<h3><u>Answer and Explanation</u>;</h3>
- Purines: Heterocyclic rings are synthesized one atom at a time, first atom attached to ribose phosphate (source is PRPP) and then all the other atoms are added .
- Pyrimidines: Common intermediate, orotate, synthesized first, then orotate is attached to ribose phosphate (source is PRPP or 5-Phosphoribosyl-1-pyrophosphate).
Answer:
The xylem consists of tracheary elements, xylem parenchyma cells, and xylem fiber cells.
Answer:
No, mutations do not all result in negative effects. Sometimes they can be beneficial, as they are completely random. It is our general tendency to think of the word "mutation" in negative terms; however, do not get confused. Mutations are the root/ultimate source of genetic variation; they are one of the main factors that allow populations to evolve.
