsciousness by causing the child to breathe.
7. Briefly describe the effect of carbon dioxide on breathing.
Carbon dioxide is a strong respiratory stimulant. CO 2 combines with water forming
carbonic acid. Both the increased acidity and increased CO 2 affect chemoreceptors
which stimulate the brain to increase the respiratory rate.
Page 137
8. What effect does exercise have on carbon dioxide production? It increases it.
9. What structures of the respiratory system are involved in the following?
a. Humidifying air
b. Warming air
c. Filtering air

Contact between air and the warm, moist
membranes of the upper respiratory tract
facilitate humidifying, warming, and
filtering of air. Most of this occurs in the
nasal cavity since it contains structures
that increase the surface area for contact
between air, the nasal membranes and the
sinuses. There are also many blood
vessels in the nose to help in warming air.

d. Conducting air

Air is conducted through the nasal cavity,
pharynx, larynx, trachea, primary bronchi,
secondary bronchi, tertiary bronchi,
bronchioles and alveolar ducts.

e. Producing sound

Vocal cords/(folds) in larynx

10. What is the function of the diaphragm?
It causes pressure changes in the thoracic cavity by changing the shape and
volume of the thoracic cavity.
11. What activities can influence breathing?
Conscious control - holding breath or forced breathing; exertion-- increased
muscle use can build up CO2 and acidity within the body; miscellaneous items:
drinks, stress, disease
12. Differentiate cellular respiration and ventilation. (Use a reference text.)
Cellular respiration is a biochemical process converting organic molecular energy
into ATP-stored energy. The cellular process also generates CO 2 under aerobic

conditions. Ventilation is the respiratory system’s breathing process for exchange
of gases.
13. During inhalation is air sucked in or pushed in? Explain:
Air is sucked in. The diaphragm flattens and moves in an inferior direction thus
increasing the volume of the thoracic cavity. This also causes pressure in the
cavity surrounding the lungs to decrease. Air is sucked into the lungs because of
the pressure gradient created. Air moves from higher to lower pressure.
14. Does your chest expand because your lungs inflate, or do your lungs inflate
because your chest expands? Explain:
Lungs inflate because the chest expands. Thoracic/pulmonary expansion causes
the pressure gradient that sucks air in (see above answer.)
15. What structural feature ensures that the trachea will be an open airway?
Cartilagenous C-rings are strong and flexible. They are strong enough to keep the
trachea open but flexible enough to bend rather than break when exposed to stress.

EXERCISE 15-THE DIGESTIVE SYSTEM
Page 140
Give an example of a place in the body where mechanical digestion is performed.
Primarily in the mouth by chewing but also in the stomach by its churning action.
Give an example of a place in the body where chemical digestion is performed.
Nearly all parts of the digestive tract except the esophagus and the large intestine.
The stomach and the small intestine are the main chemical digestion sites.
Consider that the food you eat and the air you filter as you breathe are not sterile.
What other benefit might HCl provide in the stomach?
It kills bacteria and any other infectious agents.
Which category of food molecule (protein, starch, or lipid) has not been broken
down significantly by enzymes by the time food has left the stomach?
Lipids; lipase is only effective at the pH found in the small intestine.
Page 141
What two “nonenzymes” are contributed to the duodenum, and what are their
jobs?
NaHCO3 (sodium bicarbonate) neutralizes acid. Bile which is important for lipid
emulsification.
Would a protease produced by the pancreas or a protease produced by the
stomach work best in an acidic environment?
Pepsin produced by the stomach works best in an acidic environment.
In an alkaline environment? Pancreatic protease, delivered to the small intestine,
work best in an alkaline environment.
Page 142
What parts of the digestive system are not involved with either digestion or
absorption of food?
The esophagus and large intestine. (Large intestine absorbs H 2O and vitamins.)
What are their functions?
Esophagus works to transport food to the stomach. Large intestine absorbs H 2O &
vitamins made by bacteria.
Page 144
Compare the approximate length and diameter of the small and large intestine.
Which is longer? The small intestine

