Cell Theory

Cell

1 BCE

Cells are the basic structures of all living organisms. Cells provide structure for the body, take in nutrients from food and carry out important functions.

Tissue

1 BCE

Tissues are groups of cells that have a similar structure and act together to perform a specific function. There are four different types of tissues in animals: connective, muscle, nervous, and epithelial. In plants, tissues are divided into three types: vascular, ground, and epidermal. Groups of tissues make up organs in the body such as the brain and heart.

Organ

1 BCE

Groups of tissues make up organs in the body such as the brain and heart.