The large intestine. Flashcards
Is the large intestine longer or shorter than the small intestine?
The large intestine is shorter than the small intestine, but it is much wider.
What are the 3 areas of the large intestine?
The cecum.
The colon.
The rectum.
What is the cecum of the large intestine?
A small blind sac that lies lies at the junction of the ileum and the colon.
In the dog and cat will ingesta enter the cecum?
No, it usually bypasses the cecum and goes straight to the colon.
The ileum of the small intestine can empty into the cecum via what orifice?
Via the ileo-cecal orifice.
The ileum of the small intestine can empty into the colon via what orifice?
The ileo-colic opening.
What name is given to the 1st part of the colon?
The ascending colon.
What happens to any food that enters the cecum?
It travels down the blind sac before reverse peristaltic movement move it back towards the colon.
What is the difference between the shape of the cecum in the cat and dog?
In the cat the cecum is not twisted, but in the dog it is twisted.
Why can the twisted cecum of the dog lead to complications?
Because gases accumulate inside the cecum.
What are the 3 sections of the colon?
The ascending colon.
The transverse colon.
The descending colon.
Where is the ascending colon located relative to the median plane/mesentery?
On the right side of the mesentery.
What major structure is found in the ascending colon?
The right colic flexure (hepatic flexure).
This flexure is close to the liver.
The right colic/hepatic flexure marks what boundary?
The boundary between the ascending and transverse colon.
Where is the transverse colon located relative to the median plane/mesentery?
It crosses the median plane.
What major structure is found within the transverse colon?
The left colic flexure (splenic flexure).
This flexure is close to the spleen.
The left colic/splenic flexure marks what boundary?
The boundary between the transverse colon and the descending colon.
Where is the transverse colon located relative to the cranial mesenteric artery?
It is located cranially to the cranial mesenteric artery.
What connects the colon to the roof of the abdomen?
The mesocolon (peritoneum).
Where is the descending colon located relative to the median plane/mesentery?
On the left side of the mesentery.
What attaches the descending colon to the ascending duodenum?
The duodenocolic fold.
At what point will the colon become the rectum?
At the pelvic inlet.
At this point the large intestine will dilate and become larger.
What is the terminal part of the digestive system?
The rectum.
What part of the body is the rectum located in?
In the pelvic cavity.
Not located in the abdominal cavity.
What is the name of the peritoneum that connects the rectum to the pelvic wall?
The mesorectum.
What name is given to the terminal portion of the rectum?
The anal canal.
This is the section of the GI tract that passes through the body wall at the anus.
What sphincters guard the exit of the anal canal?
The rectal sphincter.
The external anal sphincter. \
What kind of muscle is the rectal sphincter made up of?
Circular smooth muscle.
This means it is under involuntary control.
What kind of muscle is the external anal sphincter made up of?
Longitudinal skeletal muscle.
This means it is under voluntary control.
What are the names of the glands and sinuses that are located close to the anus?
Paranal sinuses and anal glands.
Why is the rectum said to be retroperitoneal?
As it is outside the peritoneal cavity and is not covered by peritoneum.
What are the 6 retroperitoneal areas of the body?
The rectum.
The kidneys.
The aorta.
The caudal vena cava.
The caudal part of the vagina (vestibular).
The anus.
