aerobic metabolism (fat)

Question 1

where are the two sources of FFAs

Answer 1

in adipose tissues
inside the cell

Question 2

what is the pathway from adipose tissue to FFAs

Answer 2

adipose tissue (fat resources) are mobilised in the form of triglycerides by catabolic hormones

FFAs are hydrolysed from triglyceride one by one (lipolysis)

FFAs carried through the blood by albumin

Question 3

what are the 3 components of the aerobic system (lipid)

Answer 3

1. lipolysis and FFA uptake in skeletal muscle
2. beta oxidation
3. oxidative phosphorylation

Question 4

how do triglyceride stores change at rest and during exercise

Answer 4

stored during rest
used during exercise
replenished during rest

Question 5

what is the structure of triglycerides

Answer 5

glycerol backbone
3 ester bonds between FFAs and glycerol
3 FFA tails

Question 6

what is lipolysis

Answer 6

breakdown of triglycerides
hydrolysis (needs water) of attached FFA from the glycerol backbone

changes from tri to di to monoglyceride

Question 7

how are lipids transported

Answer 7

carried by albumin in the blood
(needs to be in the cell to be oxidised)
enter cell via carrier proteins or facilitated diffusion
chaperoned by fatty acid binding protein (FABP) (carries cell into the cell from blood)

Question 8

how do FFAs get into the mito

Answer 8

converted to fatty acetyl coa (activated FFA) by fatty acetyl coa synthase inside the cell
(can’t go back to triglyceride from here - needs to go into mito)
shuttled into mito by carnitine

Question 9

what is the function of carnitine

Answer 9

essential in the transfer of long chain fatty acids (fatty acetyl coa) across the inner mito membrane

(like the motorised thign that takes the line of carts into the grocery store)

Question 10

what is the difference in efficiency between carbs and fat

Answer 10

carbs are more efficient
need more O2 per molecule to oxidise fat

fat = greater source of energy but lower efficiency

Question 11

what characterstics do females show (opposite in males)

Answer 11

• more oxidative and fatigue resistant
• oxidise more fats than carbs
• slower muscle relaxation rate
• lower rates of SR Ca2+ ATPase activity (less calcium released and reuptaken by SR)
• greater mito respiration rates/content (better mitobiogenesis)
• higher capillary density
• greater vascular conductance and blood flow

Question 12

what do the sex differences (metabolic, contractile, and hemodynamics) suggest

Answer 12

females may be more suited to aerobic performance