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Flashcards in Metabolism 3. Deck (23)
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1

What effect does increased insulin level have on lipid metabolism?

- stimulates lipogenesis

2

Lipolysis is the conversion of _______________ to
___________________________.

triglycerides to fatty acids and monoglycerides (or glycerol)

3

Circle any of the following that result in increased ATP formation?
a. lipogenesis
b. lipolysis
c. β-oxidation
d. transamination
e. glycogenesis

- lipolysis
-B-oxidation

4

Briefly explain how ketones are formed and when they are formed in the body (2 marks).

ketones are formed as byproducts of lipolysis as 2 C are removed from fatty acids
- they occur during long fasts or when there is insufficient insulin released

5

Which of the following is NOT true of ketosis
a. occurs in most cells of the body
b. occurs as a result of β-oxidation
c. occurs as a result of protein catabolism
d. occurs as a result of starvation
e. occurs as a result of insulin insufficiency

a. occurs in most cells of the body

6

At each step in the catabolism of a fatty acid
a. a single carbon is removed as carbondioxide
b. 2 carbons are removed as acetyl
c. 3 carbons are removed as pyruvic acid
d. 3 carbons are removed as malonic acid
e. 3 carbons are removed as acetyl and carbon dioxide

b. 2 carbons are removed as acetyl

7

Formation of ketones occurs primarily in the ____________ (organ).

liver

8

Which of the following three substances are classified as ketone bodies by
physiologists?
a. lactic acid, glucose and pyruvic acid
b. acetoacetate ,acetone and β-hydroxybutyrate
c. fatty acids, acetoacetate and acetone
d. fattyacids, glycerol and palmitic acid
e. citric acid, lactic acid and pyruvic acid

b. acetoacetate, acetone and β-hydroxybutyrate

9

50.List three hormones (or kinds of hormones) that stimulate lipolysis, in the order in which they would be released in the body after ceasing food intake.

-glucagon
- adrenaline and noradrenalin
- corticosteroids

10

Describe the general structure of lipoproteins, mentioning their three main components and the function of each (3 marks).

- spherical particle
-triglycerides, fatty acids and cholesterol on the inside
-outer layer of phospholipids and proteins
- function in the transport of lipids from one tissue to another through the blood

11

Describe the function of chylomicrons and where they are formed (2 marks).

- formed in the lining of the small intestine
- transport lipids in the lymph to the blood

12

Describe the function of HDLs (high density lipoproteins) and where they are
formed (2 marks).

- formed as empty shells by the liver
- pick up excess cholesterol from many tissues and transport it to the liver

13

.Describe the function of LDLs (low density lipoprioteins) and where they are
formed (2 marks).

- transport cholesterol to tissues
- formed in tissues from VLDL

14

Describe the function of VLDLs (very low density lipoproteins) and where they
are formed (2 marks).

-transport fatty acids to tissues
- formed in the liver

15

Describe the process of transamination, its role in metabolism and where it
occurs (2 marks).

-transamination is the transfer of the amino group from one amino acid to a keto acid to form a new amino acid
- produces an amino acid that may be deficient in the diet
- occurs in the liver

16

Describe the process of deamination, its role in metabolism and where it
occurs.

- removes an amino group from an amino acid to form a keto acid
- keto acid enters the citric acid cycle to produce ATP

17

58.Name the waste product of deamination, describe its metabolic fate and explain why it is important that this waste product be managed efficiently (3 marks).

-ammonia is the waste product of deamination
- urea is formed from ammonia in the liver
- ammonia is toxic and can damage nervous tissue if it accumulates

18

The energy density (Calories per gram) of
a. carbohydrates is the same as that of lipids
b. carbohydrates is the same as that of proteins
c. lipids is half that of carbohydrates
d. proteins is twice that of lipids
e. proteins is the same as that of lipids

b. carbohydrates is the same as that of proteins

19

_______________ can be used by the citric acid cycle
a. only carbohydrates
b. only lipids and proteins
c. only carbohydrates and lipids
d. only carbohydrates and proteins
e. carbohydrates, lipids and proteins

e. carbohydrates, lipids and proteins

20

Explain what the basal metabolic rate (BMR) is and how it is measured (2 marks).

-BMR is the number of calories needed to support only the essential activities of the body
- it can be calculated be measuring the oxygen consumed by a subject who is remains calm and motionless, has not eaten and does not need to work to maintain body temperature

21

List one thing that can increase BMR and one thing that can decrease BMR.

-BMR is increased by the hormone thyroxine or by increasing the amount of muscle in the body
- BMR decreases with age

22

Explain what the VO2 max is and how it is measured (2 marks).

-VO2 max is the maximum rate of oxygen consumption
- measured by having subject run on a treadmill to exercise as strenuously as possible and measure their rate of oxygen consumption

23

List one thing that can increase VO2 max

VO2 max can be increased by increasing the ability of the lungs to absorb oxygen or increasing the efficiency of the cardiovascular system