p53 is sometimes referred to as "the guardian of the genome" due to its huge role in suppressing the propagation of cells containing permanent DNA damage. If DNA damage is detected, p53 becomes activated and acts to promote cell cycle arrest. This gives the cell a chance to repair its genome by activating the appropriate DNA repair pathways (for which p53 is also responsible).

p53 also plays a role in promoting apoptosis. If the DNA damage is irreparable, the cell will go through apoptosis to prevent propagation of this damage.

Damage to the p53 gene can lead to unmitigated cell division and tumor formation, marking p53 as a proto-oncogene.

All of the choices are potential reasons for cell cycle arrest.

DNA damage activates pathways (commonly through the protein p53) in an attempt to repair the damage or activate apoptotic pathways if the DNA damage cannot be fixed. This causes arrest of the cell cycle at the G2 checkpoint.

Lack of appropriate growth factors will keep the cell from progressing through the cell cycle. Prolonged lack of growth is sometimes referred to as G0 of the cell cycle, and occurs when the cell cannot pass the G1 checkpoint.

Failure to properly align the chromosomes along the equatorial plate during mitosis will prevent the cell from activating pathways to degrade the cohesin that holds the sister chromatids together. This is a method to ensure proper segregation of chromosomes, and is known as the metaphase checkpoint.

During the pachytene stage of prophase I in meiosis, chromosomes have become condensed and form synapses. This is also when crossover, which is important to genetic diversity, takes place.

Tetrads do not move toward the midline until later in the meiotic processes.

There are four main phases in the cell cycle: G1 phase, S phase, G2 phase, and mitosis (M phase). G1 involves cell growth and preparation for DNA replication, S phase involves replication of the genetic material (DNA), G2 phase involves more cell growth and preparation for mitosis, and mitosis involves the division of the cell into two identical daughter cells. G0 phase is another phase that cells can undergo where they remain quiescent. This phase usually occurs after mitosis, when the cell is preparing to enter the G1 phase. Genetic material is increased in S phase only and cell growth occurs in G1 and G2 phases only, thus two of the answer choices are correct.

Progression through the cell cycle involves several molecules. There are several checkpoints along the cell cycle to ensure that the cell is ready for the next phase. One of the most important molecules involved in this process are the cyclin-dependent kinases (CDKs). These molecules phosphorylate and activate molecules that are important for the cell cycle. Inhibiting CDKs by an inhibitor will halt the activity of these molecules and, subsequently, the progression of the cell cycle.

DNA polymerase is an enzyme involved in DNA replication. It promotes DNA replication and helps the cell progress through the cell cycle. p53 is a tumor suppressor gene that is important for halting uncontrolled growth of cells. This is one of the most common mutated genes found in tumors. Lack of p53 activity leads to decreased regulation of cell growth. This means that cells can proliferate uncontrollably and can eventually become tumors.

There are three main checkpoints in the cell cycle. The first checkpoint occurs between G1 and S phase. During this checkpoint, the cell checks the stability of DNA molecules and the machinery required for DNA replication. If everything is fine, then the cell progresses into the S phase for DNA replication. The second checkpoint occurs between G2 phase and mitosis. During this checkpoint, the cell checks whether DNA replication occurred properly and whether the cell is ready for cell division. The third and final checkpoint occurs between the metaphase and anaphase of the cell. During this checkpoint, the cell checks whether the spindle apparatus is properly formed for anaphase and subsequent steps in mitosis.

DNA replication occurs during the S phase. Upon completion of DNA replication, a cell has a duplicate copy of every chromosome it possesses. Recall that humans have 2 sets of 23 chromosomes (total of 46 chromosomes). For example, there are two different copies of chromosome 1, two different copies of chromosome 2, etc. The two different copies of chromosomes are termed homologous chromosomes. Upon completion of DNA replication, each of these 46 chromosomes will have an identical duplicate copy, called the sister chromatid. The sister chromatid is attached to the original chromosome at the centromere. This entire entity, however, is still considered a single chromosome; therefore, upon completion of S phase humans will have 46 chromosomes.

The organism in the question has 50 chromosomes to begin S phase (2n = 50); therefore, it will have 50 chromosomes at the end of S phase.

Neural Cells are arrested in the  phase to prevent growth. This arresting phase prevents abnormal growth and cancer cells development.  and  involve cell growth and duplication of organelles.  phase is the time in which DNA is duplicated, and  phase stands for mitosis, or meiosis, in which the nucleus divides.

This is a tricky question because all of the choices are correct, except for one minor part. Meiosis sees cells undergo a reduction division in the first division. That means that after the first meiotic division, the diploid germ cell has become a haploid.

Meiosis is the process by which haploid gametes are produced. The attachment of a haploid sperm to a haploid egg begins the process of development and fertilization. In humans a sperm containing 23 chromosomes joins with an egg containing 23 chromosomes to create an organism with 46 chromosomes.

If meiosis were to produce diploid gametes, then the diploid gametes would combine to form an organism that contains twice as many chromosomes as the parent. For example, a diploid sperm and egg (containing 46 chromosomes each) would create an organism with 92 chromosomes. This new organism would produce another organism with 184 chromosomes (double 92). The subsequent generations would have twice as many chromosomes as the previous generation, and the amount of chromosomes would increase exponentially.

Offspring 1: 92 chromosomes

Offspring 2: 184 chromosomes

Offspring 3: 368 chromosomes

The best answer is that the number of chromosomes in subsequent generations would increase exponentially.