3-6 The appropriate decisions to enter the s phase and the M phase of the cell c

Question

3-6

The appropriate decisions to enter the s phase and the M phase of the cell cycle depend on a pair of biochemicals called A) actin and myosin. B) CDKs and cyclin. C) ligand and receptor. D) MSH and MSH-receptor. E) ATP and ATPase. DNA replication occurs during A) anaphase. B) prophase. C) G1. D) S. E) G2. The products of mitosis are A) one nucleus containing twice as much DNA as the parent nucleus. B) two genetically different nuclei C) four nuclei containing half as much DNA as the parent nucleus. D) four genetically identical nuclei. E) two genetically identical nuclei. The mitotic spindle is composed of A) chromosomes. B) chromatids. C) microtubules. D) chromatin. E) centrosomes.

Explanation / Answer

Answer:

3). B. CDKs and cyclins

In order to drive the cell cycle forward, a cyclin must activate or inactivate many target proteins inside of the cell. Cyclins drive the events of the cell cycle by partnering with a family of enzymes called the cyclin-dependent kinases (Cdks).

4). D. S phase

S= Synthetic phase, in which DNA replication (doubling) takes place.

5). E). Two genetically identical nuclei

Mitosis is an equal division in which recombination of chromosomes doesn't occurs. So it produces two genetically identical nuclei.

6). C). Microtubules

Spindle fibers are made up of microtubules. These clusters of microtubules are responsible for moving chromosomes during cell division. Spindle fibers are created at the opposite poles of the cells during the prophase stage of mitosis.

Related Questions

Navigate

• Browse (All)
• Browse 3
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.