Explain how dna is involved in creating genetic variation within a species. is this considered a mutation, if so why?

Which sentence best expresses the differing opinions of these two book reviews?

What organ is the first to receive nutrients that have been absorbed from the digestive tract?

Cancer cells spread to other parts of the body by entering the bloodstream. which of the following organs could prevent a cancer cell in the bloodstream from spreading, and why? a. the spleen, because it releases lymphocytes into the blood b. the peyer's patches, because they release lymphocytes into the blood c. the lymph nodes, because they release lymph into the blood d. the thymus, because it releases lymph into the blood