The correct answer is that dendrites are the sole receiver of stimulation because the soma of the neuron can also receive input from other cells. The other answers were wrong because they are true characteristic of the nervous system. Summation can be temporal or spatial depending on the amount of cells communicating with the neuron. One pre-synaptic cell can send input to the neuron multiple times to result in temporal summation, and multiple cells can send input to the same cell resulting in spatial summation. The total amount of input received by the dendrites and soma will sum in the initial segment of the axon, if the axon reaches the depolarization threshold, voltage gated sodium channels will open and set off a chain reaction that propagates the action potential to the axon terminal. This process is faster in cells with myelin because less of the axon needs to be stimulated to send the action potential to the terminal due to the insulation of segments by the myelin.

Nociceptors are sensory neurons that are activated by agitating or painful stimuli. Nociceptors respond to mechanical, thermal, and chemical stimuli to help protect the body from harmful interception.

All of the responses are true of PKU except that it is caused by a third 21st chromosome. Down Syndrome is caused by an extra copy of the 21st chromosome. Symptoms typically include delayed development, intellectual disability, and specific facial features. Unfortunately Down Syndrome cannot be managed by a change in diet. The most helpful interventions for Down Syndrome include parents, therapists, and teachers working together to support the child early on.

The cocktail party effect, demonstrated and named by Colin Cherry, illustrates people's ability to selectively attend to common stimuli--even in the presence of several conflicting conversations or auditory stimuli--which the brain identifies as more important. This is demonstrated by people's ability to hear their name, or the voice of a partner or friend, more clearly than other stimuli in a crowded environment.

The recency effect refers to a tendency to better recall the last items of a list, possibly because they are stored in a person's short-term memory; the primacy effect refers to a tendency to better recall the earliest items of a list, possibly because the person has had additional time to rehearse each one as it enters his/her long-term memory.

Telegraphic speech is speech during the two-word stage of language acquisition, consisting of commands or imperatives given in three-or-more word sentences consisting of functional words only. A sentence like "treat, bring now" contains enough to make the message effective, if not particularly precise.

Declarative and non-declarative, or implicit and explicit memory, are the two different categories of long term memory; they both are responsible for different types of memory encoding/retrieval, and their neural actions and reactions take place in different parts of the brain.

All of the responses are true of PKU except that it is caused by a third 21st chromosome. Down Syndrome is caused by an extra copy of the 21st chromosome. Symptoms typically include delayed development, intellectual disability, and specific facial features. Unfortunately Down Syndrome cannot be managed by a change in diet. The most helpful interventions for Down Syndrome include parents, therapists, and teachers working together to support the child early on.

Assuming that a food critic or wine taster most values their ability to perceive the flavors and aromas of these consumable items, then a loss of their sense of smell—olfactory loss—would be the greatest of these misfortunes they could suffer. The vestibular sense is that which informs us as to the orientation of our bodies in space. The semicircular canals contribute to this sense, and are housed within the inner ears. The loss of this sense might not compromise a food critic or wine taster as severely in their professional life. The striate cortex is a key component of the visual cortex, and damage therein would likely result in partial or total blindness. This would not hinder the food critic or wine taster's abilities to perceive their foods or wines however.

The frequency of a vibration corresponds to the pitch of the perceived sound produced from it. Higher frequencies will produce higher pitched notes, while lower frequencies will produce lower pitched notes. On the other hand, the amplitude of a sound wave will determine the volume of a perceived sound. Timbre is a complex component of a sound, and is the result of a variety of other elements. To provide a brief illustration however, timbre explains why a G# note on a trumpet sounds distinct from a G# note played on a piano. The longevity of a note is not the result of either the frequency or the amplitude of a sound. This is simply determined by how long the vibration continues.