Digestive System

Question 1

What are catabolic reactions?

Answer 1

reactions that break down molecules

Question 2

What are anabolic reactions?

Answer 2

reactions that result in net energy storage within cells

Question 3

As temperature increases, chemical reaction rate ____.

Answer 3

increases

Question 4

What are endotherms?

Answer 4

animals that produce their own heat as byproducts of metabolic reactions

Question 5

What are ectotherms?

Answer 5

animals that obtain most of their heat from the environment

Question 6

While ____ maintain a steady body temperature, ____’ body temperature fluctuates with the environment

Answer 6

endotherms; ectotherms

Question 7

What is digestion?

Answer 7

the process of breaking down food into smaller molecules that can be absorbed into the body

Question 8

What are the four stages of digestion?

Answer 8

1. ingestion
2. digestion
3. absorption
4. elimination

Question 9

What is gastrin?

Answer 9

enzyme released by the stomach that stimulates HCl production

Question 10

What is pepsin?

Answer 10

enzyme that breaks down proteins

Question 11

What is lipases?

Answer 11

an enzyme that breaks down lipids

Question 12

What is trypsin?

Answer 12

enzyme that breaks down proteins

Question 13

What is secretin?

Answer 13

hormone released by duodenum that stimulates pancreas to secrete bicarbonate ions to neutralize stomach acid

Question 14

What is bile?

Answer 14

fluid produced by the liver and stored in the gallbladder that aids in fat digestion by emulsifying lipids

Question 15

What is CCK?

Answer 15

hormone released by duodenum that stimulates gallbladder to release bile into duodenum

Question 16

What happens in the mouth during digestion?

Answer 16

food is ingested and broken down mechanically and chemically by amylase and lipase

Question 17

What happens in the esophagus during digestion?

Answer 17

food travels from mouth to stomach thru the process of peristalsis

Question 18

What happens in the stomach during digestion?

Answer 18

1. food enters stomach
2. gastrin is released
3. HCl is produced to increase stomach acidity
4. pepsinogen is activated into pepsin
5. pepsin breaks down proteins and lipases break down lipids

Question 19

What happens in the small intestine during digestion?

Answer 19

1. duodenum secretes secretin to neutralize small intestine
2. chyme from stomach enters the small intestine thru duodenum
3. nutrients are absorbed into body

Question 20

What are chief cells?

Answer 20

cells in the stomach that secrete pepsinogen

Question 21

What are parietal cells?

Answer 21

cells that release H+ and Cl-

Question 22

How is pepsin activated in the stomach?

Answer 22

1. when food enters the stomach, parietal cells release H+ and Cl, which synthesize into HCl
2. chief cells secrete pepsinogen
3. high acidity activates pepsinogen → pepsin
4. as pepsin levels rise, more pepsinogen is secreted

Question 23

How do glucose and Na+ enter the intestinal cell from the lumen?

Answer 23

Na+/glucose cotransporters

Question 24

How does glucose exit the intestinal cell into the extracellular fluid/blood?

Answer 24

glucose transport protein