Answer:
The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells. Rudolf Virchow later made important contributions to this theory.
Explanation:
The forelimbs of all mammals are homologous traits, meaning that they originate from a common ancestral trait.
The correct answer is therefore C. Homologies (homologous traits), from the same common ancestor.
(To clarify, we know it is from a common ancestor because both bats and humans are mammals)
Hello!! The answer would be A - The SA node. It is known as the "pacemaker" because it initiates the heart's rhythmic contractions. I hope I helped!! Have a great day. :)
Answer:
A nucleotide is made up of one sugar molecule, one phosphate molecule and one of the four bases. Here is the structural formula for the four nucleotides of DNA. Note that the purine bases (adenine and guanine) have a double ring structure while the pyrimidine bases (thymine and cytosine) have only a single ring.
Explanation:
A nucleotide is made up of one sugar molecule, one phosphate molecule and one of the four bases. Here is the structural formula for the four nucleotides of DNA. Note that the purine bases (adenine and guanine) have a double ring structure while the pyrimidine bases (thymine and cytosine) have only a single ring.