Aim: What are the characteristics of living things?

Topic: Conditions for life

What is BIOLOGY?

- the study of life.

What is an ORGANISM?

- any living thing.

What is an Environment?

- the surroundings of an organism which affects how it lives.

What do all organisms need to survive?

CONDITIONS/FACTORS FOR LIFE:CONDITIONS/FACTORS FOR LIFE:

1. SOURCE OF ENERGY

- needed for life processes.

- light, FOOD

**The SUNSUN is the origin of almost all the energy available to all living things.

2.2. WATERWATER

- water makes up more than 65% of all organisms.

- it dissolves & carries materials throughout an org.

- many chemical reactions take place in water.

- helps keep an organisms temperature stable.

3. GASES- found in the environment.- needed to perform life processes.- oxygen (O2), carbon dioxide (CO2) &

nitrogen (N).4. PROPER TEMPERATURE- needed to maintain “homeostasishomeostasis” or

“dynamic equilibrium” which means to have a constant, stable internal environment.

5. PROPER HABITAT

- a place to live and find all the other factors needed for to carry out the life processes.

What are the life processes?What are the life processes?

- processes that all living things must do in order to survive. THEY ARE:

1. METABOLISM

2. RESPONSE

3. GROWTH

4. MOVEMENT

5. REPRODUCTION

What is METABOLISM??1. Metabolism = total of all the

chemical activities that occur in a living thing involving energy usage.e.g. Building substances.

Breaking down substances.- in order for these chemical

reactions to take place, organisms must take in food for energy.

What is RESPONSE??What is RESPONSE??

-a reaction to a stimulus.What is a stimulus?

-any change in the internal or external environment of an organism (temperature, weather, light, predator).

e.g. blink, leaves fall off a tree, leaves bend towards light

What is Homeostasis?

• Homeostasis is the body’s ability to maintain a constant internal environment.

• Examples include:– Maintenance of body temperature.– Maintenance of pH.– Maintenance of sugar level in the blood.– Maintenance of water level in the body.

• Failure to maintain homeostasis will result in the organism becoming sick or dying!

What is GROWTH?- building new parts for an organism

during metabolism.- an increase in cell size.- replace or repair of dying or dead

cells.- maturation

e.g. a baby getting bigger, fruit ripening

What is MOVEMENT?

- a change in position.

- a whole organism can move.

- internal organs, fluid, blood can move.

- cell parts and cells can move.

What is REPRODUCTION?

- production of a new offspring or organism.

2 types: 1) sexual – 2 parents

2) asexual – 1 parent

** NOT needed for the individual organism to survive – just the species.

Summary:

All forms of life share certain characteristics. Living things are able to move, perform complex chemical activities, grow, reproduce, and respond to stimuli.