Biology - Chapter 11.8: Digestive System

Question 1

Salivary Amylase

Answer 1

• produced by salivary glands in mouth

- starch –> maltose

Question 2

Epiglottis

Answer 2

-Blocks the opening to the trachea, preventing choking

Question 3

Stomach

Answer 3

• food enters via cardiac sphincter
• mechanical and chemical breakdown of protein and fat occurs
• gastric and mucous gland cells
• food entry causes stomach to distend, signaling G cells to released gastrin

Question 4

Gastrin Functions

Answer 4

1) Stimulates parietal cells to release acidic gastric juice
2) Stimulates chief cells to secrete gastric lipase (breaks down fats) and pepsinogen (activated to pepsin that cleaves peptide bond)

Question 5

Small Intestine 3 Parts

Answer 5

Duodenum (digestion) > jejunum > ileum (absorption)

Question 6

Goblet cells

Answer 6

-Secrete mucus to protect the epithelial lining from acidic chyme

Question 7

Secretin

Answer 7

• Triggered by the release of chyme

- Stimulates pancreas to release bicarbonate ions into the duoden via pancreatic duct

Question 8

CCK

Answer 8

• Cholecystokinin
• Released by small intestine
• slows gastric emptying, stimulates pancreas to release digestive enzymes and gallbladder to release bile

Question 9

Bile

Answer 9

• emulsifies fat

- produced by liver and stored and concentrated by gallbladder

Question 10

Pancreatic Secretions

Answer 10

• HCO3-
• Pancreatic amylase (starch -> maltose)
• Proteases (proteins -> amino acids)

Question 11

Pancreatic Proteases

Answer 11

• zymogens first (trypsinogen and chymotrypsinogen)

- Trypsin and chymotrypsin

Question 12

Liver: Blood Maintenance

Answer 12

• Stores blood
• Filters and detoxifies blood
• Destroys erythrocytes and bacteria

Question 13

Liver: Glucose Metabolism

Answer 13

• Glycogenesis - converts excess glucose into glycogen
• Glycogenolysis - breaks down glycogen to glucose
• Gluconeogenesis - converts glycerol and amino acids into glucose when glycogen is depleted

Question 14

Liver: Protein Metabolism

Answer 14

• Synthesizes plasma proteins from amino acids (albumin and other blood clotting factors)
• Converts ammonia (dangerous byproduct) to urea for excretion

Question 15

3 Functions of Large Intestine

Answer 15

1) Water absorption
2) Mineral absorptions (salts)
3) Vitamin production and absorption: with mutualistic bacterial relationship, produces Vitamin B and K, bile acid and ferment fiber