p53 is a famous tumor suppressor, which blocks cell cycle progression preventing damaged/mutated DNA from being duplicated. Proto oncogenes are normal genes that regulate cell growth and proliferation. Oncogenes are mutated proto oncogenes that lead to unregulated cell proliferation. The checkpoints are in the S, G1, G2/M phases.

In metaphase, spindle fibers align chromosomes along the middle of the cell nucleus. A good way to remember this is "M" in metaphase stands for middle. In this portion of mitosis, the cell ensures that each daughter cell will receive the appropriate genetic material. Metaphase occurs right before Anaphase.

Cytokinesis is the last processes of cell replication and division and consists of the cell membrane dividing into two.

Prophase and metaphase happen before anaphase, and the duplicated chromosomes (sister chromatids) condense and align. During anaphase they are pulled apart and start migrating to opposite cell poles. Telophase and cytokinesis follow anaphase to complete the division of the cell into two new cells.

Diploid means 2_n_, where n is the number of chromosomes in a particular species. If there are 10 chromosomes, there will be 20 chromatids. For each chromosome there are two chromatids. Since this is before the cells have fully divided, there will be 2 times the number of chromosomes during prophase. Therefore, the answer is 20.

The S phase is the "synthesis" phase, where DNA is duplicated. Cells that are not dividing are considered to be in the G0 phase, however, they can enter the cell cycle if they receive the proper signals. The S phase occurs before the M phase (mitosis) as the cell begins to prepare for division.

During Meiosis, the cell starts with 2n in interphase, then duplicates its DNA to have 4n throughout prophase I, metaphase I, and anaphase I. The cell then splits in two during telophase/cytokinesis, and there are 2n during prophase II, metaphase II, and anaphase II. The end product after telophase II is 1n.

The correct answer here is the fiber connecting the chromosomes in the initial stages of mitosis. Remember that during mitosis, 1 pair of chromosomes becomes 2 new pairs. This requires the pair to split initially, duplicate, then break off into the new cells. The last stage of cell division is called anaphase, not a centromere. A centromere is the middle of a pair of chromosomes, not the individual chromosome. If you chose the daughter cell, remember that centromeres are not describing the new cell itself, but the connection between chromosomes inside the cell.

The correct answer is that they are the fibers that help move the chromosomes towards a certain side of the cell during mitosis. If you chose the option about connecting a pair of chromosomes, remember that this is called a centromere and is also vital in mitosis. If you chose that the spindle fibers are only necessary in meiosis, remember that even in mitosis, fibers are needed to separate the individual chromosomes to form a new cell. Fibers do not act as the primer in RNA production

G2, or Gap 2 phase, is the third and last subphase of interphase, preceding mitosis. S phase is the phase in which DNA is duplicated and G1 has the first checkpoint. G0 is the phase where cells do not divide anymore, also known as the resting phase.