| A | B |
|---|
| central nervous system | Include the brain and spnal cord |
| reflex | An automatic response that happens very rapidly |
| motor neuron | A neuron that sends an inpulse to a muscle |
| sensory impulse | A neuron that picks up information from the environment and sends it to the brain. |
| axon | Part of a neuron that carries impulses away from the cell |
| synapse | The space between an axon and the next structure |
| peripheral nervous system | All the nerves that connect the CNS to all parts of the body. |
| brainstem | Controlls involuntary process such as breathing |
| target cells | A cell that interacts only with a specific hormone causing changes only in specific body organs. |
| negaive feedback | A process in which a system is turned off by the condition it produces. |
| cerebellum | Part of the brain that coordinates muscles and maintains balance |
| cerebrum | Part of the brain that carriesout complex mental processes. |
| endocrine system | Controls both daily activities and long-term changes through hormones |
| hormones | The chemical products in the endocrine system that act on the body |
| sperm | male sex cell |
| testes | Where sperm is produced |
| zygote | A fertilizated egg |
| ovulation | The process where a mature egg is released from the ovary |
| ovaries | Where eggs are produced |
| oviduct | Where human eggs are usually fertilized |
| identical twins | Produced from the same egg. |
| fraternal twins | Produced from two different eggs. |
| menstruation | The process that occurs if fertilization does not take place. |
