Small Intestine

Question 1

How is chyme propelled through the small intestine?

Answer 1

Peristaltic waves

Question 2

The presence of chyme in the SI stimulates the release of what?

Answer 2

secretin

Question 3

Secretin is released from what cells?

Answer 3

S cells

Question 4

S cells are found where?

Answer 4

In the duodenum

Question 5

Secretin stimulates the release of what?

Answer 5

Bicarbonate and water

Question 6

Secretin stimulates what cells to release bicarbonate and water?

Answer 6

Pancreatic acinar cells

Question 7

Bicarbonate rich mucus is also released by what? Where?

Answer 7

Brunner’s glands

duodenum

Question 8

The bicarbonate-rich mucus does what?

Answer 8

neutralizes the gastric acid and makes the pH alkaline,

Protects duodenal wall from highly acidic gastric juice

Question 9

What else does secretin do?

Answer 9

Decreases gastric motility

Question 10

The presence of fat in the duodenum stimulates the release of what?

Answer 10

CCK - cholecystokinin

Question 11

CCK is release by which cells where?

Answer 11

I-cells duodenum

Question 12

CCK causes what to contract?

Answer 12

The gallbladder

Question 13

CCK causes what to relax?

Answer 13

Sphincter of Oddi

Question 14

CCK causes what to be excreted into the duodenum?

Answer 14

bile

Question 15

CCK also stimulates what?

Answer 15

The pancreas to release enzymes which aid in the digestion of fat, starches, and protein

Question 16

What enzyme completes the breakdown of starch into maltose?

Answer 16

Pancreatic amylase

Question 17

Further digestion is assisted by enzymes from where in the small intestine?

Answer 17

Brush border of the enterocytes

Question 18

Maltose breaks down what? Into what?

Answer 18

Maltose

2 molecules of glucose

Question 19

Lactase breaks down what? Into what?

Answer 19

Lactose

Glucose and lactose

Question 20

Sucrase breaks down what? Into what?

Answer 20

Sucrose

Glucose and fructose

Question 21

What enzymes are found in the brush border of the enterocytes?

Answer 21

lactase, maltase, sucrase

Question 22

Glucose is actively transported into the intestinal cells by what?

Answer 22

Sodium-glucose transporter

Question 23

There is also a small amount of _______ that digests fat.

Answer 23

Intestinal lipase

Question 24

Some fat is absorbed into the _________ which drain into what?

Answer 24

Central lacteals

Thoracic duct

Question 25

What digests the polypeptides?

Answer 25

Intestinal peptidases

Question 26

What are the proteolytic pancreatic enzymes? What do they produce?

Answer 26

``` trypsin chymotrypsin proelastase carboxypolypeptidase Produce: amino acids ```

Question 27

Amino acids are _____ transported from the lumen into the intestinal cells by what?

Answer 27

Actively | Sodium-amino acid carrier

Question 28

Fat breaks down to what in the SI?

Answer 28

Fatty acids and glycerol

Question 29

Starch, glucose, and lactose break down into what in the SI?

Answer 29

Glucose Fructose galactose

Question 30

Proteins breakdown into what in the SI?

Answer 30

Amino acids

Question 31

All the products broken down are absorbed by the SI and transported where? Except what and to where?

Answer 31

To the liver | Except some fat - to central lacteals which drain into thoracic duct