Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Exsc 463 Final > Chapter 26 > Flashcards

Chapter 26 Flashcards

1
Q

Metabolism?

A

sum of all physical and chemical changes or rxns occurring in an organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Catabolism?

A

breakdown of large energy containing biomolecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are three catabolic pathways?

A
  1. Glycogenolysis and Lipolysis
  2. Aerobic and Anaerobic Glycolysis
  3. Beta Oxidation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Anabolism?

A

energy consuming process that results in the synthesis of larger molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are three anabolic pathways?

A
  1. Glycogenesis
  2. Gluconeogenesis
  3. Lipogenesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Three types of biomolecules, or energy substrates?

A

carbs
lipids
proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Bioenergetics?

A

study of the exchange or transfer of energy within biomolecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

1st Law of Thermodynamics?

A

conservation of energy, energy cannot be created nor destroyed, it can only be changed from one form to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Exergonic?

A

release energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Endergonic?

A

consume energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the usable form of carbs?

A

glucose, dietary carbs are digested and absorbed in the blood as glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In muscle, how is glucose transported across the sarcolemma?

A

by the insulin dependent GLUT-4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In the kidney and liver, how is glucose transported across the cell membrane?

A

GLUT-2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

In neurons, how is glucose transported into the cell?

A

GLUT-3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens immediately after glucose enters the muscle cell? reversible? why?

A
  • it is phosphorylated to G6P (P group added to carbon 6)

- this step is irreversible b/c muscle lacks the enzyme to convert it back

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Can G6P be transported out of the cell?

A

No, it is stored and used only in that cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Once glucose enters the cell and is phosphorylated to G6P, what two paths can it take?

A
  1. Glycolysis

2. Glycogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glycolysis?

A

metabolism of glucose to pyruvate, resulting in the resynthesis of ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What 2 things could happen to pyruvate after glycolysis?

A
  1. converted to lactate for anaerobic glycolysis

2. enter mitochondria for aerobic glycolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Glycogen is stored in higher concentrations in the skeletal muscle or the liver?

A

liver (100-120g stored after a meal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How much glycogen is stored in untrained skeletal muscle?

A

15g/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Glycogenesis?

A

formation of glycogen from many glucose molecules, it is the storage form of carbs

23
Q

Glycogenolysis?

A

to use glycogen, it is broken down into glucose in the liver and G6P in muscle

24
Q

Liver Glycogenolysis? Enzyme necessary?

A
  • liver has the enzyme, G6-phosphatase, which passes glucose back into the blood to be transported to any cell in the body
  • liver maintains blood glucose levels within a normal range
25
Q

Sub sarcolemmal glycogen?

A

glycogen stored below the muscle fiber membrane constitutes 5-15% of muscle glycogen

26
Q

Intra-myofibrillar glycogen?

A

glycogen stored within the myofibril constitutes 10-20% of muscle glycogen

27
Q

Inter-myofibrillar glycogen?

A

glycogen stored between myofibrils within the muscle fiber constitutes 70-80% of muscle glycogen

28
Q

Difference between type I muscle fibers and type II with glycogen storage?

A

type II store more glycogen in the inter-myofibrillar space and less in other place in comparison with type I

29
Q

How much carb storage is available to the body in total?

A
  • Blood glucose: 5 g
  • Liver: 100 g
  • Muscle: 450 g

Total: 555 g or 2220 kcal

30
Q

Hypoglycemia?

A

low blood sugar, less than 50 mg/dL of blood

31
Q

With a limited carb storage, how do athletes compete in prolonged events?

A
  • carbs are not the only energy substrates
  • fat is used in particular during endurance events
  • proteins, to a lesser extent
  • nutrition
32
Q

Glycogen loading?

A

increase the amount of carbs stored in your body (muscle) prior to endurance exercise with a high carb diet

33
Q

What does consuming carbs during exercise help with?

A

maintain blood glucose

34
Q

Why is carb the preferred energy substrate during exercise?

A
  1. glycogen stored in skeletal muscle is readily available, no need to enter the cell
  2. glucose and glycogen can be metabolized aerobically or anaerobically
  3. compared to metabolizing fat, aerobic metabolism of carbs produces more ATP per O2 consumed
35
Q

In what form are fats stored in the body?

A

as triglycerides in adipose tissue and skeletal muscle, this is the most plentiful source of energy in the body

36
Q

What are triglycerides broken down into?

A

glycerol and fatty acids (long even numbered chain of carbons bound with hydrogen and O2)

37
Q

Lipolysis?

A

breakdown of a triglyceride to a glycerol and three fatty acids

38
Q

Lipogenesis?

A

formation of triglyceride from glycerol and three fatty acids

39
Q

In what form are fatty acids transported in the blood? How do they enter skeletal muscle?

A
  • as free fatty acids by albumin

- by simple or facilitated diffusion

40
Q

What happens to fatty acids once they are inside skeletal muscle?

A
  • they are transported into the mitochondria by carnitine transferase
  • then carbons are broken off two at a time(beta oxidation)
  • two C units undergo further metabolism to resynthesize ATP
41
Q

Beta Oxidation?

A

the cleaving of two carbon units from fatty acids in the mitochondria

42
Q

What happens to glycerol after lipolysis? Where does most of it go?

A
  • it is water soluble so it is transported in the plasma to active skeletal muscle cells or to the liver
  • glycolytic path if it enters the muscle
  • most glycerol goes to liver where it is converted to glucose (gluconeogenesis)
43
Q

Gluconeogenesis?

A

formation of glucose in the liver from noncarb sources, such as glycerol, lactate, and amino acids

44
Q

Four reasons why fats are important?

A
  1. triglycerides represent a significant source of potential energy
  2. using fatty acids has a glycogen sparing effect
  3. fat is a high density energy substrate (2.25 times the energy compared to carbs), anhydrous
  4. metabolism of fatty acids releases large number of hydrogens used in mitochondria to produce ATP
45
Q

What are the limitations to use fatty acids as energy substrates during exercise?

A
  1. aerobic metabolism of fatty acids produces less ATP per oxygen than with glucose, so fats contribute more at low intensity exercise
  2. To get fatty acids to skeletal muscle takes time
46
Q

Spot reduction? Is is truth?

A
  • do a particular exercise that reduces fat in certain areas

- not true due to lipolysis throughout the body stimulated by hormones

47
Q

How are proteins stored in the body as?

A

polypeptides

48
Q

How many essential amino acids? where do we get them?

A

9

from diet, not produced in body

49
Q

When proteins are used for energy, muscles prefer which ones?

A

branched chain amino acids like valine, leucine, isoleucine

50
Q

Deamination?

A

nitrogen group (NH2) is removed from amino acids to be used for energy, it becomes ammonia, happens primarily in liver

51
Q

Transamination?

A
  • transfer nitrogen group to form a new amino acid, pyruvic acid, acetyl CoA, or Krebs cycle intermediate
  • is converted to glucose in liver
52
Q

How is blood glucose maintained during exercise?

A
  1. liver glycogenolysis
  2. gluconeogenic conversion of lactate, glycerol, amino acids
  3. eating carbs during exercise
53
Q

Normal fasting blood glucose levels?

A

less than 100 mg/dL

5.5 mmol/L

glucose has molar mass of 180.16 g/mol

54
Q

1 gram carbs = ?
1 g of fat = ?
1 g of protein = ?

(kcal/g, kJ/g)

A

carb = 4 kcal/g = 16.8 kJ/g

fat = 9 kcal/g = 37.8 kJ/g

protein = 4 kcal/g = 16.8 kJ/g

Exsc 463 Final (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions