Concepts Of Biology

Front 1

Entropy

Back 1

a measure of a system’s disorder

Front 2

Flow of Energy

Back 2

Organisms maintain order by being resupplied with energy
The sun is life’s primary energy source
Energy flows in one direction from more usuable to less usable forms
Heat is the least usuable form of energy

Front 3

Activation Energy

Back 3

Minimum amount of energy required to start a reaction; enzyme action lowers this energy barrier.

Front 4

Feedback Inhibition

Back 4

Of cells, an activity causes a change in cellular conditions, and that change in turn causes the activity to slow down or stop.

Front 5

Enzyme

Back 5

A type of protein (or, rarely, RNA) that accelerates a chemical reaction

Front 6

Diffusion

Back 6

The net movement of a substance down a concentration gradient

Front 7

Passive Transport

Back 7

Flow of solutes through transport proteins down gradient
Does not require any energy input

Front 8

Active Transport

Back 8

Movement of solutes up gradient
Transport protein must be activated
Uses ATP energy
Helps maintain membrane gradients (Ca+, Na+, K+) that are essential for:
Muscle contraction
Neuron function

Front 9

Osmosis

Back 9

Diffusion of water between two regions separated by a selectively permeable membrane.

Front 10

Hypertonic

Back 10

having more solutes (low water conc.)

Front 11

Isotonic

Back 11

having the same amount of solutes (same water conc.)

Front 12

Hypotonic

Back 12

having fewer solutes (high water conc.)