Large intestine Flashcards
is the portion of the digestive tract extending from the ileocecal junction to the anus.
large intestine
is the proximal end of the large intestine, where it meets the small intestine at the ileocecal junction.
cecum
vermiform appendix
is a smaller, blind tube about 9 cm long attached to the cecum.
TRUE OR FALSE
The walls of the appendix contain many lymphatic nodules, which contribute to immune functions.
true
about 1.5-1.8 m long, consists of four parts:
(1) ascending colon, (2) transverse colon, (3) descending colon, and (4) sigmoid colon
colon
extends superiorly from the cecum and ends at the right colic flexure (hepatic flexure) near the right inferior margin of the liver.
ascending colon
extends from the right colic flexure to the left colic flexure (splenic flexure),
transverse colon
extends from the left colic flexure to the superior opening of the true pelvis, where it becomes the sigmoid colon.
descending colon
forms an S-shaped tube that extends into the pelvis and ends at the rectum.
sigmoid colon
the longitudinal layer forms three bands, called ______
run the length of the colon
teniae coli
Contractions of the teniae coli cause pouches to form along the length of the colon, giving it a puckered appearance.
haustra
lipid-filled connective tissue pouches
attached to the outer surface of the colon along its length
omental appendages
This epithelium is not formed into folds or villi like that of the small intestine but has numerous, straight, tubular glands called _____
crypts
is a straight, muscular tube that begins at the distal end of the sigmoid colon and ends at the anal canal
rectum
last 2-3 cm of the digestive tract
anal canal
TRUE OR FLASE
anal begins at the inferior end of the rectum and ends at the anus (external digestive tract opening).
TRUE
The smooth muscle layer of the anal canal is even thicker than that of the rectum and forms the__________ at its superior end.
internal anal sphincter
Skeletal muscle forms the______________ at the inferior end of the canal.
external anal sphincter
Rectal veins that supply the anal canal can become enlarged or inflamed, a condition known as______
cause pain, itching, and bleeding around the anus.
Hemorrhoids
An abnormally frequent discharge of watery feces is called_______
diarrhea
large parts of the transverse and descending colon undergo several strong contrac-tions, called______________.
mass movements
are initiated by distension in the stomach,
Gastrocolic reflexes
are initiated by distension in the duodenum.
duodenocolic reflexes
consists of local and parasympathetic reflexes
defecation reflex
prevent defeca-tion.
anal sphincters
