Annual rings in woody stems are caused by an increase in rings of the
a. primary xylem.
b. primary phloem.
c. secondary phloem.
d. secondary xylem

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.

Which process the first step in making a protein from dna intrsuction