Which is larger in diameter? The large intestine
Why is the small intestine so named?
Because it is smaller in diameter than the large intestine.
Page 145
Compare the 850-Calorie estimate with your experimental results for a cup of
peanuts. Is there any significant difference between the two numbers?
The experimental results should be different.
If so, how much higher or lower? Typically less than half of the 850 Calorie estimate
Page 146
Give two reasons for any possible difference between your experimental results
and the estimate given by a diet book.
a) The human body is more efficient than fire at extracting chemical energy from a
peanut.
b) Experimental error; some of the heat is lost to the air so not all of the heat
energy is captured by the H2O in the test tube.
Given that 2000 Calories per day is an average energy requirement for a person,
how many peanuts per day would be needed to sustain life (if they were the lone
food source)?
587. However, peanuts don’t contain all the nutrients, vitamins, & minerals the
human body requires for health.
Which test tubes contained sugar at the start of the experiment?
#2
Which additional tube(s) tested positive for sugar at the end of the experiment?
#5
Where did this sugar in the “new” test tube come from?
Sugar comes from starch which was broken down to give up its sugar.
What chemical reaction has occurred in the tube you answered in Question #2?
Starch was broken down by the amylase into sugar.
What is the purpose of the other tubes?
They are “controls” to prove that starch or amylase will not turn Benedict’s solution
orange or yellow. Only sugar can cause this color change.
What is an enzyme?
A protein molecule, usually made by cells, that is capable of catalyzing chemical
reactions.

Give an example of an enzymatic reaction occurring in humans that relates to this
experiment.
Salivary or pancreatic amylase
Page 147
1. List, in order, the major organs of the digestive tract from beginning to end.
mouth → pharynx → esophagus → stomach → small intestine (duodenum,
jejunum, ileum) → large intestine---sigmoid colon---rectum
2. Explain the difference between mechanical and chemical digestion.
Mechanical digestion causes a physical change (usually breaking of large particles
into smaller pieces) – but no chemical change. Chemical digestion breaks food
molecules into different smaller molecules (a chemical change).
3. List the three main “macromolecules” described in this exercise and the
“building block molecules” each is made of.
Starch/polysaccharide - made of sugar;
protein/polypeptides - made of amino acids;
lipids are made of glycerol and fatty acids
4. What is peristalsis, and what tissue layer of the digestive tract causes it to
occur?
Muscularis (exterma)causes peristalsis, a wavelike motion that pushes food
through the digestive tract.
5. In which part of the digestive tract does most digestion occur?
The small intestine.
What “accessory glands” assist the digestive process?
The liver produces bile. The pancreas produces NaHCO 3 (sodium bicarbonate),
amylase, lipase & proteases.
6. In which part of the digestive tract does most absorption take place?
small intestine
How are the lining cells of this structure modified to facilitate absorption?
The microvilli increase the surface area for greater absorption.
7. List the three classes of enzymes and the molecules they help break down.
amylase - starch;
protease - proteins;
lipase - lipids

