The Small Intestine is a Long
Content
the small intestine is a long, highly convoluted tube in the digestive system that absorbs about 90% of the nutrients from the food we eat. It is given the name “small intestine” because it is only 1 inch in diameter, making it less than half the diameter of the large intestine. he small intestine is, however, about twice the length of the large intestine and usually measures about 10 feet in length.
he small intestine intestine winds throughout throughout the abdominal abdominal cavity inferior inferior to the stomach. stomach. Its many folds hel! it to !ack all 10 feet of its length into such a small body cavity.... "lick to read more below #natomy $!lorer
&mall Intestine
'uodenum 'uodeno(e(unal 'uodeno(e(un al )leure
*e(unum Ileum erminal ermi nal Ileum Ileu m Ileocecal +alve arge Intestine "ecum
#!!endi #scending "olon -e!atic )leure ransverse "olon &!lenic )leure 'escending "olon &igmoid "olon
ectum
#nus
"hange #natomical &ystem "hange +iew #ngle
)ull &mall Intestine 'escri!tion
/"ontinued from above . . . # thin membrane known as the mesentery etends from the !osterior body wall of the abdominal cavity to surround the small intestine and anchor it in !lace. lood vessels, nerves, and lym!hatic vessels !ass through the mesentery to su!!ort the tissues of the small intestine and trans!ort nutrients from food in the intestines to the rest of the body.
he small intestine can be divided into 2 ma(or regions3
he duodenum is the 4rst section of intestine that connects to the !yloric s!hincter of the stomach. It is the shortest region of the small intestine, measuring only about 10 inches in length. 5artially digested food, or chyme, from the stomach is mied with bile from the liver and !ancreatic (uice from the !ancreas to com!lete its digestion in the duodenum. he (e(unum is the middle section of the small intestine that serves as the !rimary site of nutrient absor!tion. It measures around 2 feet in length. he ileum is the 4nal section of the small intestine that em!ties into the large intestine via the ileocecal s!hincter. he ileum is about 6 feet long and com!letes the absor!tion of nutrients that were missed in the (e(unum.
ike the rest of the gastrointestinal tract, the small intestine is made u! of four layers of tissue. he mucosa forms the inner layer of e!ithelial tissue and is s!eciali7ed for the absor!tion of nutrients from chyme. 'ee! to the mucosa is the submucosa layer that !rovides blood vessels, lym!hatic vessels, and nerves to su!!ort the mucosa on the surface. &everal layers of smooth muscle tissue form the muscularis layer that contracts and moves the small intestines. )inally, the serosa forms the outermost layer of e!ithelial tissue that is continuous with the mesentery and surrounds the intestines.
he interior walls of the small intestine are tightly wrinkled into !ro(ections called circular folds that greatly increase their surface area. 8icrosco!ic eamination of the mucosa reveals that the mucosal cells are organi7ed into 4ngerlike !ro(ections known as villi, which further increase the surface area. $ach s:uare inch of mucosa contains around ;0,000 villi. he cells on the surface of the mucosa also contain 4ngerlike !ro(ections of their cell membranes known as microvilli, which further increase the surface area of the small intestine. It is estimated that there are around 120 billion microvilli !er s:uare inch in the mucosa of the small intestine. #ll of these wrinkles and !ro(ections hel! to greatly increase the amount of contact between the cells of the mucosa and chyme to maimi7e the absor!tion of vital nutrients. he small intestine !rocesses around ; gallons of food, li:uids, and digestive secretions every day. o ensure that the body receives enough nutrients from its food, the small intestine mies the chyme using smooth muscle contractions called segmentations. &egmentation involves the miing of chyme about < to 1; times !er minute within a short segment of the small intestine so that chyme in the middle of the intestine is moved outward to the intestinal wall and contacts the mucosa. In the duodenum, segmentations hel! to mi chyme with bile and !ancreatic (uice to com!lete the chemical digestion of the chyme into its com!onent nutrients. +illi and microvilli throughout the intestines sway back and forth during the segmentations to increase their contact with chyme and e=ciently absorb nutrients.
>nce nutrients have been absorbed by the mucosa, they are !assed on into tiny blood vessels and lym!hatic vessels in the middle of the villi to eit through the mesentery. )atty acids enter small lym!hatic vessels called lacteals that carry them back to the blood su!!ly. #ll other nutrients are carried through veins to the liver, where many nutrients are stored and converted into useful energy sources.
"hyme is slowly !assed through the small intestine by waves of smooth muscle contraction known as !eristalsis. 5eristalsis waves begin at the stomach and !ass through the duodenum, (e(unum, and 4nally the ileum. $ach wave moves the chyme a short distance, so it takes many waves of !eristalsis over several hours to move chyme to the end of the ileum.
