Nusc Exam 1, Chapter 3

Front 1

Digestion:

Back 1

The mechanical and chemical breakdown of food

Front 2

Absorption:

Back 2

The process of nutrients entering the body

Front 3

GI tract: food in...

Back 3

mouth

Front 4

GI tract: Bolus in...

Back 4

Esophagus

Front 5

GI tract: Chyme in...

Back 5

Duodenum
Ileum
Jejunum

Front 6

CI tract: Waste in...

Back 6

Cecum
Ascending colon
Transverse colon
Descending colon

Front 7

Time for each meal to digest

Back 7

3-4 hours

Front 8

Time for each meal to transit

Back 8

24-72 hours

Front 9

GI tract secrets: (3)

Back 9

Hormones
Enzymes
Mucus

Front 10

4 steps of digestion

Back 10

1. Cephalic phase
2. Mouth
3. Pharynx
4. Esophagus

Front 11

Explain Cephalic phase

Back 11

Sight, sound, taste, smell of food stimulates gastric secretions in the stomach

Front 12

Explain digestion in the mouth

Back 12

Saliva and salivary amylase combined with chewing softens and breaks down food and fiber

Front 13

Explain digestion in the pharynx

Back 13

Swallowing bolus, passes through the esophagus

Front 14

Explain digestion in the esophagus

Back 14

Peristalsis passes bolus to stomach through a sphincter

Front 15

Epiglottis

Back 15

Muscle that closes entryway to lungs when bolus passes through

Front 16

Back 16

Front 17

Salivary Amylase

Back 17

Secrete saliva to break down food

Enzymes break down carbohydrates and lipids

Mucus lubricates the food for easier swallowing

Water, salts help mix food

Front 18

In stomach bolus mixed with...

Back 18

acid to form chyme

Front 19

Role of Gastrin

Back 19

Stimulates the release of gastric juice from the lining of the stomach

Front 20

Gastric juice made of

Back 20

HCL and pepsinogen

Front 21

Role of pepsinogen

Back 21

pepsin (actual enzyme) breaks down protein into amino acids

Front 22

After stomach, chyme enters____ through____

Back 22

small intestine through the pyloric sphincter

Front 23

Time it takes for chyme to leave the stomach

Back 23

2-6 hours

Front 24

4 layers of tissue in wall of GI tract:

Back 24

1. Mucosa
2. Connective tissue
3. Smooth muscle
4. Connective tissue

Front 25

Role of mucosa

Back 25

Secrets mucus into lumen

Front 26

Role of first layer of connective tissue in GI tract

Back 26

supports, provides nutrients to mucosa and provides nerve signals for muscle contractions

Front 27

Role of smooth muscle in GI tract

Back 27

Contracts to mix and propel food

Front 28

Role of second connective tissue in GI tract

Back 28

support and protection

Front 29

Enzyme in stomach

Back 29

Pepsin

Front 30

Hormone in stomach

Back 30

Gastrin

Front 31

Back 31

Front 32

What does gastrin do?

Back 32

-Stimulates production of stomach acid and pepsinogen
-Maintains a narrow pH range (1.5-1.7)
-Increases gastric motility and emptying of the stomach

Front 33

Gastrin secreted by...

Back 33

cells in the pyloric region and upper duodenum

Front 34

Gastrin stimulated by...

Back 34

food entering the stomach and thoughts of food

Front 35

Stomach emptying depends on...(3)

Back 35

1. Size and composition of the meal
2. pyloric sphincter rate of food entering the small intestine
3. Emotions

Front 36

Length of small intestine

Back 36

20 feet

Front 37

Order of small intestine

Back 37

1. Duodenum
2. Jejunum
3. Ileum

Front 38

Length of Duodenum

Back 38

12 inches

Front 39

Length of Jejunum

Back 39

8 feet

Front 40

Length of Ileum

Back 40

11 feet

Front 41

Small intestine is the main sight of...

Back 41

digestion and absorption of water, vitamins, minerals, sugars, fats and proteins

Front 42

Secretions to aid in digestion in small intestine:

Back 42

1. Bile-emulsifies fat
2. Pancreatic juice-
3. Intestinal digestive enzymes-breaks down proteins and sugars into single units

Front 43

Brush border enzymes

Back 43

intestinal digestive enzymes, microvilli

Front 44

Inner surface of intestine covered in ____ which are covered in _____

Back 44

Villi; microvilli

Front 45

Each villus contains a _____ and a ______

Back 45

blood vessel; lymph vessel

Front 46

Peristalsis

Back 46

Ring of contraction that propels material through the GI tract

Front 47

Segmentation

Back 47

Back-and-forth action that breaks down the food

Front 48

Mass movement

Back 48

Peristaltic wave that contracts over a large area of the large intestine to help eliminate waste

Front 49

Liver produces ____

Back 49

bile

Front 50

Gallbladder releases____ into _____

Back 50

bile into small intestine

Front 51

CCK signals

Back 51

to release bile and enzymes into small intestine

Front 52

All enzymes are...

Back 52

proteins

Front 53

Enzymes convert____ into____

Back 53

substrates into products

Front 54

CCK stimulates

Back 54

gallbladder to release bile and pancreatic enzymes

Front 55

Passive diffusion

Back 55

Intestinal wall is permeable
Going from high concentration to lower concentration
No energy required

Front 56

Facilitated diffusion

Back 56

Carrier shuttles substances into the absorptive cells
Going from high concentration to low concentration
No energy expanded

Front 57

Active transport

Back 57

nutrients carried across cell membrane
Requires ATP energy

Front 58

Osmosis

Back 58

water equilibriate level of salts against membranes