B1.1 – Characteristics of Living Organisms

The first point in this section is core, and the second is supplement, which is why they seem to be the same point written twice.

Movement as an action by an organism causing a change of position or place
Respiration as the chemical reactions in cells that break down nutrient molecules and release energy
Sensitivity as the ability to detect and respond to changes in the environment
Growth as a permanent increase in size
Reproduction as the processes that make more of the same kind of organism
Excretion as removal from organisms of toxic materials and substances in excess of requirements
Nutrition as taking in of materials for energy, growth and development.

It is essential that you learn each of these definitions.

An easy way to remember all the characteristics is MRS GREN:

M – Movement

R – Respiration

S – Sensitivity

G – Growth

R – Reproduction

E – Excretion

N – Nutrition

Movement as an action by an organism or part of an organism causing a change of position or place
Respiration as the chemical reactions in cells that break down nutrient molecules and release energy for metabolism
Sensitivity as the ability to detect or sense stimuli in the internal or external environment and to make appropriate responses
Growth as a permanent increase in cell number or size or both
Excretion as removal from organisms of the waste products of metabolism (chemical reactions in cells including respiration), toxic materials, and substances in excess of requirements
Nutrition as taking in of minerals for energy, growth and development; plants require light, carbon dioxide, water and ions; animals need organic compounds and ions and usually need water

Learn these definitions!!!

If you skipped over the first point, I’m just gonna say it again: