Topic 1.1 Characteristics of Living Organisms

MRS GREN

An acronym used to remember the characteristics of all living organisms: movement, respiration, sensitivity, growth, reproduction, excretion, and nutrition.

Movement

An action by an organism or part of an organism causing a change of position or place.

Respiration

Chemical reactions in cells that break down nutrient molecules and release energy for metabolism.

Sensitivity

The ability to detect and respond to changes in the internal or external environment.

Growth

A permanent increase in size and dry mass, achieved through cell division (mitosis) and an increase in cell size.

Reproduction

The processes that make more of the same kind of organism.

Excretion

The removal of waste products of metabolism and substances in excess of requirements.

Nutrition

The taking in of materials for energy, growth, and development.