Maintenance of Life

Requirements of Organisms

Requirements of Organisms

Being alive requires certain environmental factors, including the following:

Requirements of Organisms

• Water

• Foods

• Oxygen

• Heat
  

• Pressure

Water

Water is the most abundant chemical in the body.
Required for many metabolic processes and provides the environment in which most of them take place.
Carries substances within the organism.
Important in regulating temperature.
Inside cells, water constitutes intracellular fluid and outside cells, extracellular fluid

Foods

• Provide body with chemicals (nutrients).

• Some used as energy sources; 

• Others supply raw materials for building new living matter;

• Others help regulate vital chemical reactions.

Oxygen

Release energy from food substances - this energy drives metabolic processes.

Heat

• Form of energy.

• Product of metabolic reactions.

• Degree of heat present partly determines the rate at which reactions occur.

Pressure

Application of force to something.

Atmospheric pressure - Important in breathing.

Hydrostatic pressure - Important in blood pressure

Open Ended

Name the 5 requirements for life: