Introduction to Life

Life - the condition that distinguishes animals and

plants from inorganic matter.

Living – alive, not dead or lifeless.

Nonliving – inanimate, inactive, not endowed with

life.

These definitions do not tell us what makes

something alive!

So, what are the characteristics of life??

What makes something alive?

1. Homeostasis

2. Organization

3. Metabolism

4. Growth

5. Adaptation

6. Response to stimuli

7. Reproduction

Characteristics of Life

● Homeostasis – tendency to maintain a

stable, balanced, internal environment.

Characteristics of Life

● Organization – All things are made of one

or more cells.

Characteristics of Life

● Metabolism – must transform energy by

converting chemicals & energy into

cellular components.

Characteristics of Life

● Growth – Increase in size over time

Characteristics of Life

● Adaptation – ability to change over time

in response to the environment.

Characteristics of Life

Characteristics of Life

● Response to stimuli – will react to

environmental factors such as heat,

light, and food availability.

Characteristics of Life● Reproduction – ability to produce more

of the same type of organism.

Is it living?

1. Homeostasis?

2. Organization?

3. Metabolism?

4. Growth?

5. Adaptation?

6. Response to stimuli?

7. Reproduction?

Is it living?

Is it living?

Is it living?1. Homeostasis?

2. Organization?

3. Metabolism?

4. Growth?

5. Adaptation?

6. Response to stimuli?

7. Reproduction?

Is it living?

Is it living?1. Homeostasis?

2. Organization?

3. Metabolism?

4. Growth?

5. Adaptation?

6. Response to stimuli?

7. Reproduction?

Is it living?

Is it living?1. Homeostasis?

2. Organization?

3. Metabolism?

4. Growth?

5. Adaptation?

6. Response to stimuli?

7. Reproduction?

Okay, so now we know how

to tell if something is living

or nonliving…

How is life organized?

Organization

Cells are the basic building blocks of

living things. They contain organelles

and genetic material.

Tissues are groups

of similar cells

organized to work

together.

Examples: epithelial,

muscle, nervous,

and connective.

Organs are structures

made up of several

groups of tissues

working together to

perform a specific

function.

Examples: heart,

lungs, brain, skin,

etc.

Organ systems are groups of organs

working together to perform a function.

Examples: digestive, cardiovascular,

respiratory, and nervous systems

Organisms are living things. Some are

single-celled, others are multicellular.

Frequently they have many organ

systems working together.