67 points plus brainlest if done correctly.I will report you if you answer 3 or less of the questions, also must post all the answers at the same time.


21.
What explains why human eyes come in a variety of colors?

Many phenotypes have pairs of alleles.

Multiple genes each have only one allele.

Multiple alleles result in many phenotypes.

Different phenotypes result in different genes.


22.
Adults with Down syndrome can often find work because they have received _____.

folic acid

physical therapy

genetic counseling

education and job training


23.
Which describes a karyotype?

a picture of the chromosomes in a cell

fluid that surrounds a baby before it is born

a picture of a baby before it is born

a sex-linked genetic disorder


24.
Traits that are controlled by many different genes have _____.

two distinct phenotypes

only one phenotype

many different phenotypes

a couple of phenotypes


25.
What controls variations in skin color among humans?

a person’s diet

multiple alleles of a single gene

two alleles of a single gene

many genes