XPhys Exam 1

how many kcal is a carb

4

how many kcal is a fat

9

how many kcal is a gram of protein

4

What type of exercise are carbs used the most

intense

what is gluconeogenesis

making new glucose in liver

what is glycogenolysis

breaking down glycogen

where is glycogen stored the most

skeletal muscle

What 3 places is glycogen stored?

liver, skeletal muscle, plasma glucose

how much carbs should a physically active person eat?

400-600g (60% daily total)

how much carbs should an althlete eat?

70% of total kcal

how does carb loading impact exercise

you can exercise at a higher intensity for longer

what does carb depletion do to fat and protein use

increases it

where are lipids stored? (4)

adipose tissue, intramuscular triglycerols, plasma FFA, and plasma TGs

how much fat intake is recommended?

20-35% of kcals

as exercise duration increases, fat use (increases/decreases)?

increases

what is the best intensity to burn fat

low intensity

how does fat / carb use change with training?

after training more fat is used first

how much protein intake is recommended?

0.8-2.0/ kg/ day

when does muscle protein synthesis occur the most

during recovery from exervise

what types of reactions are important in the ETC for resynthesizing ATP?

Redox

What are 4 factors that affect the rate of energy conversion?

enzymes, coenzymes, availability of substrates, and environmental factors

energy released form macronutrients gets used to…

rephosphorylate ATP

What are teh 3 energy systems for resynthesizing ATP?

ATP-PCr, glycolysis, and oxidative phosphorylation.

What does the relative contribution of the 3 energy systems depend on?

macronutrient availbility, exercise intensity, and need for energy

label A, B and C

A= glycolysis, B=oxidative phosphorylation, C= ATP-PCr

() systems produce energy faster than () systems

anaerobic; aerobic

anaerboic systems produce (more/less) energy than aerobic systems

less

energy systems/ processes producing the most E are located in the () of cells

mitochondria

T/F All energy systems are functioning all the time

True

Where does ATP-PCr occur?

in cytosol of muscle cells

What is the main enzyme in ATP-PCr

creatine kinase

Resting ATP stores would sustain resting energy needs for only ….

1-2 min

what are the reactants in ATP-PCR

ADP and creatine phosphate

resting PCr stores are ( ) resting ATP stores

the same as

What is the theory behind creatine supplementation

increased creatine can increase PCr levels increasing the duration of time that ATP-PCR supplies majority of energy during high-intensity activity.

T/F - creatine supplementation has an immediate effect?

false; it takes time to build stores

what enyme turns 2 ADP to ATP and AMP

Adenylate kinase

How many steps in glycolysis for glucose?

10

how many steps in glycolysis for glycogen

9

is glycolysis anaerobic or aerobic?

anerobic

where does glycolysis occur

cytosol

What is the first step of glycolysis?

glucose to G6P

what turns glucose into G6P

hexokinase

G6P turns to ____ in glycolysis?

fructose 6-P

what turns G6P to fructose 6P

glucose 6-phosphate isomerase

what does fructose 6-P turn into

fructose 1,6 bisphosphate

What turns fructose 6P to fructose 1,6 P

phosphofructokinase

what does fructose 1,6 P turn into

dihydroxyacetone phosphate and glyceraldehyde 3-phosphate

what turns dihydroxyacetone phosphate into glyceraldehyde 3-phosphate?

triosephosphate isomerase

What breaks apart fructose 1,6 bisphosphate into glyceraldehyde 3-phosphate?

aldolase

glyceraldehyde 3-phosphate turns into what next, and by what enzyme?

1,3 bisphosphoglycerate; glyceraldehyde 3-phosphate dehydrogenase

1,3 BPG turns into what next?

3-phosphoglycerate

what turns 1,3 BPG into 3-PG?

phosphoglycerate kinase

3-PG turns into what; by what enzyme?

2-phosphoglycerate by phosphoglyceromutase

2- PG turns into phosphoenol pyruvate by what enzyme

enolase

2 PG turns into what next?

phosphoenolpyruvate

PEP turns into what next>

pyruvate

what turns PEP to pyruvate?

pyruvate kinase

in what steps of glycolysis is ATP USED?

glucose to G6P , F6P to F1,6 BP (hexokinase and phosphofructokinase)

In what steps of glycolysis is ATP MADE?

1,3 BPG to 3PG and PEP to pyruvate (kinases)

What steps is NADH made in glycolysis?

G3P to 1,3 BPG

Each glucose when fully broken down forms two

lacatate or acetyl-CoA

what is the rate limiting enzyme of glycolysis

phosphofructokinase (PFK)

what is the net gain of glycolysis from glycogen?

3 ATP

what is the net ATP gain of glycolysis from glucose?

2 ATP

what affects the rate of ATP-PCr

the levels of PCr

() and () affect the rate of glycolysis

PFK, and glucose/glycogen storage

about () % of the potential energy in glucose is ultilized to produce ATP in glycolysis

3-5

how many atp does ATP-PCr yield

1

without sufficient oxygen glucose is converted to

lactate

what enzyme converts pyruvate to lactate

lactate dehydrogenase

where does lactate go durign exercise?

stays in muslce, and is transported to blood

what buffers lactate in blood?

bicarbonate

after cessation of exercise lactate is

converted back to glucose or used for energy

in the liver lactate can be

convered to glucose (stored as glycogen)

what two tissues can use lactate as energy?

brain and heart

When there is suffient oxygen pyruvate is converetd to ( ) by ( )

acetyl CoA; pyruvate dehydrogenase complex

how many atp is made from krebs?

2 (1 per cycle)

how many NADH frm glycolysis?

2

how many NADH from Krebs

6

how many FADH2 from Krebs

2

how many NADH from pyruvate→ acetyl coa

2

what is the rate-limiting step in Krebs?

isocitrate dehydrogenase

acetyl-coa combines with ( ) to make ( )

oxaloacetate; citrate

what turns acetyl coa and oxaloacetate into citrate?

citrate synthase

what does citrate turn into before isocitrate

cis-aconitate

what does citrate ultimately convert to ; by what enzyme?

isocitrate; aconitase

isocitrate converts to

oxalosuccinate

isocitrate —> oxalosuccinate by which enzyme?

isocitrate dehydrogenase

what does isocitrate ultimately convert to

alpha-ketogluterate

what turns isocitrate to a-ketogluterate

isocitrate dehydrogenase

what does a-ketogluterate turn into

succinyl-coa

what enzyme a-ketogluterate—> succinyl coa

a-ketogluterate dehydrogenase

succinyl coa turn into what; by what enzyme

succinate; succinyl-coa synthetase

succinate turns into ( ) by ( )

fumerate; succinate dehydrogenase

what does fumerate turn into

malate

what turns fumerate —> malate

fumerase

malate turns into

oxaloacetate

what enzyme converts malate—> oxaloacetate?

malate DH

in what step of krebs in ATP made?

succinyl coa—> succinate