| A | B |
|---|
| cartilage | thick smooth, flexible and slippery tissue that covers the end of bones, makes movement easier by reducing friction and absorbing shocks |
| central nervous system | made up of the brain and spinal cord |
| dermis | skin layer below the epidermis that contains blood vessels, nerves, oil, sweat glands and other structues |
| epidermis | outer, thinnest skin layer that constantly produces new cells to replace the dead cells that are rubbed off its surface |
| involuntary muscle | muscle, such as heart muscle, that cannot be consciously controlled |
| joint | any place where two or more bones come together; can be movable or immovable |
| ligament | tough band of tissue that holds bones together at joints |
| melanin | pigment produced by the epidermis that protects skin and gives skin and eyes their color |
| neuron | basic functioning unit of the nervous system, made up of a cell body, dendrites and axons |
| periosteum | tough, tight fitting membrane that covers a bone's surface and contains blood vessels that transport nutrients into the bone |
| peripheral nervous system | includes all the nerves outside the CNS; connects the brain and spinal cord to other body parts |
| synapse | small space across which an impulse moves from a axon to the dendrites or cell body of another neuron |
| tendon | thick band of tissue that attaches bones to muscles |
| voluntary muscle | muscle that can be consciously controlled |
