All living things, including plants, animals, and humans, are made of cells. Cells are the smallest unit of life and come in different types, like skin cells, muscle cells, and plant cells. Cells perform important functions like obtaining nutrients, removing waste, and reproducing to make new cells. The cell theory states that all living things are composed of cells, cells are the basic unit of life, and new cells are produced from existing cells.

1. What do plants, animals and
people have in common?

2. Chapter 2
Lesson 1: Cells (p. 31)
 This is your skin.
 It is made up of cells.
 Cells are the smallest
unit of life.

3.  Cells are very small
 We use a microscope to see them.
 Hooke made the first microscope
and discovered the cell.

4.  Small organisms are made up of one cell (uni-cellular).
 Big organisms are made up of millions of cells (multi-cellular).

5. Jobs of a cell:
 Obtain nutrients and energy needed for the body.
 Removes wastes
 Grow and reproduce to give new cells.
 Muscle cells helps in moving your body.
 Skin cells help in protecting your body.

6. Plant cells absorb sunlight energy to produce their own
food.

7. Cell Theory:
1. All living things are made of one or more cells.
2. Cells are the basic unit of life.
3. All cells come from other living cells.