In a molecule of DNA, Adenine (A) always pairs with

The Punnett Square below shows a cross between an Ss parent and an ss parent.  What is the probability that their child will have short big toes? 

Which of the following shows a homozygous genotype?  Choose all that apply. 

Which of the following shows a heterozygous genotype? 

Glacier bears are an Alaskan subspecies of the American black bear. Glacier bears have a rare dark grayish-blue fur.  Some glacier bears live in the same areas as black bears. A glacier bear and a black bear can mate and produce cubs. Studies show that the allele for black fur is dominant and the allele for gray-blue fur is recessive. The gene for fur color can be represented by the letter G or g. 

What is the genotype for a gray-blue glacier bear?

Albinism is a genetic trait in which a person produces little to no melanin, or pigment.  An albino person's skin and hair are much lighter than normal.  Albinism is a recessive trait.  

The pedigree in the attached image shows a family with a few albino members.  Shapes representing family members with albinism are shaded.  Based on the pedigree, which of the following statements is correct? 

Which is the first step in protein synthesis?

After DNA is unzipped in the nucleus, what is the next step in protein synthesis?

After mRNA is transcribed from DNA, what is the next step in protein synthesis?

After mRNA moves to the ribosome, what is the next step in protein synthesis?

What is the final step of protein synthesis?

The sequence of ________________ in a DNA molecule determines the protein that will be produced.

Humans have 23 pairs of chromosome in every body cell. Even one extra chromosome causes death or serious disorders. For example, an extra copy of chromosome 21 causes Down syndrome. How many chromosomes does every body cell have in a human with Down syndrome?

Darren is a world-class runner, and he recently learned that he has a mutation in the gene controlling his fast-twitch muscles. This helps explain his high level of ability. 

This is an example of what kind of mutation?