BIO FINAL CARDS

Sensory axons enter the spinal cord through

The resting potential of a neuron is due mostly to

At equilibrium, when the neuron is at rest,

At the peak of the action potential

The depolarization phase of an action potential is due to 

At the neuromuscular junction, which ion triggers the release of neurotransmitter by causing synaptic vesicles to fuse with the presynaptic membrane?

_____, is the enzyme responsible for breaking down acetylcholine into _____ and _____. 

Sickle-cell anemia first appeared in Asia, the Middle East, and Africa. The causative allele entered the U.S. population when people were forcibly brought over from Africa prior to the Civil War. In microevolutionary terms, this is a case of _____ . 

Directional selection occurs when

Stabilizing selection occurs when 

The introduction of a small population onto an island that results in a limited gene pool for a population best describes 

The sharp reduction of the gene pool and the numbers of a population through a severe epidemic is an example of 

Directional selection 

In the biological species concept of Ernst Mayer, what aspect of a population is critical to determining a species?

The primary reason for hybrid sterility is