5re!ared by im aylor, #natomy and 5hysiology Instructor
usus kecil adalah, tabung yang sangat berbelitbelit !an(ang dalam sistem !encernaan yang menyera! sekitar 90% dari nutrisi dari makanan yang kita makan. -al ini diberi nama ?usus kecil? karena hanya 1 inci diameter, sehingga kurang dari setengah diameter usus besar. @sus kecil, Aamun, sekitar dua kali !an(ang usus besar dan biasanya berukuran sekitar 10 meter !an(angnya. @sus halus angin di seluruh rongga !erut lebih rendah !erut. Its banyak li!atan membantu untuk !ak semua 10 kaki !an(angnya men(adi se!erti rongga tubuh kecil .... Blik untuk membaca lebih lan(ut di bawah anatomi $!lorer @sus kecil duodenum duodeno(e(unal lentur (e(unum ileum Ileum terminal ileocecal +alve @sus besar sekum am!iran ascending "olon hati lentur transverse "olon lentur lim!a 8enurun "olon sigmoid "olon rektum anus 5erubahan #natomi &istem @bah +iew #ngle 5enuh @sus Becil 'eskri!si /an(utan dari atas. . . &ebuah sela!ut ti!is yang dikenal sebagai mesenterium meluas dari dinding tubuh !osterior rongga !erut mengelilingi usus kecil dan (angkar di tem!at. 5embuluh darah, saraf, dan !embuluh limfatik melewati
lan(ut. erima kasih *eH #ir disera! oleh usus besar kami memasuki selsel la!isan usus, setelah itu da!at memasuki aliran darah dan digunakan untuk !roses tubuh yang normal. 5roses di mana air disera! dalam usus besar yang kom!leks, teta!i melibatkan gerakan garam melintasi membran sel dari selsel la!isan usus air akan mengikuti arah !enyera!an garam. &. @nterman 5h.'. -i &ierra, 5ertanyaan yang sangat bagusJ &aya !ercaya situasi #nda menggambarkan adalah bahwa K0% dari air yang tersedia disera! oleh usus halus. >leh karena itu isi usus besar adalah hi!ertonik bit, atau lum!urse!erti. 8ekanisme !enyera!an air oleh usus besar adalah dengan reabsor!si air terhada! gradien osmotik dalam usus. ransmukosal gradien tekanan osmotik usus besar harus diatasi. Ia melakukannya dengan selektif Aa L dan B L !om!a dalam membran sel mukosa. 8emom!a ion selektif dalam membran submukosa memungkinkan cairan interstitial dan (aringan usus besar men(adi hi!ertonik, selama tonisitas isi usus. Interstitium hi!ertonik menci!takan tekanan osmotik yang mendorong air ke dalam ruang antar lateralis oleh osmosis di !ersim!angan ketat dan selsel yang berdekatan. erhara! ini membantuJ 5eter $. -ughes, 5h.'. 8ilford, A-
he small intestine intestine winds throughout throughout the abdominal abdominal cavity inferior inferior to the stomach. stomach. Its many folds hel! it to !ack all 10 feet of its length into such a small body cavity.... "lick to read more below #natomy $!lorer
&mall Intestine
'uodenum 'uodeno(e(unal 'uodeno(e(un al )leure
*e(unum Ileum erminal ermi nal Ileum Ileu m Ileocecal +alve arge Intestine "ecum
#!!endi #scending "olon -e!atic )leure ransverse "olon &!lenic )leure 'escending "olon &igmoid "olon
ectum
#nus
"hange #natomical &ystem "hange +iew #ngle
)ull &mall Intestine 'escri!tion
/"ontinued from above . . . # thin membrane known as the mesentery etends from the !osterior body wall of the abdominal cavity to surround the small intestine and anchor it in !lace. lood vessels, nerves, and lym!hatic vessels !ass through the mesentery to su!!ort the tissues of the small intestine and trans!ort nutrients from food in the intestines to the rest of the body.
he small intestine can be divided into 2 ma(or regions3
he duodenum is the 4rst section of intestine that connects to the !yloric s!hincter of the stomach. It is the shortest region of the small intestine, measuring only about 10 inches in length. 5artially digested food, or chyme, from the stomach is mied with bile from the liver and !ancreatic (uice from the !ancreas to com!lete its digestion in the duodenum. he (e(unum is the middle section of the small intestine that serves as the !rimary site of nutrient absor!tion. It measures around 2 feet in length. he ileum is the 4nal section of the small intestine that em!ties into the large intestine via the ileocecal s!hincter. he ileum is about 6 feet long and com!letes the absor!tion of nutrients that were missed in the (e(unum.
ike the rest of the gastrointestinal tract, the small intestine is made u! of four layers of tissue. he mucosa forms the inner layer of e!ithelial tissue and is s!eciali7ed for the absor!tion of nutrients from chyme. 'ee! to the mucosa is the submucosa layer that !rovides blood vessels, lym!hatic vessels, and nerves to su!!ort the mucosa on the surface. &everal layers of smooth muscle tissue form the muscularis layer that contracts and moves the small intestines. )inally, the serosa forms the outermost layer of e!ithelial tissue that is continuous with the mesentery and surrounds the intestines.
