CHARACTERISTICS OF LIVINGTHINGS

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Characteristics Of Living Organisms

In order to identify living organisms, scientists listed 8 characteristics which all living organisms have:


1. Nutrition:

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


2. Excretion:

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


3. Respiration:

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


4. Sensitivity/Irritability

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


5. Reproduction:

Progresses that existing organisms  make more of the same kind of organism.

6. Growth and Development

The permanent increase in size and dry mass by an increase in number of cells, cell size, or both; Physical and chemical modifications in organisms that improves ability to function.


7. Movement:

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

8. Gaseous Exchange.
Entry and exit of gases across an organisms surface. Gases are needed for photosynthesis and respiration.

The 8 characteristics could be memorized by the term “Mrs. Greng”:


Movement
Respiration
Sensitivity
Growth
Reproduction
Excretion
Nutrition
Gaseous Exchange
 


Definitions:

Metabolism:
Chemical reactions taking place in cells.

Stimuli:
Changes in the environment which organisms response to.

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