Chapter 1Cells the Basic Units of Life

1-3

Organization of Living Things

Essential Questions/Learning Goals:

What are three advantages of being multicellular?

Describe the four levels of organization. Explain the relationship between

structure and function

Science Terms

Tissue Organ Organ system Organism Structure Function

How do multicellular organisms grow larger?

Multicellular organisms grow larger by adding more small cells rather than making their cells larger.

What are the benefits of being multicellular

Larger Size:• Larger organisms are less likely to be preyed

upon.

Multicellular Benefits Continued

Longer Life:• The lifespan of a multicellular organism is not

limited to the lifespan of any single cell in its body.

Multicellular Benefits Continued

Specialization:• Each cell in a multicellular organism has a

particular job.• Specialization makes the cell more efficient or

better suited to perform their job.

• Ex. Cardiac cells are specialized to never tire.

Cells Working Together:

Tissue:• A group of cells that work together to perform a specific

task.

• The material around and between the cells are part of that tissue.

Animals have four basic types of tissue

Muscle tissue Nerve tissue Connective tissue Protective tissue

Plants have three basic types of tissue.

Transport tissue: moves water and nutrients throughout the plant.

Protective tissue: Covers the plant, retains water.

Ground tissue: Photosynthesis occurs here.

Tissues Working Together:

Organ:• A structure that is formed of two or more tissues that

combine to perform a specific task.

• Animals: Heart, lungs, kidneys, brain, lungs, skin, liver.

• Plants: Leaves, stems, and roots.

Organs Working Together:

Organ System:• A group of organs that work together to perform a

specific function for the body.

• Animals: digestive, respiratory, circulatory, nervous.

• Plants: Stem, root, and leaf.

Organisms:

Anything that can perform all of life’s processes by itself.

Unicellular Organisms

Single celled organisms.• Although these organisms have only one cell, they can

form colonies that can be very large

Single celled organisms.

Multicellular Organisms

Organisms with two or more cells.• Cells are specialized to perform specific

functions.

Structure and Function:

Structure is…• the arrangement of parts in an organism

• Its shape and what its made of.

Function is the…• job that the structure performs.

The structure and function of organs and tissues allows them to perform their function.