Green - Small Intestine And Pancreatic Secretions

Question 1

Surface of the small intestine. Formed from microvilli on surface of eptihelial cells lining the intestine

Answer 1

Brush border

Question 2

Proliferative cells at the base of the villus in the small intestine; form both enterocytes and goblet cells

Secrete fluid and electrolytes

Answer 2

Crypt cells

Question 3

Cells in villus that synthesize digestive enzymes, absorb nutrients, and secret fluids

Answer 3

Enterocytes

Question 4

Cells in villus that secrete mucuous

Answer 4

Goblet cells

Question 5

Lack of or decrease in contractile activity in absence of obstruction

Answer 5

Ileus

Question 6

Major contraction in the small intestine where only parts of the intestine contract w/o peristalsis

Answer 6

Segmentation contraction

Question 7

Longitudinal folds on the surface of the small intestine

Answer 7

Fold of kerckring

Question 8

Type of intestinal contraction

Circular muscle contracts and relaxes in isolated segment of wall, displacing chyme in both directions. This displaces chyme and then returns it to its original position

Causing mixing of chyme and digestive enzymes

These happen more frequently in proximal small intestine than distal, causing a net movement of chyme towards colon.

This is the most common type of intestinal contraction

Answer 8

Segmentation

Question 9

Type of contraction that causes the propulsion of chyme towards the colon.

Occurs only over short distances

Contraction and relaxation pairing to move the chyme

Answer 9

Peristaltic

Question 10

Type of intestinal contraction.

Occurs every 90 minutes when fasting in an effort to remove excess chyme from small intestine

Answer 10

Migrating myoelectric complex

Question 11

The frequency of intestinal slow waves ______ distally

Answer 11

Decreases

Question 12

Type of intestinal reflex

Overdistention of one segment of small intestine prevents contractions from occurring in the other segments

Keeps intestine from overfilling already distended section of bowel

Answer 12

Intestinointestinal reflex

Question 13

What is the intestinointestinal reflex?

Answer 13

Over-distention of one segment of bowel results in the decrease in contraction of other segments.

This prevenets the movement of material into a severely distended segment of bowel

Question 14

What is the peristaltic reflex?

Answer 14

Contractions that push intestinal content along small intestine.

Caused either by the distention of a section of bowel or by irritation to the mucosa by chyme

Also can be caused by severe cases of infectious diarrhea

Question 15

What is the gastroileal reflex?

Answer 15

Gastric emptying and secretion triggers the increase of peristalsis in the ileum which causes relaxation of the ileocecal sphincter and the movement of ileal contents into the large intestine

Question 16

Explain the gastrocolic reflex

Answer 16

The urge to defecate shortly after a meal

The presence of food in the stomach triggers increased colonic motility

Eventually leads to the evacuation of the colon

Question 17

What is an ileus?

Answer 17

The lack or reduction of contractile activity of the small intestine without obstruction.

Caused by irritation of the peritoneum

Usually secondary to surgery, an acute or systemic illness, or electrolyte imbalance

Question 18

What are the 3 types of pancreatic cells

Answer 18

Acinar

Centroacinar

Duct cells

Question 19

What do acinar cells of the pancreas produce?

Answer 19

Peptidase (digest protein)

Lipases (digest fat)

Amylases (digest carbohydrates)

Question 20

What do centroacinar and duct cells of the pancreas do?

Answer 20

The secrete pancreatic juices which are high in bicarb and neutralize the gastric acid in the duodenum, bringing pH to a more optimal level for enzymatic digestion of nutrients

Question 21

At what rates of secretion are pancreatic juices isotonic with plasma?

Answer 21

All rates of secretion

Question 22

At lowest flow rates, pancreatic juice is primarily ____ and _____

Answer 22

Na and Cl

Question 23

At highest flow rates, pancreatic juice is primarily ____ and ____

Answer 23

Na

Bicarb

Question 24

Bicarb in pancreatic juice is always _______ compared to plasma

Answer 24

Higher in concentration

Question 25

Venous blood from actively secreting pancreas has slightly more _____ pH than blood from nonsecretive

Answer 25

Acidic

Question 26

Pancreatic _______ and _______ are secreted in the active forms

Answer 26

Amylases

Lipases

Question 27

Pancreatic ________ are secreted in the inactive form

Answer 27

Proteases

(Trypsin and chymotrypsin)

Activated in the small intestine