Biology - Cellular Energy

ATP synthase

a protein complex that uses a hydrogen ion gradient to drive forward the production of ATP

autotrophs

an organism able to build all the complex organic molecules that it requires as its own food source, using only simple inorganic compounds

Calvin cycle

the process by which carbon dioxide is reduced to carbohydrate during photosynthesis

carbon fixation

process by which carbon dioxide is converted into another organic compound by an autotroph

chemiosmosis

using energy stored in the hydrogen ion gradient to do work

chlorophyll

a pigment found commonly in plant cells that is used to convert solar energy to chemical energy

chloroplast

a cell-like organelle present in algae and plants that contains chlorophyll and carries out photosynthesis

electrochemical gradient

diffusion gradient of an ion accounting for both the concentration difference and the charge of either side

heterotrophs

an organism that cannot derive energy from photosynthesis or inorganic chemicals, and so must feed on other plants and animals, obtaining chemical energy by degrading their organic molecules

light reactions

the first stage in photosynthesis where chloroplasts are used to convert solar energy into chemical energy of ATP or NADPH

photolysis

a process in which light breaks down molecules

photon

particle of light energy

photophosphorylation

formation of ATP molecules in the chloroplast using radiant energy

photosynthesis

conversion of light energy to chemical energy which is stored in the form of carbon compounds

photosystem

an organized complex of chlorophyll, other pigments, and proteins that traps light energy as excited electrons

rubisco

an enzyme catalyzing the first step of Calvin cycle

RUBP

4 carbon compound that is used in photosynthesis to form intermediate compounds

stroma

dense fluid surrounding thylakoid membrane, where organic molecule synthesis occurs

thylakoids

sac inside chloroplast containing the molecules needed to convert light into chemical energy

wavelength

distance between the tops of waves that is used to measure light