Which Best Describes Brain Development from Birth Through Adolescence

question 47

Multiple Choice

Which best describes brain development from birth through adolescence?

• A) Synapses are pruned in early childhood as a response to the environment but grow back in adolescence as the child matures.
• B) Synapses that are unused are pruned while myelination of the axon increases the efficiency of communication between childhood and adolescence.
• C) Dendrite and axon communication becomes less efficient as the child moves into adolescence.
• D) Axons and dendrites expand in the number of connections they make during the adolescent years.
• E) Axons and dendrites become thinner and more sparse throughout childhood and adolescence.

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Definitions:

Directional Selection

A type of natural selection where an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time.

White-Coated Hares

Refers to the snowshoe hare (Lepus americanus), which changes its coat color from brown to white in the winter to blend in with snow as a camouflage against predators.

Ice Age

A period of long-term reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.

Derived Trait

A trait that is present in an organism but was absent in the last common ancestor of the group, indicating an evolutionary change.