Answer:
The correct answer is option c.
Explanation:
The G1 phase of the cell cycle refers to the initial phase of the cell cycle or the first phase of the cell division that needs some additional growth element called mitogen in order to carry on the process. However, these mitogens are needed until the cell attains a particular state in the G1 phase.
If the mitogens are withdrawn prior to that state, the cell cycle will get an arrest. Once the cell has reached and passed that state it becomes completely independent of mitogen and does not care for the presence of mitogen. This state is called restriction point, which usually takes place in late G1 phase.
After passing the restriction point, the cell is destined to go through the process of mitosis regardless of the absence of existence of mitogen. Thus, the correct answer is option c.
The separation of the sister chromatids during the cell division occurs in the anaphase in mitosis and anaphase II in meiosis.
During the anaphase in mitosis, and the anaphase II of the meiosis, the chromosomes aligned at the center of the nucleus separates and the sister chromatids of the chromosomes starts moving towards the opposite poles as the spindle fibers starts contracting.
I believe when DNA is denatured by heat, hydrogen bonds are separated to create single stranded DNA. When the DNA solution is heated enough, The double stranded DNA unwinds, and the Hydrogen bonds that hold the two strands together weaken and finally break. The process of breaking a double-stranded DNA into single strands is known as DNA denaturation, or DNA melting.