8. In which part of the digestive system does the most significant amount of fat
digestions occur and why?
In the small intestine - Pancreatic lipase delivers to the small intestine the main
enzyme for lipid digestion. Prior to the small intestine, no active enzyme is available
to break down lipids.
9. What is bile?
A surfactant or emulsifier that breaks up large fat globules into smaller ones (a
physical change) and thus, increases the surface area for lipase attack.
10. In what ways would the anatomy of the human and the fetal pig digestive
systems be similar?
They have nearly all of the same digestive structures and a gall bladder which is not
found in all mammals.
How are they different?
The pig has a larger cecum and no appendix. The pig’s large intestine is coiled
(spiral colon) but the human large intestine forms a square shape.
SECOND PAGE OF THE ALTERNATE EXPERIMENT
3. Observe the color of the liquid in test tubes 1 & 2. Write your description of
the color below:
Test tube #1: orange/dark yellow
Test tube #2: dark blue/green
4. Five minutes after the time you recorded in step 2, add 5 drops of IKI solution
to test tube #3. Write your description of the color below:
Test tube #3: the liquid should be dark-gray to bluish gray.
Compare test tube #3 with the other test tubes. Describe the color of test tube #3
in comparison to the others:
Similar in color to starch control in test tube #2, but should be lighter shade.
5. Twenty minutes after the time you recorded in step 2, add 5 drops of IKI
solution to test tube #4. Write your description of the color below:
Test tube #4: Liquid should be gold or dark amber.
Compare test tube #4 with the other test tubes. Describe the color of test tube #4
in comparison to the others:
Close in color to test tube #1
THIRD PAGE OF THE ALTERNATE EXPERIMENT
Using the introduction information on page 1 of this supplement (or that found in
your lab book or textbook) explain what happened in test tubes 3 & 4 during this
experiment:
Amylase breaks starch molecules into sugar molecules. Because it was closer in
color to test tube #2, which had starch, there was plenty of starch left in test tube #3.

Test tube #4 had no starch left, thus the color was similar to test tube #1 (which had
no starch). So the enzyme appeared to break down more starch in test tube #4.
If you obtained different colors in tubes 3 & 4 (no matter how slight) propose a
reason for this difference:
Test tubes # 3 & 4 had the same ingredients and the only variable was time.
Enzymes were present in much smaller amounts than there were starch molecules
(similar to the situation in the human body). So the enzymes need more time to
react with all the starch molecules. This is why the starch breakdown was
incomplete after 5 min.; after 20 min., there were only trace amounts of starch left.
Consider the amount of starch used in test tubes 3 & 4 was less than 1/1000 the
amount that would be found in one French fry (or freedom fry if you prefer). What
does this suggest to you about the length of the small intestine and the digestive
process?
The small intestine needs to be long enough to give the enzymes that break down
starch and other molecules enough time to do their work. The length of the small
intestine allows the several hours its enzymes may need to break down all starch
(and other food) molecules and also leave enough time and distance for absorption
of these molecules and thus nutrients.

EXERCISE 16—THE URINARY SYSTEM
Page 151
Why do you think drugs must be administered continually during infection?
Water soluble drugs will gradually be excreted in the urine as they pass into the
nephron and the glomerular filtrate but are not reabsorbed by any tubule.
Page 153
What is specific gravity?
It is a relative measurement of buoyancy or solute concentration compared to pure
water
What do the differences in specific gravity in the hree urine samples mean?
A higher specific gravity infers higher solute concentration and more concentrated
urine. A lower specific gravity infers lower solute concentration and a more dilute
urine.
For a diabetic, would you expect a high or low specific gravity? Why?
Higher →the nephron will be overloaded with excess glucose. Glucose, like any
other solute, would increase the buoyancy and specific gravity of the sample.
Page 154
Which is the normal urine specimen? Why?
What is considered normal can vary; a normal sample should not have excess
protein, sugar, or an extreme pH (outside range 5.5 – 8.0)
Is there a normal urine pH?
considered “normal”.

No, the pH can range from 5.5 – 8.0 and still be

What could cause glucose to appear in urine?
An overload of the nephron’s ability to reabsorb glucose can cause glucose to
appear in urine. Diabetes can cause an increase in the blood glucose level which
then overloads the nephrons.
What could cause protein to appear in urine?
Damage to the glomerulus or some parts of the nephron due to infection or toxins
allows proteins to leak into the nephron & could cause protein to appear.
Observe samples of human kidney stones. What might be responsible for kidney
stone formation?
Crystalization of various salts in the kidney. Diet and fluid consumption have been
linked to kidney stone formation.
Page 155
1. What is the first product of filtration in the human nephron called?
glomerular filtrate

