cell processes

Active Site

A specific shaped part of an enzyme where the substrate binds.

Active Transport

The movement of molecules from an area of low concentration to an area of high which requires energy.

Aerobic respiration

Respiration in the presence of oxygen.

Anabolic enzyme

An enzyme that takes small molecules and joins them together.

Anaerobic respiration

Respiration with limited oxygen.

Catabolic enzyme

An enzyme which takes large molecules and breaks them up.

Cell Wall

Rigid layer of cells found only in plants.

Chlorophyll

Pigment found in plants which gives the plant its green colour.

Chloroplast

Site of photosynthesis.

Cristae

Part of mitochondria (the folds) where the electron transfer chain occurs.

Denature

The changing in the shape of the active site of an enzyme, so the substrate can no longer fit - caused by high temperatures and incorrect pH.

Diffusion

The movement of materials from an area of high concentration to an area of low concentration.

DNA replication

The copying of DNA before the cell divides

Enzymes

Biological catalysts which speed up biochemical reactions in an organism.

Facilitated diffusion

A form of passive transport where molecules move across the cell membrane through the membrane proteins

Flaccid

A cell that is limp and floppy

G1 of cell cycle

The stage in the cell cycle where the cell grows and does its job.

G2 of cell cycle

The stage in the cell cycle where the replicated chromosomes are checked for mistakes.

Golgi body

Part of cell where proteins are modified and packaged.

Grana

Part of chloroplast where the light stage occurs

Hypertonic solution

A solution with a high concentration of solute, therefore a low concentration of water

Hypotonic solution

A solution with a low concentration of solute, therefore a high concentration of water

Induced fit model

The enzyme model where the enzyme changes its shape after bonding with the substrate

Inhibitors

poisons that bind to the active site of enzymes and stop them working

Isotonic solution

A solution which has the same osmolarity or solute concentration as another solution

Lock and key model

The model explaining how enzymes work where the enzyme is a rigid structure

Matrix

Part of the mitochondria where the citric acid cycle occurs

Mitochondria

Organelle in cell where respiration occurs

Mitosis

The stage of the cell cycle where the replicated chromosome is split into 2 cells

Osmosis

The net movement of water through a semi-permeable membrane from an area of high concentration to an area of low concentration

Palisade layer

Part of the leaf where most chloroplasts are found, so most photosynthesis occurs here

Passive transport

The movement of molecules from an area of high concentration to an area of low concentration which doesn't require energy

Phagocytosis

A form of active transport by which a cell uses its plasma membrane to engulf a large solid particle

Pinocytosis

A form of active transport where fluids and nutrients are ingested by cells

Ribosomes

Part of cell where protein synthesis occurs

S stage of cell cycle

The stage in the cell cycle where the DNA is replicated

Semi permeabe membrane

A membrane that allows some substances to pass through it but not others

Stroma

Part of chloroplast where the dark stage occurs

Turgid

A cell that is it is swollen, bloated, puffed up or inflated

Endocytosis

Endocytosis is the process where a cell takes in large molecules or particles from outside the cell by engulfing them with its plasma membrane.

Exocytosis

Exocytosis is an active transport process where a cell moves large substances, waste products, or secretory molecules out of the cell