Unit 6 Physiology 3 Benchmark

Vanessa Yang
Smith
Period 6 Biology HP
17 March 2014
Biology Study Guide: Unit 6 Physiology III Benchmark
1. Homeostasis maintains and keeps a balance of an organism’s internal environment.
2. The body maintains homeostasis by the feedback inhibition, in which a stimulus produces a response that opposes the original stimulus.
3. The axon terminal is the nerve ending. The nodes speed up the message. The myelin sheath is an insulating membrane. The axon carries impulses away from the cell body. The cell body is the largest part of a typical neuron. The dendrites carry impulses from the environment or from other neurons toward the cell body. The nucleus is the control center of the cell.

4. A synapse is location at which a
When an impulse arrives at an axon terminal, the vesicles release the neurotransmitters into the synaptic cleft. The neurotransmitter molecules diffuse across the synaptic cleft and attach themselves to receptors on the membrane of the neighboring cell. This stimulus causes positive sodium ions to rush across the cell membrane, stimulating the second cell. If the stimulation exceeds the cell’s threshold, a new impulse begins.
7. The autonomic nervous system regulates activities that are involuntary.
8. I don’t know. I’m really tired. Maybe.
9. The hypothalamus is the brain structure that acts as a control center for recognition and analysis of hunger, thirst, fatigue, anger, and body temperature. The pons is the region in the brain stem that regulates flow of information between the brain and the rest of the body. The cerebellum is the region of the brain that coordinates body movements. The cerebrum is the area of the brain responsible for all voluntary activities of the body.
10. The skin, lungs, liver, kidneys, bladder, and large intestines are in charge of waste removal.
11. When a neuron is resting, the outside of the cell has a net positive charge, and the inside of the cell has a net negative
Sensory receptors are neurons that react to a specific stimulus such as light or sound by sending impulses to other neurons, and eventually to the central nervous system.
14. Three sensory receptors found in the skin are pain receptors, thermoreceptors, and mechanoreceptors.
15. The parathyroid glands act to maintain homeostasis of calcium levels in the blood.
16. Insulin and glucagon help to keep the level of glucose in the blood stable. Insulin stimulates cells in the liver and muscles to remove sugar from the blood and store it as glycogen or fat. Glucagon stimulates the liver to break down glycogen and release glucose back into the blood. It also stimulates the release of fatty acids from stored fats.
17. The sodium-potassium pump in the neuron cell membrane uses the energy of ATP to pump Na+ out of the cell and, at the same time to pump K+ in.
18. The sensory division of the peripheral nervous system transmits impulses from sense organs to the central nervous system. The motor division transmits impulses from the central nervous system to the muscles or glands.
19. The nerve impulses are electrical current