<span>8. Chitinase is an enzyme that breaks down the chitin molecules in an insect's exoskeleton. The sequence of amino acids in the chitinase is an example of which level of protein structure?
==> primary
9. The amount of energy needed for a reaction to take place is the activation energy. Enzymes can lower the activation energy of a chemical reaction. Which of the following describes a way that this could happen?
==> Molecules can be brought together so they will bond more easily.
10. What is one way that RNA differs from DNA?
==> It is single-stranded.
11. Which molecule do mammals use to store extra glucose in their muscles?
==> glycogen
12. Which molecule do plants use to store extra glucose?
==> starch
13. Which element is present in all amino acids, but not necessarily in fats or carbohydrates?
==> nitrogen
14. Which statement best describes the role of DNA in the body?
==> It contains genetic information.
15. Which statement best explains how enzymes speed up chemical reactions?
==> Enzymes lower the activation energy of a reaction.</span><span>
</span>
Answer:
B
Explanation:
the nutrient that is required for repairing cells is protein
Human Immunodeficiency Virus -- this is HIV, the virus that causes AIDS.
Flu viruses. There are lots of different strains of flu virus, which is why new vaccines have to be made every year.
Cold virus. The common cold is caused by a virus.
Mutation is the primary cause of all genetic variation. Mutation is important as the first step in evolution, as it produces a new sequence of DNA for a particular gene, producing a new allele. Recombination, through intragenic recombination, may also generate a new DNA sequence (a new allele) for a particular gene.
