On her first birthday, Alena takes her first steps, which are clumsy and awkward. By her second birthday, her steps are
smooth and coordinated. This transition in Alena’s walking skills best illustrates the concept of:
a. imprinting.
b. hard-wiring.
c. reflex action.
d. synaptic plasticity.
e. voluntary acquisition.
d
You might also like to view...
What is one reason that RNA viruses and retroviruses have such a high rate of mutation?
A. because RNA replication is much more prone to mistakes B. because RNA viruses and retroviruses initially cause mutations during replication C. because RNA is more fragile than DNA and therefore more likely to be damaged D. because they lack a proofreading mechanism E. because RNA is more fragile than DNA and because viral polymerases lack a proofreading mechanism.
tRNA differs from other types of RNA because
it
a. acts as an enzyme. b. is only involved in transcription. c. carries amino acids. d. codes for multiple amino acids. e. is complexed with a protein
To create transgenic mice, DNA is injected into
A) a pronucleus of a zygote. B) the cytoplasm of a zygote. C) the nucleus after the pronuclei have fused. D) a pronucleus of one cell from an embryo.
In humans, what percent of the genome is devoted to the exons that encode proteins?
A. about 50% B. about 35% C. about 75% D. about 20% E. about 1.5%