AP Bio Unit 3 Test (enzymes, cellular respiration, photosynthesis)

what is an autotroh?

organism that can produce its own food

what is a heterotroph?

organism that "consume" other organisms

what is the site of the light reaction of photosynthesis?

thylakoid

Primary purpose of thylakoid:

to help make ATP and NADPH

Three parts of a chloroplast:

thylakoid, grana, stroma

Grana:

stack of thylakoids - create more surface area

Site of the light-independent photosynthesis reaction:

stroma

primary purpose of the stroma:

to use the ATP and NADPH to make SUGAR using CO2

Calvin Cycle makes.... using.....

makes sugar using CO2 and energy

What is carbon fixation?

incorporating CO2 into organic molecules

first step in photosynthesis:

sunlight is converted it into ATP and NADPH

second step in photosynthesis:

takes the chemical energy (ATP and NADPH) and uses that energy to power the production of sugar (this is the light-independent reaction)

What does the energy of sunlight directly do?

splits H2O

what is a photosystem?

group of light absorbing pigments in thylakoid membrane

What is Photosystem I responsible for?

ATP and NADPH production

What is photosystem II responsible for?

ONLY ATP production

First step of Light-dependent photosynthesis reaction:

1. H2O splits to O2 gas , hydrogens moves through PSII forming a hydrogen gradient

Second step of light-dependent photosynthesis reaction:

electrons from the water move through PSI

third step of light-dependent photosynthesis reaction:

electrons from water bond with NADP+ to make NADPH

last step of light-dependent photosynthesis reaction:

hydrogen gradient forms, hydrogen moves through ATP synthase to turn ADP into ATP

First step of light-independent reaction of photosynthesis:

ATP and NADPH is used to power the fixing of CO2 into sugar

second step of the light-independent reaction of photosynthesis:

CO2 is used to make carbohydrates (sugar)

other name for light independent reaction?

Calvin Cycle

What does ATP add to Calvin Cycle?

energy

What does NADPH add to Calvin Cycle?

high energy electrons

carbon fixation in Calvin Cycle:

catalyzed by the enzyme RUBISCO -- captures CO2 from atmosphere -- captures carbon and turns it into sugar

what powers ATP synthase?

hydrogen

Photosynthesis equation:

CO2 + H2O + light energy = sugar + oxygen

catabolic reactions:

breakdown of molecules for energy

anabolic reaction:

use energy to BUILD molecules

what is a substrate?

a molecule acted upon by an enzyme

what is the active site?

site at which the enzyme binds to the substrate

what is the enzyme substrate complex?

temporary molecule formed when an enzyme comes in perfect contact with its substrate

what is induced fit?

when the enzyme changes to fit around the substrate

what are enzymes?

catalytic proteins

factors that affect enzyme function?

pH, high temperatures, salts

what is a coenzyme?

organic non-protein that bonds with an enzyme to catalyze a reaction

what is a cofactor?

a non-protein chemical that assists with biological chemical reactions

allosteric activation:

protein binds to the enzyme in order for the protein to function

allosteric inhibition:

regulatory protein bonds to the enzyme in the inactive form (no products made, enzyme does not work)

feedback inhibition:

end product shuts down the pathway

Chemiosmosis

diffusion of H ions across the membrane via the ATP synthase

cellular respiration equation:

glucose + oxygen --> carbon dioxide + water + energy (in the form of ATP)

Where does cellular respiration occur?

mitochondria

2 main pathways of cellular respiration:

anaerobic and aerobic

what is anaerobic respiration?

Occurs in the absence of oxygen

two types of anaerobic respiration:

lactic acid fermentation and alcoholic fermentation

what is aerobic respiration?

Respiration with oxygen

3 steps of aerobic cellular respiration:

1. glycolysis 2. Krebs Cycle 3. Electron transport chain

where does glycolysis take place?

cytosol

what happens in glycolysis?

energy from glucose is released, forms ATP, NADH, and pyruvate (from glucose)

Where does the Krebs cycle occur?

matrix of mitochondria

What happens in the Krebs Cycle?

pyruvate moves from the cytosol to mito. matrix

What does the Krebs cycle produce?

carbon dioxide, ATP, NADH, FADH2

what is the function of the Krebs Cycle?

to produce electron receptors for the ETC

What is the waste product of the Krebs cycle?

CO2

where does ETC take place?

inner membrane of mitochondria

where is the most ATP made in cellular respiration?

ETC

what does the ETC form?

- protein hydrogen gradient established along thylakoid membrane that powers ATP synthase

- ATP synthase creates ATP via chemiosis

- electrons fromFADH2 + NADH that pass through the membrane to O2, as these electrons pass through, a protein gradient is established in the membrane space

What is formed at the end of ETC?

ATP and H2O

What goes into the ETC?

NADH, FADH2, O2 (oxygen comes from the atmosphere)

Where does fermentation occur?

cytosol

when is glucose not being used to its full potential?

fermentation

waste products of fermentation:

alcohol or lactic acid