Chapter 11: Lipids (Test 1)

Question 1

What are lipids?

Answer 1

• Molecules that are not soluble in water, but are in organic solvents

Question 2

What are the five classes of lipids?

Answer 2

• Free fatty acids
• Triacylglycerols
• Phospholipids
• Glycolipids
• Steroids

Question 3

Free fatty acids

Answer 3

• A common fuel

- Oxidized to make ATP

Question 4

Triacylglycerols

Answer 4

• The storage form of fatty acids

Question 5

Phospholipids

Answer 5

• Membrane lipids

Question 6

Glycolipids

Answer 6

• Membrane lipids composed in part of carbs

- The carb components are on the extracellular side for cell-cell recognition

Question 7

Steroids

Answer 7

• Polycyclic hydrocarbons with a variety of functions

Question 8

Saturated

Answer 8

• No double or triple bonds

Question 9

Unsaturated

Answer 9

• Contains double or triple bonds

Question 10

At physiological pH, fatty acids are referred to as their___ form

Answer 10

• Carboxylate

Question 11

When double bonds are present, they are commonly in the ___ config

Answer 11

• Cis

Question 12

The properties of fatty acids are dependent on?

Answer 12

• Chain length

- Degree of unsaturation

Question 13

What increases the fluidity of fatty acids?

Answer 13

• Short chain length

- The presence of cis double bonds

Question 14

What type of fatty acids are precursors to a variety of hormones and appear to offer some protection from coronary heart disease?

Answer 14

• Cis polyunsaturated fatty acids

Question 15

What is saponification?

Answer 15

• The creation of soaps treatment of triacylglycerols with a strong base

Question 16

Where in the major site of triacylglycerol storage?

Answer 16

• Adipose tissue (inside a large lipid droplet)

Question 17

Triacylglycerols contain more than ___ times the energy of a gram of glycogen

Answer 17

• 6

Question 18

What are the common types of membrane lipids?

Answer 18

• Phospholipids
• Glycolipids
• Cholesterol

Question 19

What is the major class of membrane lipids?

Answer 19

• Phospholipids

Question 20

What are the simplest glycolipids?

Answer 20

• Cerebrosides

Question 21

What is the most common steroid?

Answer 21

• Cholersterol

Question 22

Sphingolipids

Answer 22

• Contain a sphingosphine backbone
• Found in plants and animals
• Abundant in the nervous system

Question 23

Where are glycolipids derived from?

Answer 23

• Ceramides

Question 24

Androgens

Answer 24

• Male sex hormones
• Synthesized in the testes
• Responsible for secondary male sex characteristics
• Testosterone

Question 25

Estrogen

Answer 25

- Female sex hormones - Synthesized in the ovaries - Responsible for secondary female sex characteristics

Question 26

What does cholesterol do for cells?

Answer 26

- Reduce fluidity

Question 27

Vitamin A (retinol)

Answer 27

- Serves as the site of the primary photochemical reaction in vision - Active form is retinal

Question 28

Vitamin D

Answer 28

- Regulates calcium (and phosphorus) metabolism | - Most abundant form is vitamin D3 in the circulatory system

Question 29

Vitamin E

Answer 29

- Serves as an antioxidant

Question 30

Vitamin K

Answer 30

- Has a regulatory function in blood clotting

Question 31

Prostaglandins

Answer 31

- Have biological effects (e.g. promote inflammation)

Question 32

Thromboxane A2

Answer 32

- Produced by platelets - Stimulate blood vessel contriction - Coagulation

Question 33

Prostacyclin

Answer 33

- Reverse effects of Thromboxane A2