System

a group of things that affect each other and function as a whole

Example: the nervous system and the skeletal system

Function

what something does

Example: the function of muscle is to move bones

Structure

the specific form and shape of something

Example: the skeleton is a structure in a human body

Dissect

to take something apart to study it

Model

a pretend version of something that scientists use when the real thing is too big, small, or complicated to work with

Muscle

a part of the body that attaches to bones and allows the body to move

Joint

a part of the body where two bones come together and can bend

Bicep

a large muscle in the upper arm

Tendon

a part of the body that attaches muscle to bone

Skeleton

all of the bones of an animal, including humans

Bones

the hard parts inside many animals that help give their bodies shape

Pupil

the dark opening in the center of the eye

Iris

the colored part of the eye that is shaped like a donut

Cornea

the clear layer in front of the eye

Retina

the back of the eye that senses light and sends messages to the brain

Lens

a clear object that changes the direction of light as it passes through

Nocturnal

active mostly at night

Brain

a part of the body that receives, processes, and responds to signals from the nerves

Nerves

The parts of the body that carry signals from one part of the body to another

Nervous System

the brain and all the nerves in the body