1.5 -- Digestive System Overview

Question 1

What is the largest immune organ, deals with digestion and absorption, and is the largest habitat for microflora (bacteria, algae, and fungi)?

Answer 1

Digestive system

Question 2

Digestion, secretion, motility, and absorption are the four functions of what?

Answer 2

Digestive system

Question 3

What is the wave-like, one-way movement through the tract?

Answer 3

Peristalsis

Question 4

What is the mixing and churning while moving forward?

Answer 4

Segmentation

Question 5

Digestive enzymes, hydrochloric acid, mucus, water, and bicarbonate are exocrine or endocrine secretions?

Answer 5

Exocrine secretions

Question 6

Hormones that regulate digestion are exocrine or endocrine secretions?

Answer 6

Endocrine secretions

Question 7

What are the four accessory organs of the digestive system?

Answer 7

Liver, gallbladder, pancreas, and salivary glands

Question 8

Do undigested materials like cellulose ever actually enter the body?

Answer 8

No

Question 9

Mucosa, lamina propria, muscularis mucosa, submucosa, muscularis propria, subserosa, and serosa are the what?

Answer 9

Layers of the digestive tract

Question 10

Which layer of the GI tract is a single layer of epithelium cells which functions for secretion/absorption and has enterocytes?

Answer 10

Mucosa

Question 11

Parasympathetic nervous system, sympathetic nervous system, and hormones are part of the intrinsic or extrinsic regulation?

Answer 11

Extrinsic regulation

Question 12

The enteric nervous system and paracrine signals are part of the intrinsic or extrinsic regulation?

Answer 12

Intrinsic regulation

Question 13

Can the enteric nervous system in the wall of the digestive tract work without connection to the CNS? Do they communicate via afferent/efferent connections?

Answer 13

Yes

Question 14

When chyme is broken into smaller particles, it does what to surface area?

Answer 14

Increases surface area

Question 15

The stomach functions to store what, make what, begins what digestion, kills bacteria in the food via what, and moves chyme into what?

Answer 15

Store food, make chyme, protein digestion, kills with acid, and moves chyme into the small intestine

Question 16

What cell type in the stomach secretes mucus to help protect stomach lining in the acid?

Mucous cell/Parietal cell/Chief cell

Answer 16

Mucous cell

Question 17

What cell type secretes hydrochloric acid and intrinsic factor which is required for absoprtion of vitamin B12?

Answer 17

Parietal cell

Question 18

What cell type secretes pepsinogen which is an active form or proteolytic enzyme?

Answer 18

Chief cell

Question 19

Creating an acidic environment in the stomach (pH 1-2), denature proteins, convert pepsinogen to active pepsin, and serve as an optimal pH for pepsin, which catalyzes hydrolysis of peptide bonds ingested proteins are the functions of what?

Answer 19

Hydrochloric acid

Question 20

Where does most digestion occur with complete digestion of carbohydrates, proteins, and fats? Where do exocrine secretions enter there?

Answer 20

Small intestine and enter at the duodenum

Question 21

What is folded into villi and microvilli between the epithelial plasma membrane and mucosa?

Answer 21

Mucosa – Villi
Epithelial Plasma Membrane – Microvilli

Question 21

What is the site of “brush border” enzymes?

Answer 21

Microvilli

Question 22

The villus is what sort of epithelium and has intestinal crypts filled with what sort of cell?

Answer 22

Simple columnar and stem cells

Question 23

Does the enterohepatic system recycle 95% bile salts to reuse while 5% is new as 5% is lost in feces?

Answer 23

Yes

Question 24

Does recycling the bile salts regulate hepatic synthesis of bile acids from cholesterol, and therefore, controlling plasma cholesterol levels?

Answer 24

Yes

Question 25

Which hormone secreted by the small intestine secrete water and HCO3- from the pancreas and raises pH of incoming chyme, allowing pancreatic enzymes to be active?

Answer 25

Secretin

Question 26

Which hormone secreted by the stomach stimulates parietal and Chief cells and maintain the structure of gastric mucosa?

Answer 26

Gastrin

Question 27

Which hormone secreted by the stomach is a pancreatic enzyme secretion that secretes bile via stimulation of gallbladder contraction, which is responsible for enzymatic digestive activity, fat emulsion stability, and absorption of digestion products of fat?

Answer 27

Cholecystokinin (CCK)