19. An axon is A) B) C) D) a cell that serves as the basic building block of the nervous system. the cell's life-support center. a molecule that blocks neurotransmitter receptor sites. the extension of a neuron that carries messages away from the cell body. 20. Information travels through axons that are bundled into the "cables" that we call A) interneurons. B) action potentials. C) nerves. D) association areas The two divisions of the peripheral nervous system are the A) B) C) D) 21. brain and spinal cord. cerebrum and cerebellum. limbic system and endocrine system. somatic nervous system and the autonomic nervous system. REM sleep is called paradoxical sleep because A) our heart rate is slow and steady, while our breathing is highly irregular B) we are deeply asleep but can be awakened easily C) our nervous system is highly active, while our voluntary muscles hardly move. D) it leads to very creative dreams that are perceived as colorless images 22. The human sleep cyele repeats itself about every A) 30 minutes. B) 90 minutes C) 2 1/2 hours. D) 4 hours 23. Sleep deprivation has been shown to A) 24. B) C) D) increase attentiveness to highly motivating tasks. reduce high blood pressure. diminish immunity to disease. increase sleep apnea. During a heated argument with his teenage daughter, Mr. Reid suddenly lapsed into a state of REM sleep. Mr. Reid apparently suffers from A) narcolepsy B) insomnia. C) sleep apnea. D) REM rebound. 25.
19) An axon is an extension of a neuron that carries messages
away from the cell body. An axon carries information away from the
cell body to various muscle, glands, and neurons in the body. Hence
option (d) is the correct answer
20) Nerves are bundled axons that connect the central nervous
system with various glands and muscles in the body. Hence option
(c) is the correct answer.
21) The peripheral nervous system is broadly classified into 2
types such as somatic and autonomous nervous system. Hence option
(d) is the correct answer
22) REM Sleep otherwise known as Rapid Eye Movement sleep is
also known as paradoxical sleep. This is primarily because our
muscles are completely relaxed while our brain and nervous system
are fully active which gives us dreams. Hence option c which reads
our nervous system is highly active while our voluntary muscles
hardly move is the correct answer.