Why was the reduction of the bison population to under 1,000 individuals a bottleneck event for the species? a. It drastically reduced the gene pool of the species. b. It reduced the territorial range available to the species. c. Foreign genes were introduced by crossbreeding with cattle. d. It reduced the prevalence of recessive traits.

The correct answer is - option A.  It drastically reduced the gene pool of the species.

Explanation:

A population bottleneck is a process that definitely decreases the size of a population. The bottleneck might be brought about by different occasions, for example, an ecological disaster, the hunting of animal groups to the point of elimination or extinction, or territory obliteration that outcomes in the deaths of creatures.  

Bottleneck occasions are named because of the extraordinary loss of genetic diversity. In spite of the fact that this can now and then bamboozle because of certain species colossal contrasts between the genuine populace and compelling populace.

the answer is "a.) well–developed vascular system."

explanation:

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.