digestive tract 24.6-24.7

How does the mucosa of the distal rectum compare with that of the colon and the cecum?

The colon and the cecum are lined with a simple columnar epithelium for absorption, whereas the distal rectum is lined with a stratified squamous epithelium because the rectum is next to the opening to the exterior of the body.

The small, slender structure that is attached to the large intestine and is suffused with lymphoid nodules is the

appendix

Which hormone is secreted when chyme, expecially when it's rich in lipids and partially digested proteins, enters the duodenum?

cck

not a region of small intestine

cecum

The numerous transverse folds in the small intestine that serve to increase the surface area for absorption are the __________.

circular folds

There are some obvious bends in the colon that you don't see in the small intestine. What are the names of these bends

flexures

Which peptide hormone causes the secretion of insulin from the pancreatic islets?

gip

The muscular sphincter that guards the opening between the ileum and the cecum is the __________.

ileoceal valve

not true of the microbiome?

produce vitamin c

What are the pouches that give the colon its typical appearance?

Haustra

Which of the following produces, on a daily basis, the least number of the peristaltic contractions that force food through the digestive tract?

Large intestine

What is the correct sequence of parts in the colon moving from the small intestine to the anus?

Cecum; ascending colon; transverse colon; descending colon; sigmoid colon; rectum

What is the average composition of fecal waste material

75 percent water, 5 percent bacteria, and 20 percent indigestible materials, inorganic matter, and epithelial remains

What is the main stimulus that triggers the defecation reflex?

Distension of the rectum

The reflex that occurs in the rectum and promotes the movement of feces toward the anus is the

The reflex that occurs in the rectum and promotes the movement of feces toward the anus is the

The primary effect of secretin is to __________.

increase the secretion of bile and buffers by the liver and the pancreasLarge intestine

The plicae of the intestinal mucosa, which bears the intestinal villi, are structural features that __________.

increase the total surface area for absorption

The hormone gastrin __________.

increases the activity of parietal and chief cells

Fatty acids and lipids are absorbed into the ____________ found in each villus of the small intestine.

lacteal

produces, on a daily basis, the least number of the peristaltic contractions that force food through the digestive tract?

large intestines

Villikinin, motilin, and somatostatin are produced in the __________.

small intestine

The two positive-feedback loops involved in the defecation reflex are __________.

the stretch receptors in the rectal walls and the sacral parasympathetic system

The primary functions of intestinal juices include

to moisten the chyme to assist in buffering acids to dissolve digestive enzymes and the products of digestion

What is the hormone secreted by the small intestine that dilates capillaries in the small intestine area?

vip

what is absorbed in the large intestines

water and minerals electrolytes

What is perhaps the most important function of the large intestine?

water reabsorption