What are the life What are the life processes by which processes by which the life of an the life of an organism is organism is maintained?maintained?

Life functionsLife functions

NutritionNutritionthe taking materials from the external the taking materials from the external

environment and changing them environment and changing them into useful forms (nutrients).into useful forms (nutrients).

2 types of nutrition:2 types of nutrition: AutotrophicAutotrophic HeterotrophicHeterotrophic

Autotrophic Nutrition:Autotrophic Nutrition: organisms make their own nutrients: organisms make their own nutrients:

photosynthesisphotosynthesis COCO22 + water + Solar energy Sugar + + water + Solar energy Sugar +

OO22

Heterotrophic nutritionHeterotrophic nutritionOrganisms cannot make their own nutrients Organisms cannot make their own nutrients

and must find them in their environment. and must find them in their environment. Processes involved:Processes involved:

1.1. Ingestion: taking in foodIngestion: taking in food2.2. Digestion: breaking down foodDigestion: breaking down food3.3. Egestion: elimination of indigestible foodEgestion: elimination of indigestible food

2. Transport2. Transport the ability to move materials into, the ability to move materials into,

out of and throughout an organismout of and throughout an organism Involves absorption (taking in) and Involves absorption (taking in) and

distribution (circulation) of nutrients.distribution (circulation) of nutrients.

3. Respiration3. Respiration

the ability to convert food into energy the ability to convert food into energy Sugar + OSugar + O22 CO CO22 + H + H22O + EnergyO + Energy

4. Excretion4. Excretion Removal of wastes from chemical Removal of wastes from chemical

reactions: (Carbon Dioxide,Water & reactions: (Carbon Dioxide,Water & Urea) Urea)

5. Growth5. GrowthThe ability to increase in sizeThe ability to increase in size Unicellular organisms: cell Unicellular organisms: cell

increases sizeincreases size Multicellular organisms: the Multicellular organisms: the

number of cells increases.number of cells increases.

6. Reproduction6. Reproduction

When an organism produces new When an organism produces new organisms of its own kind. organisms of its own kind.

1. Sexual Reproduction: 2 parents, 1. Sexual Reproduction: 2 parents, offspring not identical to either offspring not identical to either parent. Results in variation.parent. Results in variation.

2. 2. Asexual Reproduction: one parent. Asexual Reproduction: one parent. Offspring identical to the parentOffspring identical to the parent

MetabolismMetabolism is the sum total of is the sum total of ALLALL chemical reactions occurring in an chemical reactions occurring in an organism to maintain life.organism to maintain life.

HomeostasisHomeostasis is the ability to maintain a is the ability to maintain a balanced, steady-state, internal balanced, steady-state, internal environment within an organism.environment within an organism.Failure to maintain homeostasis leads to Failure to maintain homeostasis leads to illness, disease or even death.illness, disease or even death.