Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

1.1 POM Cells > Integration of Metabolism > Flashcards

Integration of Metabolism Flashcards

1
Q

How much of the total body weight is muscle?

A

40%

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

How much of the total body weight is brain and nervous tissue?

A

2%

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

How much of the total body weight is adipose tissue?

A

15%

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

How much of the total body weight is the heart?

A

1%

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

How much of the total body weight is the liver?

A

2.5%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is muscle ATP requirement like?

A

High during vigorous contraction

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

What is brain and nervous tissue ATP requirement like?

A

Continuously high —> 20% BMR

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

What is the heart’s ATP requirement like?

A

Constant —> 10% BMR

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

What is the liver’s ATP requirement like?

A

Constantly high —> 20% BMR

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

Which 2 energy sources do skeletal muscle and the heart rely on?

A
  1. Carbohydrates
  2. Fatty acid oxidation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which energy source does the brain and nervous tissue rely on?

A
  1. Glucose (needs continuous supply)
    - Ketone bodies can partially substitute
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why can’t the brain metabolise fatty acids?

A

Can’t cross blood-brain barrier

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

How does hypoglycaemia and hyperglycaemia affect the brain?

A
  • Hypoglycaemia —> faintness/coma
  • Hyperglycaemia —> irreversible damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the source of energy for muscles during light vs vigorous contraction?

A
  • Light —> oxidative phosphorylation
  • Vigorous —> glycogen breakdown and lactate formation (supplies NAD+ for glycolysis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What type of metabolism is the heart dependant on?

A

Aerobic

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

What happens to the heart when O2 is limited or energy demand > supply?

A

Cell death —> myocardial infarction

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

What are the 3 important functions of the liver for metabolism?

A
  1. Interconverts nutrient types
  2. Stores glycogen
  3. Lipoprotein metabolism (for triglyceride and cholesterol tranport)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What should blood glucose levels be maintained at?

A

4.0-5.5 mM

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

How does the body prevent hypoglycaemia? (3)

A
  1. Glycogenolysis
  2. Release free fatty acids from adipose tissue
  3. Ketone body production from acetyl CoA by the liver
20
Q

Which 3 molecules are important for gluconeogenesis?

A
  1. Lactate —> regenerate pyruvate via LDH
  2. Amino acids —> converted to TCA substrates
  3. Glycerol of triglycerides —> generates DHAP
21
Q

What is the ΔG of gluconeogenesis?

A

-38 kJ/mol

22
Q

Which bonds are needed to make gluconeogenesis energetically favourable and how many are needed?

A

6 Phosphoanhydride bonds

23
Q

What are the 6 steps of gluconeogenesis?

A
  1. Pyruvate —> oxaloacetate
    - Pyruvate carboxylase
  2. —> PEP
    - PEP carboxykinase
  3. —> F16BP
  4. —> F6P
    - F16BPase
  5. —> G6P
  6. —> Glucose
    - G6Pase
24
Q

How many ATPs are used in gluconeogenesis?

25
Which gluconeogenesis reactions use ATP?
1. Pyruvate ---> oxaloacetate -2 ATP 2. Oxaloacetate ---> PEP -2 GTP 3. PEP ---> F16BP -2 ATP
26
What are glucogenic amino acids?
Can generate glucose via gluconeogenesis
27
What are ketogenic amino acids?
Can generate ketone bodies and fatty acids (via generating acetyl CoA)
28
What 2 things does contracting muscle require?
1. inc ATP 2. inc Glucose transporters
29
Why is adrenalin secreted during increased muscle contraction?
1. Increases gluconeogenesis in liver 2. Increases fatty acid release from adipocytes
30
How is lactate involved in sourcing ATP when there is high demand? (2)
1. Lactate synthesis regenerates NAD+ for glycolysis 2. Lactate used in gluconeogenesis
31
What is The Michaelis Constant?
Concentration of of substrate at which enzyme functions at half Vmax
32
What is Km?
The Michaelis Constant (concentration of of substrate at which enzyme functions at half Vmax)
33
What is Vmax?
The maximum rate of an enzymatic reaction under saturated substrate conditions
34
Which hexokinase is used in muscle?
I
35
Which hexokinase is used in the liver?
IV
36
What is the difference between hexokinase activity in muscles vs the liver?
- Muscle HK I low ---> control glucose metabolism - Liver HK IV high ---> high G6P to G
37
What is the difference between the Km of muscles vs the liver?
- Muscle ---> 0.1 mM - Liver ---> 4 mM ∴ More substrate needed to reach Vmax for HK IV
38
What is the difference between G-6-P inhibition sensitivity in muscles vs the liver?
- Muscle ---> high - Liver ---> lower
39
When is insulin secreted and why?
When glucose levels rise - Stimulates glucose uptake - Stimulates glycogen and fat storage
40
When is glycogen secreted and why?
When glucose levels fall - Stimulates gluconeogenesis - Stimulates glycogen and fat breakdown
41
Which 3 processes is adrenalin important for in metabolism?
1. Glycogenolysis (liver) 2. Glycolysis (skeletal muscle) 3. Lipolysis (adipose tissue)
42
Why are glucocorticosteroids important for metabolism?
Increase synthesis of metabolic enzymes controlling glucose availability
43
How are blood glucose levels controlled when blood glucose is low? (not consuming glucose)
- Glucagon secretion inc - Insulin secretion dec
44
Which 4 metabolites are used during prolonged fasting and how?
1. Fatty acids - released by hydrolysis of triglycerides stored in adipose tissue 2. Amino acids - provide substrates for gluconeogenesis 3. Ketone bodies - can partially substitute brain's glucose requirements 4. TCA intermediates - for gluconeogenesis
45
What is Type 1 diabetes?
Failure to secrete sufficient insulin (B-cell dysfunction)
46
What is Type 2 diabetes?
Failure to respond appropriately to insulin (insulin resistance)
47
What are the 4 complications of diabetes?
1. Hypoglycaemia 2. Hyperglycaemia 3. Cardiovascular issues 4. Ketoacidosis

1.1 POM Cells (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions