booster bio vids CELLULAR RESPIRATION

what is cellular respiration (of glucose) and the three ways to do it?

breaks down comps to make ATP

1) glycolysis (cytosol)

2) krebs (CAC) (mitoch matrix)

3) ETC (inner mitoch membrane)

eqn fr breakdown of glucose

gluxose + O2 —> 6CO2 + 6H2O + Energy (heat + ATP)

exergonic rxn (favorable)

substrate-level phosphorylation vs oxidative phosphorylation

Substrate level phosphorylation = makes ATP from ADP (via phosphate group transfer) (glycolysis, Krebs)

oxidative phosphorylation = ETC makes ATP

glycolysis basic summary

• takes glucose and makes 2 pyruvate, net 2ATP, + 2NADH

• PFK is the rate limiting step

role of NADH and PFK in glycolysis?

NADH = electron carrier

PFK = regulates glycolysis (irreversible —> COMMITS to glycolysis)

(if theres tons of ATP then PFK will prevent glycolysis)

when will PFL prevent glycolysis

when theres incrs of ATP

pyruvate decarboxylation

2 pyruvate gets converted to 2 Acetyl CoA (this happens twice bc theres 2 pyruvate)

which 2 pathways use substrate level phosphorylation to make ATP?

glycolysis + CAC

purpose of CAC (Kreb’s cycle)

make ATP via substrate level phosphoryaltion (in mitoch matrix) AND make 6 NADH + 2 FADH2 for ETC (they are e- carriers)

diff betwen NAD+ , FAD and NADH , FADH2

NAD + and FAD are the e- shuttles that carry NADH and FADH2 (which are the e-carrier paychecks for more charged batteries)

final electron acceptor in the ETC

Oxygen

how ATP made in ETC?

(by oxidative phosphorylation)

NADH + FADH2 gets used to make proton gradient (proton motive force) which causes ATP synthase to activate which causes chemiosmosis to make ATP which will fuel endergonic rxns

(ATP synthase = ADP to ATP)

how much ATP at the end of cellular respiration ?

34 ATP

(36 in euks)

chemiosmosis

ions moving down their gradient (not against)

benefit of cristae in cellular respiration?

cristae incrs SA = incrs ETC = incr ATP synthase = incr ATP

anaerobic respiration 2 types?

Fermentation

• alcohol fermentation (yeast/bacteria)

Lactic Acid (muscle, fungi)

fermentation vs Lactic Acid

fermentation has NO CAC or ETC.. only glycolysis

• NADH —> NAD+ (important for incr glycolysis)

• in alcohol fermentation -pyruvate —> acetylide + NADH —> Ethanol + NAD +

Lactic acid 0→ pyruvate + NADH —> Lactate + NAD+ (lactate goes to liver )

purpose of fermentation + lactic Acid (anaerobic respiration in general)

to make NAD+ for more glycolysis to occur !!

how much ATP does proks make in Aerobic Respiration?

38 ATP

(more than euks which make 36 ATP)

alternative energy sources when there is no glucose?

lipids, proteins, other carbs

2 ways carbs used as an alt energy source?

Carb metabolism = from pancreas

1) insulin —> incr glucose= glycogenesis

• makes glycogen and uses glucose for energy (glycolysis) (store for later)

2) glucagon —> decr glucose

• inhibits glycogenesis + glycolysis in less imp organs

whats the intermediate that is involved/linked in glycolysis, glycogensis, gluconeogenesis, & glycogenolysis?

GLUCOSE-6-PHOSPHATE !!!!!!!!

diffs bw:

• glycolysis

• glycogenesis

• gluconeogenesis

• glycogenolysis

• glycolysis = breakdown glucose to make pyruvate

• glycogenesis = make glycogen from glucose

• gluconeogenesis = make glucose from noncarbs (proteins + lipids) —> for liver and kidney

• glycogenolysis = break down stored glycogen

how are lipids used as an alternate energy source?

we digest triglycerides (+ cholesterol but thats not imp)

• lipase splits triglyceride into glycerol + fatty acids

  • glycerol phorphoried into —> G3P

  • fatty acids —> B-oxidation

    • makes Acetyl CoA which makes NADH + FADH = more ATP in ETC

    • so the longer the fatty acids, the more ATPs!!!!!!!!!!

what is ketone metabolism

brain likes glucose. no glucose? brain sad. so brain break down ketone to enjoy instead. heart does same thing.

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(the ketones come from fatty acids in liver)

out of the alt energy sources, which one is preferred first? and which one ISNT preferred?

carbs preferred bc it’s more accessible to ur body

proteins NOT preferred

are nucleic acids used as alt energy source?

NO , they get broken down into parts to be reused