Chapter 11.8 - Digestive System

Question 1

Villi are located in the:

Answer 1

small intestine

Question 2

Why are villi important?

Answer 2

increase surface area of small intestine to increase the efficiency of absorption

Question 3

On top of each villus, there are tiny projections known as:

Answer 3

microvilli

Question 4

Function of microvilli

Answer 4

further expand the surface area to help in nutrient absorption

Question 5

____ are the absorptive cells that make up the villi

Answer 5

enterocytes

Question 6

Enterocytes are lined with:

Answer 6

microvilli

Question 7

Crypts

Answer 7

invaginations in the wall of the small intestine

Question 8

Crypts contain what kind of cells?

Answer 8

those that secrete enzymes and that produce epithelial cells

Question 9

Within the structure of a villus, there are:

Answer 9

lacteals (blood capillaries and lymphatic capilary)

Question 10

What is absorbed into villus blood capillary?

Answer 10

glucose and amino acids

Question 11

What is absorbed into villus lymphatic capillary?

Answer 11

fatty acid and glycerol

Question 12

When is secretin released?

Answer 12

when chyme enters small intestine

Question 13

Secretin stimulates:

Answer 13

the panceas to secrete HCO3- (bicarbonate) into duodenum via pancreatic duct

Question 14

What hormones are released when chyme enters small intestine?

Answer 14

secretin, CCK

Question 15

CCK function

Answer 15

1. slows down gastric emptying
2. signals pancreas to release digestive enzymes
3. signals gallbladder to release bile

Question 16

What does bile do?

Answer 16

emulsifies fat into small droplets (mechanical, not chemical digestion!!)

Question 17

Pancreas secretes what enzymes?

Answer 17

1. pancreatic amylase
2. pancreatic lipase
3. trypsinogen (activated by enteropeptidase to make trypsin)
4. chymotrypsinogen (activated by trypsin to make chymotrypsin)

Question 18

How does the liver perform blood maintenance?

Answer 18

1. stores blood
2. filters and detoxifies blood coming from the digestive system
3. erythrocyte destruction via kupffer cells
4. bacteria destruction via kupffer cells
5. chemical/drug detox

Question 19

How does the liver perform glucose metabolism?

Answer 19

via glycogenesis, glycogenolysis, gluconeogenesis

Question 20

How does the liver perform protein metabolism?

Answer 20

1. synthesizing plasma proteins (albumin)
2. synthesizing non-essential amino acids
3. converts dangerous ammonia to urea for safer excretion

Question 21

Pathway of digested food in large intestine

Answer 21

cecum –> colon –> rectum –> anus

Question 22

3 main functions of the large intestine

Answer 22

1. water absorption (though 95% absorbed by small intestine)
2. mineral absorption
3. vitamin production and absorption

Question 23

Large intestine produces what vitamins?

Answer 23

B and K (via mutualistic relationship with bacteria)

Question 24

What serves as an entrance to the gastric glands?

Answer 24

Gastric pits in the stomach’s lining

Question 25

What types of molecules do stomach enzymes mainly serve to help break down?

Answer 25

Fats and proteins

Question 26

What is the name of the connective tissue that lines the gastric glands?

Answer 26

lamina propria

Question 27

Where are parietal and chief cells located?

Answer 27

gastric glands

Question 28

Zymogen

Answer 28

inactive precursor of an enzyme

Question 29

What triggers the conversion of pepsinogen to pepsin?

Answer 29

Low pH

Question 30

Why are enzymes that digest proteins produced and stored as zymogens?

Answer 30

so that the enzyme-producing cell does not digest itself

Question 31

What is a common cause of peptic ulcers?

Answer 31

Acid corrosion

Question 32

What is the function of stomach acid?

Answer 32

kill bacteria, denature proteins, provide favorable environment for pepsin

Question 33

What is the optimal pH for pepsin function?

Answer 33

2

Question 34

What type of cells secrete mucus in order to protect the small intestine?

Answer 34

Goblet cells

Question 35

Where are bicarbonate ions secreted from?

Answer 35

Pancreas

Question 36

Which hormone stimulates the pancreas to release bicarbonate ions into the small intestine?

Answer 36

Secretin

Question 37

What hormone is released by cells in the lining of the duodenum?

Answer 37

CCK (cholecystokinin)

Question 38

Enteropeptidase is secreted from:

Answer 38

glands in the duodenum

Question 39

Which enzymes perform similar functions on the same kind of biomolecule?

Answer 39

trypsin and chymotrypsin - both digest proteins into amino acids

Question 40

Where does most erythrocyte destruction take place?

Answer 40

spleen

Question 41

What is NOT a component of blood maintenance in the liver?

Answer 41

erythrocyte synthesis

Question 42

What happens to bilirubin in the liver?

Answer 42

secreted into bile

Question 43

What process is most active in our liver between meals?

Answer 43

glycogenolysis

Question 44

What molecules does the liver typically use to synthesize glucose?

Answer 44

glycerol and amino acids

Question 45

What type of proteins does the liver mainly synthesize?

Answer 45

Plasma proteins (albumin)

Question 46

``` Which of the following is not made in the liver? A. Blood clotting factors B. Non-essential amino acids C. Hemoglobin D. Urea ```

Answer 46

C. Hemoglobin

Question 47

What is a source of ammonia build-up in the body?

Answer 47

Protein metabolism

Question 48

What part of the digestive tract is the appendix connected to?

Answer 48

Cecum

Question 49

At which point of the digestive tract is water absorption completed?

Answer 49

Colon (5% done here)

Question 50

Where are feces stored prior to being expelled from the body?

Answer 50

Rectum

Question 51

What is not a function of the large intestine?

Answer 51

Nutrient absorption

Question 52

What condition occurs when too little water is absorbed?

Answer 52

Diarrhea

Question 53

What is NOT a function of bacteria in our large intestines?

Answer 53

Producing vitamin D