photosynthesis and enzymes

enzyme

proteins that are biological catalysts and speed up chemical reactions

catalysts

chemical that speeds up reactions without being used up by lowering the activation energy

activation energy

energy needed to start a reaction

active site

3D shape on the surface of an enzyme that the substrate binds to

enzyme-substrate complex

enzyme with a substrate in its active site

specific

one enzyme can only catalyse one reaction

substrate

substance on which an enzyme works

lock and key model

explains that enzymes are specific with substrates

induced fit

explains that some enzymes can alter their shape to fit the substrate

optimum temperature

temperature that enzymes work best at

denaturation

permenant change in the shape of the active site caused by pH of high temperature breaking hydrogen bonds making enzyme inactive

inhibitor

poisons which bind to the substrate and change the shape of the active site causing enzyme to be inactive

cofactors

non-protein molecules that bond to enzymes making them more effective

photosynthesis

process in chloroplasts that uses light energy to produce glucose

light dependent reaction

reaction that occurs in the light of the chlorophyll of the thylakoid membranes in the chlorplast to produce H and ATP

photolysis

process where light energy is used to split H2O into 2 H’s and an O

stroma

colourless liquid that contains enzymes for light independent reactions

stomata

pores under leaf that gases and water diffuse through

pallisade cells

upright cells near the surface of the leaf that contain the most chloroplasts

limiting factors e.g.

temperature, light intensity, CO2 concentration, light wavelength

chlorophyll

green pigment found in thylakoid membranes that absorb light energy

limiting factors

factors found in least favourable amounts and causes reaction rates to plateau

granum

a stack of thylakoids in the chloroplast