y5 bio: cluster 4 (cell respiration)

ATP is formed by…

3 phosphate groups, 1 ribose sugar, 1 adenine base

ATP’s 3 characteristics

cannot cross membranes (prevent energy leakage and requires transporters), water soluble due to phosphate groups (easier transport), chemically stable at neutral pH

what is ATP generated from?

ADP and inorganic phosphate

what life processes DOESNT require ATP?

simple/facilitated diffusion, osmosis and hydrolysis

condensation reaction equation regarding ADP and ATP

ADP + phosphate + energy = ATP + H2O

hydrolysis reaction equation regarding ADP and ATP

ATP + H2O = ADP + phosphate + energy

which of the 2 reactions (condensation and hydrolysis) requires and releases energy? and where does this energy come from?

condensation requires energy that comes from food oxidation, hydrolysis releases energy that powers most cellular processes

what are the 4 cellular respiration processes?

glycolysis, link reaction, krebs cycle and oxidative phosphorylation

cell respiration VS gas exchange VS ventilation (definition)?

cell respiration (occurs inside cells), gas exchange (swapping gases at respiratory surface), ventilation (like breathing)

aerobic VS anaerobic respiration (substrates and waste products)

aerobic:

substrates - sugars/lipids

waste - CO2 + H2O

anaerobic:

substrates - glucose

waste- lactate

aerobic VS anaerobic respiration (location)

cytoplasm and mitochondria (aerobic), cytoplasm (anaerobic)

does aerobic or anaerobic respiration produce more ATP?

aerobic, with 30-32 units of ATP yield, compared to anaerobic, with 2 units of ATP yield

what can we use to measure respiration rate?

1. respirometer, through quantifying the oxygen consumption

2. capillary manometer to measure carbon dioxide production and O2 uptake by pressure change

3. pH meter to measure CO2 production rate

what’s the special solution in respirometer to absorb CO2?

KOH or NaOH

what factor must be controlled when using respirometer?

temperature must be controlled, as respiration is enzyme dependent and affected by temp

what are the variables affecting respiration rate?

temp, substrate concentration and oxygen availability

how does NAD act as a hydrogen carrier?

it accepts 2 hydrogen atoms and is reduced to form NADH

reaction equation of NAD being reduced

NAD+ + 2H -> NADH + H-

what are the 4 main stages WITHIN glycolysis?

phosphorylation, lysis, oxidation, ATP formation

do YOU know the glycolysis stages…? imagine the whole diagram in your head now…

just a recap, 4 stages are: phosphorylation, lysis, oxidation and ATP formation

after glycolysis, if oxygen is lacking and link reaction cannot occur, the 2 pyruvate molecules form…

2 lactate molecules through anaerobic respiration in some bacteria and animal cells

regarding pyruvate forming lactate in human pathway, what does ethanol pathway in yeast fermentation look like?

instead of lactate, 2 pyruvate forms 2 acetaldehyde molecules + 2CO2, then forms 2 ethanol molecules