A composition of similar cells that perform a similar function

When more than one tissue are working together and performs a function

More than one organ working together to perform a function

Hereditary material found in almost all living things. It’s the code that makes living organisms what they are.

Short segments of DNA. They tell the cell what to do and what traits to express

Humans have 23 pairs. They contain all of the DNA or “code” inside of them

Controls all of the functions of the cell. Inside the nucleus are the chromosomes which hold the DNA

Any change or signal in the environment that can make an organism react in some way.

An action or change in behavior that occurs as a result of a stimulus

The condition in which an organism's internal environment is kept stable regardless of changes outside.

How things work together or respond to each other

Organs that produce an release chemicals either through tiny tubes called ducts or directly into the bloodstream

Chemicals produced by an endocrine gland

Body's method of reacting to a condition such as a threat or challenge.

Supports body; protects internal organs; allows movement

Guards against infection and injury; helps regulate body temperature

Transports oxygen & nutrients to parts of the body and remove wastes from the body

Brings in oxygen needed by the cells; removes carbon dioxide from body (breathing)

With the help of the skeletal system, produces movement