G1 phase is the first phase of the interphase of the cell cycle in which cell shows a growth by synthesizing proteins and other molecules. G2 phase is the third phase of interphase of the cell cycle in which cell prepares for nuclear division by making necessary proteins and other components.

During G1 phase, the cell grows in size and synthesizes mRNA and protein that are required for DNA synthesis. Once the required proteins and growth are complete, the cell enters the next phase of the cell cycle, S phase.

Initially in G1 phase, the cell grows physically and increases the volume of both protein and organelles. In S phase, the cell copies its DNA to produce two sister chromatids and replicates its nucleosomes. Finally, G2 phase involves further cell growth and organisation of cellular contents.

What happens during the G1 phase? The cell prepares for division and copies organelles. This phase includes both mitosis and cytokinesis, during which the chromosomes are sorted and separated to ensure that each daughter cell receives a complete set. After this, cytokinesis divides the cell in two.

Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.

Explanation: There are two stages in the cell cycle marked by the replication of organelles and protein synthesis: G1 and G2. G1 follows mitosis and allows the cell to grow. G2 occurs just before mitosis, and ensures that both daughter cells will have adequate organelles.

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interphase

The G2 phase is the time during which a cell replicates its organelles in preparation for mitosis. Not only does the DNA need to be divided, but so do the organelles. G2 is the last chance for the cell to make more protein in preparation for division.

Cdk (cyclin dependent kinase, adds phosphate to a protein), along with cyclins, are major control switches for the cell cycle, causing the cell to move from G1 to S or G2 to M. MPF (Maturation Promoting Factor) includes the CdK and cyclins that triggers progression through the cell cycle.

Before the G2 phase can start, each chromosome of the cell must have been duplicated, and the proteins required for the extra cell membranes and cell structures must be present. At the beginning of G2, the organelles such as the mitochondria and the lysosomes start multiplying.

DNA replication occurs during this S (synthesis) phase. Gap 2 (G2): During the gap between DNA synthesis and mitosis, the cell will continue to grow and produce new proteins. At the end of this gap is another control checkpoint (G2 Checkpoint) to determine if the cell can now proceed to enter M (mitosis) and divide.

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If errors or damage are detected, the cell will pause at the G 2​start subscript, 2, end subscript checkpoint to allow for repairs. If the checkpoint mechanisms detect problems with the DNA, the cell cycle is halted, and the cell attempts to either complete DNA replication or repair the damaged DNA.

S phase or synthesis phase is the second sub-phase of interphase. G2 or Gap2 phase is the third and last sub-phase of interphase that directly leads to divisional phase. It occurs in between the G1 (Gap 1) phase and G2 (Gap 2) phase. It occurs in between the S phase and divisional phase or mitosis.

What would happen if the G2 phase didn’t function properly? No cellular proteins could be made. The DNA would not be replicated. The spindle apparatus would not form.

Answer: During the G1 phase, the cell shows first growth by copying organelles and making the molecular building blocks which are necessary for later steps. During the G2 phase, the cell shows the second growth by making proteins and organelles and beginning to reorganize its contents in preparation for mitosis.

The G2 checkpoint prevents cells from entering mitosis when DNA is damaged, providing an opportunity for repair and stopping the proliferation of damaged cells. Because the G2 checkpoint helps to maintain genomic stability, it is an important focus in understanding the molecular causes of cancer.

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Big Major Test

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The S phase of a cell cycle occurs during interphase, before mitosis or meiosis, and is responsible for the synthesis or replication of DNA. In this way, the genetic material of a cell is doubled before it enters mitosis or meiosis, allowing there to be enough DNA to be split into daughter cells.

Synthesis Phase

G1 is typically the longest phase of the cell cycle. The length of S phase varies according to the total DNA that the particular cell contains; the rate of synthesis of DNA is fairly constant between cells and species. Usually, cells will take between 5 and 6 hours to complete S phase.

During S phase, which follows G1 phase, all of the chromosomes are replicated. Following replication, each chromosome now consists of two sister chromatids (see figure below). Thus, the amount of DNA in the cell has effectively doubled, even though the ploidy, or chromosome count, of the cell remains at 2n.

2 Answers. During S phase (synthesis), DNA replication takes place. Completion of DNA synthesis is followed by G2 phase during which cell growth continues and proteins are synthesized in preparation for mitosis. S page lasts for 8 hours approximately.

Gene mutation has to do with the duplication of the DNA, and if something wrong goes with this duplication, then the new DNA will not be exactly like the original one. This duplication happens in the S phase. Chromosomal mutation are either having an extra or missing piece, or having an extra or missing chromosome.