Metabolic Integration

Question 1

Regulator of GLUT4?

Answer 1

Insulin; it insulin binds to it when blood glucose levels are high

Question 2

Where can each of the GLUT transporters be found?

Answer 2

GLUT2 is found in the liver; GLUT3 is found in the brain; GLUT4 is found in the muscle and adipose tissue

Question 3

What are all of the energy molecules circulating in the blood?

Answer 3

Glucose, lactate, glycerol, Fatty acids, ketone bodies, LDL OR CHYLOMICRON, amino acids

Question 4

What are the stored fuels in the body and in what amounts?

Answer 4

1. Glycogen–stored in liver (100-200g) and in muscle (200-400g)
2. TAGs–stored about 15000g but can be stored in essentially unlimited amounts
3. Proteins–6,000g, but no storage form independent from function

Question 5

What is the caloric value of carbs, TAGs, and proteins?

Answer 5

4,9,4

Question 6

Metabolism of brain cells

Answer 6

Fed state:
Aerobic glycolysis

Fasting state:
Glucose (gluconeogenesis and glycogenlysis)
Ketone bodies

Question 7

What is the calculation for BMI?

Answer 7

body weight in kilograms/height in meters squared

Question 8

Metabolism of fat cells (adipocytes)

Answer 8

Fed state:
Glucose (glycolysis, pyruvate–” acetyl coa) DHAP, PPP–R5P+ NADPH)
Fatty acids–“TAGs

Fasting state:
TAG –HSL–> FA + Glycerol (TAG degradation)

Question 9

Metabolism of myocytes

Answer 9

Fed state:
Glycolysis: anaerobic--> lactate, ATP
                   aerobic--> CO2, ATP 
Glycogen synthesis: Glucose-->Glycogen
Fatty acids-->CO2, ATP

Fasting State: 
Glycogen--> G6P-->CO2+ATP
Fatty acids--> CO2+ATP
Ketone bodies--> CO2+ATP
Proteins--> amino acids-->glucose (liver)

Question 10

Metabolism in hepatocytes

Answer 10

Fed state: 
Glucose--> CO2+ATP
Glucose--> glycogen
Fatty Acids--> CO2+ATP
                  -->TAG
Amino acids-->proteins
                     -->CO2, ATP, urea

Fasting States
Glycogen-->glucose
Gluconeogenesis--> glucose
Fatty acids--> CO2+ATP
                  -->ketone bodies
Amino acids--> glucose 
                    --> KBs, urea

Question 11

What is leptin secreted by?

Answer 11

Adipose tissue

Question 12

What does leptin do?

Answer 12

Regulates food intake by sending signals to the hypothalamus to eat less when fat stores are high
increases metabolic rate
decreases fat mass and body weight

Question 13

What is ghrelin secreted by>

Answer 13

An empty stomach

Question 14

What does ghrelin do?

Answer 14

It is a Growth Hormone RELease peptide which stimulates increased food intake and reduced fat utilization