Answer:
While it is difficult to determine exactly how many Natives lived in North America before Columbus, estimates range from a low of 2.1 million to 7 million people to a high of 18 million.
Explanation:
Answer:
d. They are often keystone species
Explanation:
Top predators in an environment are the largest predators and sits on the top (apex) of the food chain in an ecosystem which do not have any natural predators.
As the top predators relative to its abundance has disproportionately large effect on its natural environment, they are the keystone species most of the time.
Hence option d. They are often keystone species is the right option.
Answer: option B) A gene can take different forms called alleles.
Explanation:
An allele is one of the two or more different forms of the same gene.
For example, a trait such as seed shape is represented expressed a gene, but with allele of "RR" (round seeds) and "rr"(wrinkled seeds) observed physically by the farmers.
Thus, the correct answer is that a gene can take different forms called alleles.
By taking a glance at the pedigree we can see that rickets transmission is not autosomal but instead it is x linked recessive.
Without wasting time look at the no of offspring of 1 that is 4 since two out of four have rickets then the chances of having rickets by method of probability is 1/2
Please mark me as brainliest.
