Which developmental change in the brain occurs after birth?
a. The number of dendrites and synapses increases until adolescence, when they are reduced.
b. The number of axons increases and the number of dendrites decreases throughout adolescence and adulthood.
c. No developmental changes occur after birth because all the neurons the brain will ever have are present at birth.
d. New neurons grow until adolescence, when they begin to die.
Question 2
Marco works for a research company investigating stem cells. Their goal is to find ways of treating people with spinal cord injuries by replacing damaged neurons with new ones. According to the textbook, the challenge of generating new neurons is finding out how____.
a. to promote the receptors for Nogo proteins
b. the new cells can reestablish all of the connections that had been lost
c. to block neurotrophic factors which inhibit the growth of new neurons
d. undamaged neurons take over for damaged ones
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