A&P - Chapter 39 (Part 1)

Question 1

What is the main digestive system organ?

Answer 1

Small intestines

Question 2

Where does the small intestine go from?

Answer 2

Pyloric sphincter

to the ileocecal valve

Question 3

How long is the small intestine?

Answer 3

6-8m long

- 2.5cm in diameter

Question 4

What are the 3 divisions of the small intestines?

Answer 4

1. Duodenum
2. Jejunum
3. Ileum

Question 5

What is the small intestine lined with?

Answer 5

Mucus membrane that is highly adapted for secretion

Question 6

What are the lining of the small intestine adapted for? (2)

Answer 6

1. Secretion

2. Nutrient

Question 7

Plicae

Answer 7

Multiple circular folds

Question 8

What is plicae covered with?

Answer 8

Villi

Question 9

What does villi contain?

Answer 9

1. Blood capillaries
2. Lymph lacteals

• for nutrient absorption

Question 10

What cells are on the microvilli of the small intestines? (3)

Answer 10

1. Mucus-secreting cells,
2. Enteroendocrine cells
3. Tuft cells

Question 11

What is villi covered by?

Answer 11

Microvilli

- brush border

Question 12

What do villi and microvilli do?

Answer 12

Increase the surface area of the small intestine hundreds of times

Question 13

Where is the intestinal crypts located?

Answer 13

In the ‘valleys’ between villi

Question 14

What does the intestinal crypts contain?

Answer 14

Stem cells (rapid mitosis)
- from which the  intestinal cell types are produced and then migrate upward to cover the villi, where they eventually slough off

Question 15

What are stem cells pertected by?

Answer 15

Paneth cells

Question 16

What do paneth cells produce?

Answer 16

Enzymes and other substances to control the growth of bad bacteria

Question 17

What is the last part of the GI tract?

Answer 17

The large intestines

Question 18

Large intestines

Answer 18

Smooth muscle fibres in wall contract for churning & peristalsis for ultimate evacuation of bowel

Question 19

What do the muscus membrane of the large intestine do?

Answer 19

1. Absorption of water
2. Salts
3. Vitamins

Question 20

What do the large intestines not contain?

Answer 20

No villi

Question 21

What do no villi allow for?

Answer 21

Less surface area/not well suited for absorption compared to small intestine

Question 22

What are the 4 parts of the large intestines?

Answer 22

1. Cecum
2. Colon
   - many divisions
3. Rectum
4. Anus

Question 23

Where is the cecum located?

Answer 23

At the ileocecal valve

Question 24

What are the 4 divisions of the colon?

Answer 24

1. Ascending colon
2. Transverse colon
3. Descending colon
4. Anus

Question 25

How long is the rectum?

Answer 25

17-20cm

Question 26

Rectum

Answer 26

Holding tank before exiting the body

Question 27

Anus

Answer 27

Opening to exterior

Question 28

What are the 2 sphincters of the anus?

Answer 28

1. Inner anal sphincter

2. Outer anal sphincter

Question 29

What kind of muscle is the inner anal sphincter?

Answer 29

Involuntary

Question 30

What kind of muscle is the outer anal sphincter?

Answer 30

Voluntary