Unit 2 Part I Review
Across
- 3. he neuron extension that passes messages through its branches to other neurons or to muscles or glands
- 5. the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms
- 6. the subfield of biology that studies the molecular structure and function of genes
- 9. a neuron’s reaction of either firing (with a full-strength response) or not firing.
- 13. every nongenetic influence, from prenatal nutrition to the people and things around us
- 15. “above” or “in addition to” (epi) genetics; the study of environmental influences on gene expression that occur without a DNA change
- 16. chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.
- 17. the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)
- 18. the division of the autonomic nervous system that arouses the body, mobilizing its energy
- 20. bundled axons that form neural cables connecting the CNS with muscles, glands, and sense organs
- 21. a nerve cell; the basic building block of the nervous system
- 24. the part of a neuron that contains the nucleus; the cell’s life-support center
- 27. the brain and spinal cord; the body’s decision maker
- 28. the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.
- 29. the study of how the structure and function of genes interact with our environment to influence behavior
- 32. neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
- 33. the level of stimulation required to trigger a neural impulse
- 34. cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory
- 35. the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
- 37. neurons that carry incoming information from the body’s tissues and sensory receptors to the brain and spinal cord
- 38. the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream.
- 39. the division of the autonomic nervous system that calms the body, conserving its energy
Down
- 1. the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body
- 2. the proportion of variation among individuals in a group that we can attribute to genes. The heritability of a trait may vary, depending on the range of populations and environments studied
- 3. a neural impulse; a brief electrical charge that travels down an axon
- 4. the study of the relative power and limits of genetic and environmental influences on behavior
- 7. in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state
- 8. the division of the peripheral nervous system that controls the body’s skeletal muscles
- 10. the genetic transfer of characteristics from parents to offspring
- 11. a complex molecule containing the genetic information that makes up the chromosomes
- 12. the endocrine system’s most influential gland. Under the influence of the hypothalamus, this gland regulates growth and controls other endocrine glands.
- 14. neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs
- 19. threadlike structures made of DNA molecules that contain the genes
- 22. a simple, automatic response to a sensory stimulus, such as the knee-jerk response
- 23. the biochemical units of heredity that make up the chromosomes; segments of DNA capable of synthesizing proteins
- 25. the complete instructions for making an organism; consisting of all the genetic material in that organism’s chromosomes
- 26. a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress
- 30. a neurotransmitter’s reabsorption by the sending neuron.
- 31. chemical messengers that cross the synaptic gaps between neurons, influencing whether that neuron will generate a neural impulse
- 32. a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next
- 36. a neuron’s often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body