What happens in the stomach? Absorption & Digestion

Question 1

The digestive system is responsible for the movement:

Answer 1

of nutrients into the body

Question 2

Synthesizing compounds is

Answer 2

anabolism

Question 3

Breaking down compounds to provide energy

Answer 3

catabolism

Question 4

Two main parts of the digestive system are

Answer 4

1. digestion
2. absorption

Question 5

What are the accessory organs of the digestive system?

Answer 5

salivary gland
Liver
Pancreas
Gallbladder

Question 6

The accessory organs produce _____, _____ and _____ ______ that contribute to the breakdown of food

Answer 6

bile, saliva, digestive enzymes

Question 7

Salivary glands : Secretion of _________ _______ containing enzymes that break down carbohydrates

Answer 7

lubricating fluid

Question 8

Liver: Secretion of _____ (important for lipid digestion), storage of nutrients, many other vital functions

Answer 8

bile

Question 9

Gallbladder: _______ and concentration of bile

Answer 9

storage

Question 10

Pancreas: Exocrine cells secrete _____ and digestive enzymes; endocrine cells secrete hormones

Answer 10

buffers

Question 11

Transit time:

Answer 11

amount of time it takes food to pass the length of the gastrointestinal tract, (time it takes for food to pass from mouth to anus).

Question 12

Food Disassembly

______ and ______ processes deconstruct food into polymers
(macromolecules: CHO, Lipids, protein nucleic acid)

These further breakdown into __________

Answer 12

chemical and mechanical

Question 13

GI tract & accessory organs work together in 6 steps:’

I
P
M
C
A
E

Answer 13

1. Ingestion (oral cavity)
2. Propulsion (pharynx, esophagus, stomach)
3. Mechanical Breakdown (stomach)
4. Chemical Digestion (accessory organs)
5. **Absorption (small intestine)
6. Elimination (large intestine)

Question 13

Mechanical refers to:

Answer 13

using smooth muscle

Question 14

Chemical refers to:

Answer 14

being enabled by accessory organs

Question 15

Layers of GI tract

Plica Circulares: Folds increase _______ _______ for ________

Answer 15

surface area, absorption

Question 16

Mucosa

Secretes ____

Absorption & ________

Answer 16

mucus
protection

Question 17

Submucosa: Rich supply elastic fibers that enable stomach to regain ______ _______ after storing large meal

Answer 17

regain the normal shape

Question 18

Muscularis externa:
Muscularis mucosae:

Smooth muscle cells involved with ________ materials along digestive tract (peristalsis)

Answer 18

moving

Question 19

Serosa (visceral peritoneum)

Answer 19

Protective covering of muscularis externa

Question 20

Path of Ingested Food: From Oral Cavity to Stomach

Question 21

Mastication

Chewing (mastication) helps to do what to surface area?

Answer 21

Chewing helps to INCREASE surface area so its easier for enzymes to attach on. Bolus is then created.

Question 22

Mastication

Saturates food with _______ ____/______

This forms a ________ and is swallowed

Answer 22

salivary secretions/enzymes

Bolus

Question 23

Saliva

what is produced by saliva INITIATES the start of the breakdown of ______ _________

Answer 23

salivary amylase

complex carbohydrates

Question 24

What is produced by the tongue that for the breakdown of ________

Answer 24

lingual lipase lipids

Question 25

T/F Absorption DOES NOT occur in the oral cavity?

Answer 25

T

Question 26

Pharynx connects to what?

Answer 26

Esophagus

Question 27

What is the passage way for solid food, liquids, air from oral cavity to esophagus

Answer 27

Pharynx

Question 28

Esophegeal sphincter:

Answer 28

prevents heartburn

Question 29

Ingested substances combine with secretions of glands of stomach to form

Answer 29

chyme

Question 30

Once bolus reaches the stomach, it forms into

Answer 30

chyme

Question 31

functions of the stomach S M C I

Answer 31

Storage Mechanical breakdown Chemical breakdown Production of intrinsic factor

Question 32

intrinsic factor (glycoprotein) : Required for intestinal absorption of

Answer 32

vitamin B12

Question 33

4 parts of the stomach

Answer 33

Fundus, Body, Pylorus, Cardia

Question 34

Fundus and Body: Gastric Glands Secretes ________ (prevents stomach from being digested)

Answer 34

muscus

Question 35

Fundus and Body: Gastric Glands Parietal cells: secretes ____ ____ (required for absorption of vitamin B12) & _______ _____

Answer 35

intrinsic factor, hydrochloric acid (HCL)

Question 36

Chief cells: produces __________(makes _______ when combined with ______ -> digests proteins)

Answer 36

pepsinogen, pepsin, HCL

Question 37

Pylorus: Pyloric Glands secrete ______

Answer 37

mucous

Question 38

Pylorus: Pyloric Glands G-cells: secretes ________ (stimulates parietal cells to secrete HCl)

Answer 38

gastrin

Question 39

D-Cells: secrete _________ (inhibits release of gastrin)

Answer 39

somatostatin

Question 40

What does the secretion of gastrin from g-cells do?