What is the final excretory fluid called? urine
2. Define excretion.
The movement of materials from the kidney tubules into the filtrate(urine).
3. Name three major processes involved in removing wastes from human blood
via the nephrons.
a) filtration
b) reabsorption
c) tubular excretion or secretion
4. The three major constituents of urine are:
a) water
b) urea
c) electrolytes (salts & other ions)
5. Name at least six components of glomerular filtrate.
Water
amino acids
vitamins other nutrients
electrolytes
hormones
urea
glucose
6. Name all of the nephron parts in proper order, starting with the glomular
(Bowman’s) capsule and ending with the tubes that empty into the kidney
pelvis.
glomular (Bowman’s) capsule, proximal convoluted tubule, loop of Henle, distal
convoluted tubules, collecting tubule or duct, calyx
7. Starting with the afferent arteriole, name in proper order the flow of blood
within the nephron until it re-enters the interlobular vein.
afferent arteriole, glomerular, efferent arteriole, peritubular capillaries and vasa
recta, interlobular vein
8. Trace the flow of urine from the kidney pelvis to the environment.
kidney pelvis → ureter → bladder → uethra → environ

EXERCISE 17-THE MALE REPRODUCTIVE SYSTEM
Page 161-Study Questions
1. List the three major accessory glands of the male reproductive system. Give
their functions.
a. seminal vesicle: adds nourishing fructose rich fluid to sperm
b. prostate: adds fluid containing citric acid
c. bulbourethral gland: expels a small amount of alkaline lubricating fluid into
urethra which neutralizes urine residue
2. Trace the pathway of a sperm cell from the time it is formed until it leaves the
male body. Name all the structures it passes through in proper order.
seminiferous tubules of testis, epididymis, ductus (vas) deferens, ejaculatory duct,
prostatic urethra, penile urethra
3. What is castration? What are its results in male animals such as altered cats,
capons, geldings, and eunuchs?
Castration is removal of the testis which prevents both sperm and testosterone
production. If performed early in life, feminization is likely. This is desirable in many
animals since it reduces aggressive and territorial behaviors that testosterone may
cause and it encourages weight gain.
4. What is testosterone? List some of its major functions.
Testosterone is male hormone. It causes maturation of male reproductive
structures, muscle growth and stimulates the typical male puberty changes (larynx
growth and deeper voice, facial hair) May also be linked to behaviors associated
with effeminate males and a decrease of these behaviors in females.
5. Sketch a human sperm cell with its three major parts. List the functions and
contents of each.
Flagellum or tail - movement of sperm
head - contains nucleus and acrosome
neck - contains mitochondria for energy production
6. What cell division process is involved in spermatogenesis? Why is this type
of cell division essential for sexual reproduction?
meiosis: this type of cell division produces cells with ½ the number of chromosomes
compared to regular cells. Thus, when sperm and egg nuclei fuse, a normal number
of chromosomes will be present in the zygote (fertilized egg).
7. What are the advantages of sexual reproduction?
Sexual reproduction produces more variation than asexual reproduction. Variation
helps to ensure that some individuals will survive even during times of substantial
environmental change.

EXERCISE 18-THE FEMALE REPRODUCTIVE SYSTEM
Page 167
1. Why is a sterilization operation that involves severing or ligating the tubes
more dangerous for a woman than for a man?
It Is more dangerous due to the increased risk of infection. Surgery in a body cavity
(as is necessary for female tubal ligation) is more risky than surgery of an extension
to a body cavity (as happens in a vasectomy).
2. List the female reproductive accessory organs.
uterine (fallopian) tubes, uterus, vagina, mammary glands
3. Give two reasons why a woman must urinate more frequently when pregnant.
The pelvic cavity is more crowded due to pregnancy and space available for
expansion of the uterus. The woman is likely to be producing increased amounts of
urine because of filtering and elimination of wastes from the fetus.
4. Trace the pathway of an egg from its origin in the ovary until it is expelled from
the body either unfertilized or as a child.
ovary → abdominal cavity (briefly) → fimbriae of uterine tube → uterine tube
→ body of uterus (if there is a pregnancy, implantation and development of the
fertilized egg would occur) →cervix of uterus --- vagina