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Multiple choice-answer the one you know for sure please n thank you dont answer all if you dont know it at least one helps
1)Given a population that contains genetic variation, what is the correct sequence of the following events, under the influence of natural selection?
1. differential reproduction occurs.
2. a new selective pressure arises.
3. Allele frequencies within the population change.
4. poorly adapted individuals have decreased survivorship
2) To observe natural selection's effects on a population, what must be true?
a. one must observe more than one generation of the population
b. the population must contain genetic variation
c. members of the population must increase or decrease the use of some portion of their anatomy
d. A and C only
e. A and B ony
3) in hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish, i.e., they locate their prey by sight. If a population of algae eaters experiences predation pressure from pike-cichlids, which of the following would least likely be observed in the algae-eater population over the course of many generations?
a. coloration of the algae eaters may become drab
b. the algae eaters may become nocturnal ( active only at night).
c. female algae eaters may become larger, bearing broods composed of more, and larger, young.
d. the algae eaters may become sexually mature at smaller overall body sizes.
e. the algae eaters may become faster swimmers.
4) A biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of competition for food and predation. In a single generation, 90% of the squirrels that were born live to reproduce, and the population increased to 80. What interferences might you make about this population?
a. the amount of available food may have increased
b. the number of predators may have decreased.
c. the squirrels of subsequent generations should show greater levels of variation than previous generations because squirrels that would not have survived in the past will now survive.
d. a and b only
e. a, b, and c
5) which of the following is the best example of humans undergoing evolution, understood as "descent with modification"?
a. reduction in the amount and coarseness of body hair over millennia
b. reduction in numbers of hairs on the head of a balding person
c. increased pigment production by the skin of a person who is exposed to increased UV radiation lights
d. increase in weight over an individual's lifetime
e. widening of the pupils of the eyes when one encounters dimly lit conditions.
6) Which statement best describes how the evolution of pesticide resistance occurs in a population of insects?
a. individual members of the population slowly adapt to the presence of the chemical by striving to meet the new challenge.
b. all insects exposed to the insecticide begin to use a formerly silent gene to make a new enzyme that breaks down the insecticide molecules.
c. insects observe the behavior of other insects that survive pesticide application, and adjust their own behaviors to copy those of the survivors.
d. a number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals.
e. b and d only
1)Given a population that contains genetic variation, what is the correct sequence of the following events, under the influence of natural selection?
1. differential reproduction occurs.
2. a new selective pressure arises.
3. Allele frequencies within the population change.
4. poorly adapted individuals have decreased survivorship
2) To observe natural selection's effects on a population, what must be true?
a. one must observe more than one generation of the population
b. the population must contain genetic variation
c. members of the population must increase or decrease the use of some portion of their anatomy
d. A and C only
e. A and B ony
3) in hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish, i.e., they locate their prey by sight. If a population of algae eaters experiences predation pressure from pike-cichlids, which of the following would least likely be observed in the algae-eater population over the course of many generations?
a. coloration of the algae eaters may become drab
b. the algae eaters may become nocturnal ( active only at night).
c. female algae eaters may become larger, bearing broods composed of more, and larger, young.
d. the algae eaters may become sexually mature at smaller overall body sizes.
e. the algae eaters may become faster swimmers.
4) A biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of competition for food and predation. In a single generation, 90% of the squirrels that were born live to reproduce, and the population increased to 80. What interferences might you make about this population?
a. the amount of available food may have increased
b. the number of predators may have decreased.
c. the squirrels of subsequent generations should show greater levels of variation than previous generations because squirrels that would not have survived in the past will now survive.
d. a and b only
e. a, b, and c
5) which of the following is the best example of humans undergoing evolution, understood as "descent with modification"?
a. reduction in the amount and coarseness of body hair over millennia
b. reduction in numbers of hairs on the head of a balding person
c. increased pigment production by the skin of a person who is exposed to increased UV radiation lights
d. increase in weight over an individual's lifetime
e. widening of the pupils of the eyes when one encounters dimly lit conditions.
6) Which statement best describes how the evolution of pesticide resistance occurs in a population of insects?
a. individual members of the population slowly adapt to the presence of the chemical by striving to meet the new challenge.
b. all insects exposed to the insecticide begin to use a formerly silent gene to make a new enzyme that breaks down the insecticide molecules.
c. insects observe the behavior of other insects that survive pesticide application, and adjust their own behaviors to copy those of the survivors.
d. a number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals.
e. b and d only