Biology ch5

Energy

The ability to cause change or do work

Kinetic energy

Energy of motion

Potential energy

Stored energy based on position or structure

Conservation of energy

Energy cannot be created or destroyed, only changed

Chemical energy

Energy stored in chemical bonds

Enzyme

A protein that speeds up chemical reactions

Substrate

The molecule an enzyme acts on

Active site

Region of an enzyme where the substrate binds

Induced fit

When an enzyme changes shape to fit the substrate

Catalyst

Speeds up reactions without being used up

Enzyme inhibitor

A substance that decreases enzyme activity

Competitive inhibitor

Competes with the substrate for the active site

Noncompetitive inhibitor

Changes enzyme shape so substrate cannot bind

Diffusion

Movement from high to low concentration

Passive transport

Movement across membrane without energy

Facilitated diffusion

Passive transport using proteins

Selectively permeable membrane

Allows some substances to pass

Osmosis

Diffusion of water across a membrane

Hypotonic

Lower solute concentration than the cell

Hypertonic

Higher solute concentration than the cell

Isotonic

Equal solute concentration

Turgid

Firm plant cell

Flaccid

Limp plant cell

Plasmolysis

Plant cell membrane pulls away from wall

Lysis

Animal cell bursts from water intake