Answer 40

stimulates parietal cells to secrete HCL. This HCL is super important because HCL binds with pepsinogen to make pepsin, which is then used to digest proteins.

Question 41

stomach protects itself from self digestion using a ______ _______

Answer 41

mucosal barrier

Question 42

ACID reflux from stomach backs up into _________ Under normal conditions your ________ _________

Answer 42

esophagus esophageal sphincter

Question 43

Summary: Digestion from Oral Cavity to Stomach Salivary amylase & lingual lipase – digestion of _________ Pepsin digestion of the _______

Answer 43

CHO and lipids proteins

Question 44

As ph decreases, pepsin activity _________, this is when what begins

Answer 44

increases protein disassembly

Question 45

are nutrients absorbed in the stomach?

Answer 45

NOOOO

Question 46

CHO, lipids, proteins only ________ broken down in the stomach

Answer 46

partially

Question 48

Stomach Emptying Large meal: more ________ will stimulate release of _____ ______ and gastric motility. Therefore, gastric emptying is ________ Small meal: absence of ________, little stimulus for gastric motility; gastric emptying ________

Answer 48

distension gastric juice Fast distensions slow

Question 49

What stimulates gastric juices and motility?

Answer 49

distension

Question 50

What is the main source of digestion and absorption?

Answer 50

small intestine

Question 51

Duodenum What is released in response to chyme arrival (esp. when high in lipids) released in response to chyme arrival secreted when exposed to large quantities of incompletely digested proteins

Answer 51

Cholecystokinin (CCK): secretin pepsin

Question 52

Gallbladder stores what ?

Answer 52

Bile

Question 53

Bile necessary for ________of dietary fats

Answer 53

emulsification

Question 54

Emulsification is when fats are physically ______ into small little fat droplets

Answer 54

separated

Question 55

Emulsification also increases _______ _______ so enzymes can act on them

Answer 55

surface area

Question 56

If gallbladder removed:

Answer 56

bile production continues but is more dilute and entry into small intestine not closely tied to arrival of food in duodenum

Question 57

explain why bile is important in 4 steps:

Answer 57

1. Liver secretes bile 2. Bile becomes more concentrated the longer it remains in the gallbladder. 3.The release of cck by the duodenum triggers contraction of the gallbladder and opening of a sphincter. the ejects bile into the duodenum 4. Bile salts then break down lips droplets through a process called emulsification.

Question 58

Hormone CCK is secreted in response to what arrival at the duodenum?

Answer 58

chyme

Question 59

When is bile released into the duodenum?

Answer 59

under stimulation of CCK

Question 60

Pancreatic enzymes

Answer 60

- Pancreatic alpha-amalyse - Pancreatic lipase Proteolytic enzymes

Question 61

- Pancreatic alpha-amalyse breaks down what? - Pancreatic lipase breaks down what? Proteolytic enzymes breaks down what?

Answer 61

starches - lipids -proteins

Question 62

Pancreatic duct (enzymes, buffers) and common bile duct (bile) empty into ______ ______ - chemical digestion of food stuffs

Answer 62

duodenal ampulla

Question 63

Segmentation:

Answer 63

chyme moved back/forth few cm at a time by alternating contraction & relaxation of rings of smooth muscle. This mixes the chyme with bile, pancreatic, and intestinal juices

Question 64

The Small Intestine **ABSORPTION** Where does 90% of absorption occur?

Answer 64

small intestine

Question 65

Structural Modifications of Small Intestine to Increase Surface Area for **ABSORPTION** Plicae circulares: deep circular folds Villi: Microvolli:

Answer 65

increase surface area for absorption fingerlike extensions of the mucosa tiny projections of absorptive mucosal cells’ plasma membranes

Question 66

What enzymes are embedded in microvilli? What do they do?

Answer 66

brush border enzymes finish the digestion of CHO and proteins in the small intestine

Question 67

What happens in the duodenum? Jejunum? Illeum?

Answer 67

chemical digestion Nutrient absorption Vitamin absorption

Question 68

Where does nutrient absorption occur in the small intestine?

Answer 68

Jejunum

Question 69

Most digestion happens in what part of the small intestine

Answer 69

duodenum

Question 70

Large intestine moves what to the anus for defecation?

Answer 70

fecal material

Question 71

Large intestine has what important function?

Answer 71

reabsorption of water

Question 72

How much absorption happens in the large intestine?

Answer 72

<10%