Chapter 4

Suppose you have high sensitivity to tasting PTC. If your mother can also taste it easily, what (if anything) can you predict about your father's ability to taste it?

Suppose someone identifies a "gene for" certain aspects of development. How might that statement be misleading?

How does an epigenetic change differ from a mutation?

Suppose someone determines the heritability of \(1 Q\) scores for a given population. Then society changes in a way that provides the best possible opportunity for everyone within that population. Will heritability of IQ increase, decrease, or stay the same?

What are plausible ways for possible altruistic genes to spread in a population?

Which comes first: migration, synaptogenesis, or myelination?

If axons from the retina were prevented from showing spontaneous activity during early development, what would be the probable effect on development of the thalamus?

What process assures that the spinal cord has the right number of axons to innervate all the muscle cells?

At what age does a person have the greatest number of neuronsearly in life, during adolescence, or during adulthood?

Anesthetic drugs and anxiety-reducing drugs increase activity of GABA, decreasing brain excitation. Why would we predict that exposure to these drugs might be dangerous to the brain of a fetus?

Which brain area shows expanded representation of the left hand in people who began practicing stringed instruments in childhood and continued for many years?

Why is immaturity of the prefrontal cortex not a satisfactory explanation for risley behaviors in adolescents?

What is one way in which older adults compensate for less efficient brain functioning?

What are the two kinds of stroke, and what causes each kind?

Why is tPA not helpful in cases of hemorrhage?

Is collateral sprouting a change in axons or dendritic receptors?

Is denervation supersensitivity a change in axons or dendritic receptors?