I took the test and the answer is not shear, so don't put that one. My next choice would have been strain.
Answer:
A. single-gene
Explanation:
It is controlled by a single gene that has two alleles. The allele for a widow's peak is dominant over the allele for a hairline with no peak.
Answer:
B
Explanation:
Neurotransmitters such as acetylcholine, epinephrine are important at a neuron-neuron junction called synapses. When an impulse reaches the end of one neuron, at the synapse, it causes the release of neurotransmitters from synaptic vesicle that diffuse across the synapse and when they bind to their reports on the other end. An impulse is then generated on the subsequent neuron that travels down the axon to the next synapse.
The best estimate for Earth's age is based on radiometric dating of fragments from the Canyon Diablo iron meteorite. From the fragments, scientist calculated the relative abundances of elements that formed as radioactive uranium decayed over billions of years.