Section 1: The nature and variety of living organisms

a) Characteristics of living organisms

b) Variety of living organisms

a) Characteristics of living organisms             

1.1 recall that living organisms share the following basic characteristics:

           they require nutrition

           they respire

           they excrete their waste

           they respond to their surroundings

           they move

           they control their internal conditions

           they reproduce

           they grow and develop

 

Nutrition: Taking in nutrients which are organic substances and mineral ions, containing raw materials and energy for growth and tissue repair, absorbing and assimilating them.

 

Excretion: Removal from organisms of toxic materials, the waste products of metabolism and substances in excess.

 

Respiration: Chemical reactions that break down nutrient molecules in living cells to release energy.

 

Sensitivity: The ability to detect or sense changes in the environment and to make responses.

 

Reproduction: Progresses that make more of the same kind of organism.

 

Growth: The permanent increase in size and dry mass by an increase in number of cells, cell size, or both.

 

Movement: An action by an organism or part of an organism that changes position or place.

 

The seven characteristics could be memorized by the term “Mrs. Gren”:

Movement

Respiration

Sensitivity

Growth

Reproduction

Excretion

Nutrition