1. Levels of Organization
NGSS Unit 6
7th Grade Science

2. What do all of these pictures have in common?

3. Multicellular Organisms
In unicellular (single-celled) organisms, the single cell performs all life functions. However … multi-cellular organisms have various levels of organization.
Individual cells may perform specific functions and also work together for the good of the entire organism.
Multicellular organisms have 5 Levels of Organization from simple to complex.

4. Level 1: Cells Basic structural unit of living things
May serve a function within the organism
Examples:
blood cells, nerve cells, bone cells ,etc.

5. Level 2: Tissues
Made up of cells of similar structure and function and work together to perform a specific function.
Examples:
Blood, nervous, bone, etc.

6. Level 3: Organs
Made up of tissues that work together to perform a specific activity.
Examples:
Heart, brain, skin, etc.

7. Level 4: Organ Systems
Groups of two or more organs that work together to perform a specific activity.
Examples:
Circulatory system, digestive system, nervous system, endocrine system, etc.

8. Level 5: Organisms
Entire living things that can carry out all living processes.
Usually made up of organ systems, but an organism can be made up of only one cell such as a bacteria.
Examples:
Bacteria, mushroom, sunflower, human, etc.

9. Levels of Organization
Cells are the simplest level of organization.
However … what makes up cells?

10. Exit Slip – Writing Prompt
Complete on an blank piece of paper.
In your own words, define what a cell is. Also explain how one single cell can create a multi-cellular organism such as a human being. In your explanation, use levels of organization to support your response.
Page requirement: at least ¾ of a page