Gastrointestal And Digestive System

Question 1

Function of GI tract?

Answer 1

To digest, absorb nutrients and provide protection

Secretion

Motility

Protection

Question 2

What are the 2 patterns of gastrointestinal smooth muscle contractility?

Answer 2

Segmentation contractions

Peristaltic contractions

Question 3

Explain peristaltic contractions

Answer 3

Moves food along gut in oral to anal direction

Move wave like along segments of gut

Happens in esophagus and small intestine

Question 4

Explain segmentation contractions

Answer 4

Mixing of food and that helps digestion and keeps it in contact with epithelium

Circular and longitudinal muscle contractions in segments of gut

Happens in small intestine

Question 5

Secreted substances include:

Answer 5

Enzymes

Mucus - mucus and goblet cells- protection of stomach lining

Water and electrolytes - gastro epithelial cells

Hcl - kills bacteria and activates pepsin

Pepsinogen- converts to pepsin to digest proteins

Question 6

What are the main digestion sites ?

Answer 6

Mouth

Stomach

Small intestine

Large intestine

Question 7

What is the reflex action in swallowing ?

Answer 7

Closure of epiglottis and opening of upper esophageal sphincter

Peristaltic wave down esophagus

Opening of lower esophageal sphincter

Question 8

Esophagus function

Answer 8

Secretes mucus

Moves food down throat using peristalsis movement

Question 9

Stomach function

Answer 9

Stores and breaks down food

Mixes food with digestive juices containing enzymes to break down protein and lipids

Acid kills bacteria

Question 10

Small intestine function

Answer 10

Has microvilli which has large surface area for absorption

Secretes digestive enzymes

Question 11

Large intestine function

Answer 11

Accepts what small intestine doesn’t absorb

Bacterial digestion, protein breakdown and absorbs more water and concentrates water and storage
Ferments carbohydrates

Question 12

Liver structure

Answer 12

Helps digestion by producing bile which helps digest fats and filters toxins and waste including alcohol and drugs

Surrounded by fibrous capsule and has numerous lobes and have cells called hepatocyes

Question 13

Functions of liver include

Answer 13

Nutrient storage and release

Bile production and secretion

Plasma protein synthesis

Cholesterol synthesis

Breakdown of erythrocytes

Question 14

How does the liver store nutrients ?

Answer 14

Hepatocytes absorb and store excess nutrients in blood like glucose, iron vitamin a and vitamin D

The nutrients are released when levels are low

Question 15

Gall bladder function

Answer 15

Stores bile from liver and releases into small intestine

Fatty diets can cause gall stones

Question 16

Pancreas function

Answer 16

Produces digestive enzymes to digest fats, carbohydrates and proteins

Regulates blood sugar by producing insulin

Question 17

What are the digestive enzymes produced in pancreatic juice ?

Answer 17

Lipase
Amylase
Chymotrypsinogen- by trypsin
Nuclease
Trypsinogen
HCO3

Question 18

What are the 2 pathways in the body for reabsorbed materials ?

Answer 18

Hepatic portal system which carries nutrients to liver

Enterohepatic circulation which recycles bile salts