Cellular Energy – Vocabulary

Photosynthesis

Process that converts light energy into chemical energy stored in glucose

Cellular respiration

Process that breaks down glucose to make ATP

Chloroplast

Organelle where photosynthesis occurs

Thylakoid

Membrane sacs where light-dependent reactions occur

Grana

Stacks of thylakoids

Stroma

Fluid-filled space where the Calvin cycle occurs

Chlorophyll

Green pigment that absorbs light energy

Stomata

Leaf openings that allow CO2 in and O2 out

Mitochondria

Organelle where aerobic respiration occurs

Matrix

Inner space of mitochondria where Krebs cycle occurs

Cristae

Folds of inner mitochondrial membrane

Glycolysis

First stage of respiration that splits glucose

Pyruvate

3-carbon molecule produced by glycolysis

Acetyl-CoA

Molecule formed from pyruvate before Krebs cycle

Krebs cycle

Second stage of respiration that releases CO2

Electron transport chain

Series of proteins that pass electrons

Chemiosmosis

Movement of H+ ions through ATP synthase

ATP synthase

Enzyme that produces ATP using H+ gradient

ATP

Energy currency of the cell

ADP

Lower-energy form of ATP

NAD+

Electron carrier that becomes NADH

NADH

Electron carrier that donates electrons to ETC

FAD

Electron carrier that becomes FADH2

FADH2

Electron carrier used in ETC

NADP+

Electron carrier in photosynthesis

NADPH

Electron carrier used in Calvin cycle

Calvin cycle

Light-independent reactions that build glucose

Fermentation

Process that regenerates NAD+ without oxygen

Lactic acid fermentation

Fermentation used by muscle cells

Alcoholic fermentation

Fermentation used by yeast and plants

Aerobic respiration

Respiration that requires oxygen

Anaerobic respiration

Respiration without oxygen

Carbon cycle

Movement of carbon through ecosystems

Carbon reservoir

Place where carbon is stored

Carbon flux

Movement of carbon between reservoirs

Producers

Organisms that make their own food

Consumers

Organisms that eat other organisms

Trophic level

Feeding position in a food chain

Biomass

Total mass of living material

Energy pyramid

Diagram showing energy loss between trophic levels

Greenhouse gases

Gases that trap heat in the atmosphere