2 energy expenditure

metabolism=

series of chemical reactions in a living organism that create and breakdown energy necessary for life

metabolic rate=

rate at which ur body expends energy or burns calories

anabolism=

a set of metabolic reactions that require energy to synthesize new molecule from simples stuff (building)

catabolism=

set of destructive metabolic reactions that transforms fuels into cellular energy

3 stages where energy is extracted from food

1. Digest, absorb, transport

2. Produce metabolites (Ex: production of pyruvate, Acetyl-CoA)

3. Metabolites turned into ATP

7 Functions of chemical energy extracted from food

1. breathing

2. blood circulation

3. maintain body temp

4. O2 delivery to tissues

5. waste removal

6. synthesize new tissues

7. repair damage and wornout tissues

molecular currency=

ATP

fundamental goal of metabolism

produce ATP

Energy is stored in

phosphate bond

what occurs in cytosol

ATP-PCr, glycolysis, glycogenesis, fatty acid synthesis

what occurs in mitochondria

kreb cycle, ETC

which energy system is not considered a metabolic pathway?

ATP-PCr (simple chem reaction)

how does ATP-PCr system create energy

Phosphocreatine (PCr) split into Cr+ Pi,

Pi bind to ADP —> become ATP

epinephrine stimulates what

glycolysis

glycolysis convert a glucose into

2 pyruvate

2ATP

2NADH+ H+

how many ATP gained from using glycogen in glycolysis

3

what catalyzes pyruvate to Acetyl-CoA conversion

PDC (Pyruvate Dehydrogenase Complex)

what regulated the pyruvate to Acetyl Co-A conversion

energy status

high ATP =high energy= slow down PDC(pyruvate dehydrogenase complex) activity

high ADP =low energy= speed up PDC

aerobic energy system consists of (2)

Krebs cycle and ETC

__ can produce ATP from any macronutrients

aerobic energy system

which ATP system is preferred at rest

aerobic

Krebs cycle is important for generating:

co-Enzymes for oxidationin ETC

describe AA’s role in Krebs cycle

used to generate building molecules in the Krebs cycle, keep it going

ETC is made up of__ on __

series of complex protein channels

on inner mitochondrial membrane

when NADH and FADH2 are oxidized during ETC, whats released

H+ —> protein pumps it into inner mitochondrial space

e- —> protein pump pass it to bind O2, make H2O

how is ATP generated in ETC

build up H+ in inner mitochondrial space

pressure push it through ATP synthase protein channel,

the energy it produces made ADP and Pi to bind, creating ATP! (aka Oxidative phosphorylation)

most cells in the body extract energy from carb via 4 metabolic processes

1. glycolysis

2. pyruvate to Acetyl-CoA

3. Krebs cycle

4. ETC and Oxidative phosphorylation

4 steps of converting energy from fats

1. lipolysis (triglyceride breakdown into glycerol and fatty acids)

2. fatty acid linked to coenzyme A —> Fatty Acyl-CoA (FAC)

3. FAC + carnitine —> cross mitochondrial matrix

4. Beta oxidation (breaks FAC down into acetly-CoA —> go to Krebs cycle)

what happens to the product of lipolysis

glycerol (3C) —> pyruvate

fatty acid bind with Acetyl-CoA—> Fatty Acyl-CoA (FAC)

describe beta oxidation

depending on length of FAC:

every 2C-C break off, produce Acetyl-CoA, FADH, NADH

How is protein used in the body

not stored, but oxidized to make ATP or converted to new protein for growth and repair of body

deamination=

AA remove nitrogen component —>ammonia —> urea —> excreted

remaining carbon go to Krebs cycles

benefit of endurance training (7)

1. increase number and size of mitochondria

2. increase conc. of glycolytic enzyme

3. improve aerobic efficiency

4. improve e- delivery to ETC

5. increase muscle’s ability to oxidize lactate

6. improve heart SV and angiogenesis (new blood vessel)

7. improve capillary density and capacity to transport fatty acid from plasma to muscle cell

gluconeogenesis=

create glucose from non-carb precursors

ex:

• AA enter Krebs cycle

• pyruvate

• lactic acid in liver —> glucose

• glycerol —> glucose

main site of glucogenesis

90% liver

10%kidney

fatty acid cannot be directly converted into -__

glucose

glycogenesis=

assembles glucoses into glycogen

when is glycogenesis active

low glucose demand, increase glycogen synthase activity, restore liver and muscle glycogen store

lipogenesis=

accelerated during times of excess calorie consumption, lead to gain in fat tissu

why does lipogenesis lead to gain in fat tissue

bc excess Acetyl-CoA molecule

3 component of energy expenditure

1. resting metabolic rate (RMR)

2. Thermic effect of food

3. PA (non-exercise activity thermogenesis + PA)

ways to measure energy expenditure

1. direct/indirect calorimetry

2. doubly labelled water

3. activity monitor

4. HR monitor

5. metabolic carts

6. prediction equations

5 factors affecting energy requirements (TDEE)

age

weight

gender

height

PA

TDEE=

total daily energy expenditure