Lec 14 Aerobic Metabolism/fat Metabolism Flashcards
What are the four conditions that cause catabolic fat metabolism
Exercise, fasting state, hypoglycaemia, fight or flight
What are the four hormones that help with then breakdown and mobilization of fat
Adrenaline
Cortisol
Glucagon
Epinephrine
What processes does the lipid system involve
Lipolysis and free fatty acid uptake by muscles
Beta oxidation
Oxidative phosphorylation
What is the only lipid that is a major source of ATP and energy for muscles
Triglycerides
Lipid/ fat oxidation is __________ process
Aerobic
What is the structure of a triglyceride
Glycerol back bone with three ester bonds attaching three FFA tails
What occurs during lipolysis
Break down of triglycerides
Hydrolysis releases the attached FFA from the glycerol back bone
Eventually breaks down to just glycerol
What is the role of albumin
After lipolysis FFA are not water soluble so they cannot dissolve directly into the blood
Albumin Carrie’s theses FFA and transfers them in the blood to muscle and liver where why are used for energy
How are lipids uptaken?
How are they carried in the blood? How are they carried in the cell? How do they enter
ALBUMIN carries FFA inside the blood
Chaperoned by fatty acid binding protein aka FABP inside the cell
Enter the cell via carrier proteins or facilitated diffusion
How does FFA get into the mitochondria
FFA is converted to fatty acylcoA by fatty acylcoA synthase
Fatty acylcoA is the activated version of FFA
This process prevents FFA to leave the cell but TAKES 2 ATP
Carnitine is then used as a shuttle to bring fatty acylcoA inside the matrixs
What does role does carnitine play
Transfers of acetylCoa fatty acids across the inner mitochondrial membrane during lipolysis
Beta oxidations
How would you calculate number of cycles
Carbon length/ 2-1
During beta oxidation what happens to carbon chain every cycle
Loses 2 carbons each cycle
During beta oxidation
What is involve, what are the inputs, outputs, etc.
Start with fatty acylcoA
Input
1 NAD+
1 FAD
Coenzyme A
output
1 NADH2
1 FADH2
Acetyl coA
GOES TO ETC
Beta oxidation
How many cycles, produces how many acetyl coa, how many FADH2 and NADH2
For a 18 carbon
What about 24 carbon
18 carbon - 8 cycles, 9 acetyl coA, 8 NADH2 and 8 FADH2
24 carbon - 11 cycles, 12 acetyl coA, 11 NADH2 and 11 FADH2
Why are the inputs and outputs of beta oxidation
What is left over
What happens after
Input - fatty acetylCoa, Fad, nad, coA
Output - acetyl coA, NADH, fadh2
Two carbon acetyl coA molecules are left over
Acetyl coA goes to TCA cycle
What yield more ATP carbohydrate oxidation or fat oxidation
Fat oxidation but it is slower
What is the P/O ratios for carbohydrates vs fat oxidation
What is the difference between ATP production for both and what is the difference is P/O
Carbohydrate oxidation = 2.67 and 32 ATP
Fat oxidation = 2.31 and 120 ATP
Carbohydrates produce less ATP but are more oxygen efficient and more economical (produce more ATP per molecule of O2)
Fat oxidation produces more ATP but are less oxygen effluent and less economical
Females typically have more ___________ muscle profiles than males
Oxidative
Females have a greater proportion of ________ muscle fibres than males
What’s the percentage
Type 1
7-23% of type 1
At the same exercise intensity
Female will ______________________ and less ________
Whereas males have a greater ________________
Females will oxidize more fat and less carbohydrates
Males have a greater Glycolytic capacity
Who has a slower muscle relaxation rate
Females
Females have lower rates of sarcoplasmic reticulum _____________________
Have lower rates of sarcoplasmic reticulum calcium atpase activity
Slightly weaker
They are more fatigue resistant than males
