1. Male dogs try to mate when they smell a female that is "in heat" What kind of stimulus are they responding to?
a) light
b) magnetic
c) chemical
d) mechanical

2. Many animals far from the equator enter a mating season as the days begin to lengthen, but this is not the case for animals near the equator. Why might these animals rely on different stimuli to begin mating?
a) there is always plenty of food near the equator
b)animals near the equator do not nurse their young
c)the length of the day at the equator does not vary much
d)There is too much light at the equator for animals to perceive

3. The following list of steps is out of order. What is the correct order in which these steps occur? 1. you flinch , 2. your ears send a signal along nerves to your brain, 3. a loud noise moves the bones inside your ears, 4. the brain sends a signal along your nerves to your muscles. In what order does it go?
a) 4,3,2,1
b) 3,2,4,1
c) 1,4,2,3
b) 4,3,1,2

4. A visual stimulus that leads to mating for peahens is the sight of a peacocks large, bright colored tail. Why might natural selection have given rise to this stimulus that signals a good mate?
a) Males with bright tails will draw predators away from the chicks
b) Males with larger tails can keep hens and chicks dry when it rains
c) Males with larger tails can provide more warmth when incubating eggs
d) Males with larger tails must have plenty of access to food because of the nutritional demands it takes to grow such plumage

5. Blue whales migrate to warm, tropical waters in the winter. They return to cold, polar waters in the summer, Calves are only born in winter. which of the following explains why?
a) there is more food for them to eat in the warm water
b) calves need to be born closer to the sun to learn how to migrate
c) calves would die of cold in the polar waters where the whales spend the summer
d) tropical oceans are more shallow, and the calves cannot swim well when they are born

6. You taste a new flavor ice cream. It is delicious! IT becomes your new favorite flavor. You remember how good it tasted, and you eat is as often as you can. At your next birthday, you ask if you can have some of that ice cream. In this scenario, what has your brain done with the information?
a) your brain processed that you liked the ice cream and then forgot the information each time
b) your brain stored a negative reaction to the ice cream
c) your brain stored the information that you liked the ice cream as a memory
d) your brain received information from your eyes that you liked the ice cream the first time

Answer and explanation:

1. The stimulus that males respond to when the female is "in heat" is a chemical stimulus (option c).

In the case of mating, many animals receive a chemical signal - called a pheromone - which indicates the optimal time for reproduction.

Pheromones are chemical substances produced by living beings that induce specific behavior in individuals of their same species, as happens with ants that produce the chemical signal that warns other hormihgas of the presence of food.

Females "in heat" are capable of producing and releasing this hormone, which the male picks up by his smell and is attracted to mate.

2. The reason why animals depend on different stimuli to mate when they are far and near the equator is that the the length of the day at the equator does not vary much (option c).

In countries far from the equator, with a temperate climate, there are seasons, in which variations in lighting or day and night vary, which is not the case near the equator.

When mating cycles depend on the presence or absence of daylight, it is logical to think that the mating of animals far from the equator will be different from those in a tropical climate, which represents a difference in the stimulus that determines mating.

3. The correct order in which these steps occur is 3,2,4,1 (option b). The correct sequence, then, is:

An intense sound stimulus, when produced, is captured by the hearing system, which makes the little bones of the middle ear vibrate, converting them into sound vibrations that the auditory nerve converts into nerve signals.

The nerve impulse travels by afferent route to the central nervous system, where the brain receives and relates it, and sends an efferent response that reaches the muscles and makes the individual flinch.

4. In the case of the peacock, and according to natural selection, the visual stimulus that leads to the mating of the peahen is a sign of good mating due to males with bright tails will draw predators away from the chicks (option a).

The real reason why Peahens choose male peacocks with a more colorful tail to mate is still controversial. However, it is a fact that the ocelli present in the peacock's tail help to keep predators away, which is a valid reason to justify sexual selection in this case.

The showiness of the tail in males of this species is also a sign of good genes and reproductive success.

5. With respect to blue whales, the reason that best explains why the calves are born in winter is that calves would die of cold in the polar waters where the whales spend the summer (option c).

Normally, blue whales tend to migrate during the winter to warmer waters with the intention of mating and having their calves.

The reason why birth occurs in winter is that the calves -despite their large size- have very little fat to protect them from the cold, so they are very sensitive to low temperatures.

The calves must remain around 6 to 7 months in a warm climate before migrating, time that they take advantage in being suckled, they reach their maturity and acquire a thicker layer of fat.

6. By relating the taste of ice cream to how nice it is to eat it, your brain stored the information that you liked the ice cream as a memory.

The human brain has the ability to store pleasant experiences, such as the taste of certain foods, because of the emotion they produce.

One of the functions of the brain is memory, a superior neurological function that allows it to relate different stimuli to the reactions they produce and to store them as a reminder, just as with the pleasant memory of the taste of ice cream.