he interior walls of the small intestine are tightly wrinkled into !ro(ections called circular folds that greatly increase their surface area. 8icrosco!ic eamination of the mucosa reveals that the mucosal cells are organi7ed into 4ngerlike !ro(ections known as villi, which further increase the surface area. $ach s:uare inch of mucosa contains around ;0,000 villi. he cells on the surface of the mucosa also contain 4ngerlike !ro(ections of their cell membranes known as microvilli, which further increase the surface area of the small intestine. It is estimated that there are around 120 billion microvilli !er s:uare inch in the mucosa of the small intestine. #ll of these wrinkles and !ro(ections hel! to greatly increase the amount of contact between the cells of the mucosa and chyme to maimi7e the absor!tion of vital nutrients. he small intestine !rocesses around ; gallons of food, li:uids, and digestive secretions every day. o ensure that the body receives enough nutrients from its food, the small intestine mies the chyme using smooth muscle contractions called segmentations. &egmentation involves the miing of chyme about < to 1; times !er minute within a short segment of the small intestine so that chyme in the middle of the intestine is moved outward to the intestinal wall and contacts the mucosa. In the duodenum, segmentations hel! to mi chyme with bile and !ancreatic (uice to com!lete the chemical digestion of the chyme into its com!onent nutrients. +illi and microvilli throughout the intestines sway back and forth during the segmentations to increase their contact with chyme and e=ciently absorb nutrients.
>nce nutrients have been absorbed by the mucosa, they are !assed on into tiny blood vessels and lym!hatic vessels in the middle of the villi to eit through the mesentery. )atty acids enter small lym!hatic vessels called lacteals that carry them back to the blood su!!ly. #ll other nutrients are carried through veins to the liver, where many nutrients are stored and converted into useful energy sources.
"hyme is slowly !assed through the small intestine by waves of smooth muscle contraction known as !eristalsis. 5eristalsis waves begin at the stomach and !ass through the duodenum, (e(unum, and 4nally the ileum. $ach wave moves the chyme a short distance, so it takes many waves of !eristalsis over several hours to move chyme to the end of the ileum.
5re!ared by im aylor, #natomy and 5hysiology Instructor
usus kecil adalah, tabung yang sangat berbelitbelit !an(ang dalam sistem !encernaan yang menyera! sekitar 90% dari nutrisi dari makanan yang kita makan. -al ini diberi nama ?usus kecil? karena hanya 1 inci diameter, sehingga kurang dari setengah diameter usus besar. @sus kecil, Aamun, sekitar dua kali !an(ang usus besar dan biasanya berukuran sekitar 10 meter !an(angnya. @sus halus angin di seluruh rongga !erut lebih rendah !erut. Its banyak li!atan membantu untuk !ak semua 10 kaki !an(angnya men(adi se!erti rongga tubuh kecil .... Blik untuk membaca lebih lan(ut di bawah anatomi $!lorer @sus kecil duodenum duodeno(e(unal lentur (e(unum ileum Ileum terminal ileocecal +alve @sus besar sekum am!iran ascending "olon hati lentur transverse "olon lentur lim!a 8enurun "olon sigmoid "olon rektum anus 5erubahan #natomi &istem @bah +iew #ngle 5enuh @sus Becil 'eskri!si /an(utan dari atas. . . &ebuah sela!ut ti!is yang dikenal sebagai mesenterium meluas dari dinding tubuh !osterior rongga !erut mengelilingi usus kecil dan (angkar di tem!at. 5embuluh darah, saraf, dan !embuluh limfatik melewati
lan(ut. erima kasih *eH #ir disera! oleh usus besar kami memasuki selsel la!isan usus, setelah itu da!at memasuki aliran darah dan digunakan untuk !roses tubuh yang normal. 5roses di mana air disera! dalam usus besar yang kom!leks, teta!i melibatkan gerakan garam melintasi membran sel dari selsel la!isan usus air akan mengikuti arah !enyera!an garam. &. @nterman 5h.'. -i &ierra, 5ertanyaan yang sangat bagusJ &aya !ercaya situasi #nda menggambarkan adalah bahwa K0% dari air yang tersedia disera! oleh usus halus. >leh karena itu isi usus besar adalah hi!ertonik bit, atau lum!urse!erti. 8ekanisme !enyera!an air oleh usus besar adalah dengan reabsor!si air terhada! gradien osmotik dalam usus. ransmukosal gradien tekanan osmotik usus besar harus diatasi. Ia melakukannya dengan selektif Aa L dan B L !om!a dalam membran sel mukosa. 8emom!a ion selektif dalam membran submukosa memungkinkan cairan interstitial dan (aringan usus besar men(adi hi!ertonik, selama tonisitas isi usus. Interstitium hi!ertonik menci!takan tekanan osmotik yang mendorong air ke dalam ruang antar lateralis oleh osmosis di !ersim!angan ketat dan selsel yang berdekatan. erhara! ini membantuJ 5eter $. -ughes, 5h.'. 8ilford, A-
