Digestive System 1

Question 1

What are the four key functions of the digestive system?

Answer 1

Ingestion, Digestion (mechanical & chemical), Absorption, Elimination.

Question 2

What are macronutrients?

Answer 2

Carbohydrates, fats/lipids, and proteins.

Question 3

What are the two major anatomical components of the digestive system?

Answer 3

1) Gastrointestinal (GI) tract, 2) Accessory organs.

Question 4

What structures make up the gastrointestinal tract?

Answer 4

Mouth, oral cavity, oropharynx, oesophagus, stomach, small intestine, large intestine, rectum, anus.

Question 5

What are the accessory organs of the digestive system?

Answer 5

Teeth, tongue, salivary glands, liver, gallbladder, pancreas.

Question 6

How long is the GI tract?

Answer 6

~30 feet (9 meters).

Question 7

What is the function of the mucosa layer in the GI tract?

Answer 7

Secretes mucus, digestive enzymes, and hormones.

Question 8

What does the submucosa layer contain?

Answer 8

Blood vessels, lymphatic vessels, nerves, and glands.

Question 9

What is peristalsis?

Answer 9

Coordinated involuntary contraction and relaxation of circular and longitudinal muscles, moving food forward.

Question 10

What is segmentation in the GI tract?

Answer 10

Mixing movement where food is pushed back and forth, enhancing digestion and absorption.

Question 11

What is the role of the mouth in digestion?

Answer 11

Ingestion and initial digestion (mechanical and chemical).

Question 12

What is mastication?

Answer 12

The physical breakdown of food using teeth and tongue.

Question 13

What enzyme is found in saliva, and what does it do?

Answer 13

Amylase, which breaks down carbohydrates.

Question 14

What is the composition of saliva?

Answer 14

99.5% water, 0.5% amylase, bicarbonate ions, and electrolytes.

Question 15

What are the three main salivary glands?

Answer 15

Parotid, sublingual, and submandibular glands.

Question 16

What is the function of the oesophagus?

Answer 16

Transports swallowed food to the stomach.

Question 17

What is the role of the cardiac sphincter?

Answer 17

Prevents stomach contents from flowing back into the oesophagus.

Question 18

What are the three regions of the stomach?

Answer 18

Fundus, body, antrum.

Question 19

What is the function of the pyloric sphincter?

Answer 19

Regulates the passage of chyme from the stomach to the small intestine.

Question 20

What is the function of rugae in the stomach?

Answer 20

Ridges that allow stomach expansion and secretion of digestive acids and enzymes.

Question 21

How long does food stay in the stomach?

Answer 21

2-4 hours.

Question 22

What is the pH of the stomach?

Answer 22

Strongly acidic, around pH 1-3.

Question 23

What are the three sections of the small intestine?

Answer 23

Duodenum, jejunum, ileum.

Question 24

What happens in the duodenum?

Answer 24

Mixing of chyme with digestive secretions from the pancreas and gallbladder.

Question 25

What is the primary function of the jejunum?

Answer 25

Further digestion and absorption of nutrients.

Question 26

What is the role of the ileum?

Answer 26

Absorbs remaining nutrients before passing waste to the large intestine.

Question 27

What structures in the small intestine aid absorption?

Answer 27

Villi and microvilli increase surface area for nutrient absorption.

Question 28

How long is the small intestine?

Answer 28

3 to 5 meters (~10 to 20 feet).

Question 29

What is the primary function of the large intestine?

Answer 29

Absorption of water and electrolytes.

Question 30

What beneficial substances are produced in the large intestine?

Answer 30

Vitamins B12, thiamin, riboflavin, and vitamin K.

Question 31

What is the function of the caecum?

Answer 31

Starts water and electrolyte absorption and mixes mucus for stool lubrication.

Question 32

What is the rectum’s role?

Answer 32

Stores feces before elimination.

Question 33

What are the accessory organs involved in digestion?

Answer 33

Liver, pancreas, gallbladder.

Question 34

What is the primary function of the liver?

Answer 34

Metabolism, detoxification, storage, hormone synthesis, and bile production.

Question 35

What is the role of bile?

Answer 35

Helps digest fats by emulsifying them.

Question 36

Where is bile stored?

Answer 36

In the gallbladder.

Question 37

What are the two main functions of the pancreas?

Answer 37

Exocrine (enzyme secretion for digestion) and endocrine (hormone secretion for blood sugar regulation).

Question 38

What are the key digestive enzymes produced by the pancreas?

Answer 38

Amylase (carbs), lipase (fats), and trypsin (proteins).

Question 39

What are the islets of Langerhans?

Answer 39

Endocrine cells in the pancreas that regulate blood glucose (insulin and glucagon production).

Question 40

What is the function of the anal sphincter?

Answer 40

Controls the release of stool from the rectum.

Question 41

What are the four major functions of the digestive system?

Answer 41

Ingestion, digestion, absorption, and elimination.

Question 42

Where does most digestion and absorption occur?

Answer 42

Small intestine, specifically the ileum.

Question 43

What is the final step in digestion?

Answer 43

Elimination of undigested waste through the anus.