Cells: The Basic Units of Life 3-1 Organization of Life

Cells are the lowest level of organization of an organism.

Cells are said to be the basic or primary level of organization

Cells are the smallest unit that can perform all the processes necessary for life.

The first cell of a chicken is one of the largest cells in the world.

An ostrich egg is the largest single cell in the world.

Why did the chicken cross the playground?

To get to the other slide!

Tissue is made up of cells that are like each other and do the same job.

A group of cells with the same function make up tissue

An organ is a structure made up of two or more tissues working together.

A group of organs that work together form an organ system which is the highest level of organization.

An organ system is made up of two or more organs.

Skin is the body’s largest organ.

Organization of Life Cells→Tissue→Organs→System→Organism cell, tissue, organ, system, organism

Characteristics of multicellular organisms Larger size Longer life More - specialized cells

Unicellular organisms are made up of a single cell

Humans like you are multicellular organisms

Even a simple multicellular organism can have specialized cells.

The Big Picture

A group of organisms that are of the same kind and that live in the same area make up a population