Which of the following genotypes is homozygous dominant?

a.) tt
b.) ff
c.) xy
d.) ss

Proteins are made from amino acids. an amino acid has three parts that are joined to a central carbon atom. identify the three parts that create an amino acid.

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above

Which star has the highest apparent magnitude?