这关键区别between G1 G2 and S phase is the growth that occurs.在G1阶段，该单元通过复制细胞器和制造分子构建块显示出首先生长，这是以后步骤所必需的；在G2阶段，该细胞通过制造蛋白质和细胞器来显示第二个生长，并开始重新组织其含量以准备有丝分裂。在S相中，细胞复制或复制细胞中的所有DNA，形成了额外的染色体。
真核细胞随着细胞的生长和发展而经历细胞分裂。细胞周期中有两个主要阶段。他们是interphase and mitosis。一个分裂的单元将大部分时间都花在相间。换句话说，相间是细胞周期中最长的相位，其中细胞为核分裂准备并产生新的子细胞。相间的相间进一步细分为三个阶段，作为差距1（G1）相，差距2（G2）相和合成相。G1相是相互阶段的第一阶段，它是一个更长的过程。S相是细胞对其染色体集的额外副本的中间阶段。G2相是相对的最后阶段，是相对较短的相。
CONTENTS
1。概述和关键差异
2。什么是G1阶段
3。什么是G2阶段
4。什么是s阶段
5。G1 G2和S相之间的相似性
6.并排比较 - G1 vs G2 vs S相在表格中
7.Summary
什么是G1阶段？
差距1或G1期是冷杉st cell growth phase of the interphase of the cell cycle. Significant development processes take place within the cell during the G1 phase. The cell size will increase due to the extensive synthesis of proteins and RNA.蛋白质的合成在发生DNA复制的S相之前，需要RNA。在G1期合成的蛋白质主要包括组蛋白蛋白，而大多数RNA synthesizedis mRNA. Histone proteins and mRNA participate in the S phase for DNA replication.
细胞周期的持续时间根据生物的类型而变化。一些生物在进入S阶段之前具有更长的G1相，而其他生物可能具有较短的G1相。在人类中，典型的细胞周期运行18小时。在细胞周期的总时间中，G1相通常需要1/3的时间。但是，由于某些因素，这次可能会改变。这些因素称为生长因子，其中一些因素是细胞环境，蛋白质和特定氨基酸等营养素的可用性以及细胞温度。温度主要影响生物体的正常生长，并且该值因生物体而异。在人类中，细胞生长的最佳温度约为370C。
图01：细胞周期
这cell cycle regulatory mechanism controls the G1 phase. During the regulation, the control of duration and coordination between other phases take place. G1 phase is considered to be an important phase because it is the point which determines the fate of the cell. In this phase, the cell decides whether it proceeds with the rest of the phases of the cell cycle or leave the cell cycle. If the cell receives a signal to keep it at an un-dividing stage, the cell will not enter into the S phase. It will move into the dormant phase called G0 phase. G0 phase is a state of cell cycle arrest.
什么是G2期(又名差距2期）？
G2阶段，也称为Gap 2 phase, is the final phase of interphase. G2 phase is a shorter phase, but it is an important phase of the cell cycle. During the G2 phase, extensive cellular growth takes place under high synthesis rate of proteins. With the synthesis of necessary RNA and proteins, it also helps the formation of the spindle apparatus during mitosis. Even though this phase is important, a cell can bypass this stage and directly enter mitosis once the cell completes its S phase. But by completing the G2 phase, the cell can become fully prepared for mitosis or nuclear division.
如果细胞进入G2相，它证实了一个事实，即该单元已成功完成了发生DNA复制的S相。因此，G2相中的所有细胞都将发展为有丝分裂，其中细胞将分为两个相同的子细胞。在G2相中，细胞大小随不同成分（包括细胞核和几乎所有其他细胞细胞器）而增加。与G1相类似，G2相也受细胞周期调节机制的调节。
什么是S阶段？
S相或合成相是相间的中间阶段。在S阶段，该单元将其所有DNA复制并进行额外的副本。因此，染色体集的完整副本是在S相中合成的。此外，在S期间还合成了中心体。这些中心体用于有丝分裂期间的未来使用。中心体有助于DNA的分离。
图02：s阶段
A successful cell division depends on the duplication of its genome. It takes place during the S phase. S phase is the most critical phase of the cell cycle. Therefore, this phase is tightly regulated and widely conserved.
G1 G2和S阶段之间有什么相似之处？
- G1，G2和S相是细胞周期相间的三个阶段。
- 这三个阶段几乎都出现在所有细胞周期中。
- 在这些阶段，细胞生长，复制其染色体并准备细胞分裂。
- 这三个阶段的持续时间大于M相。
- 这三个阶段对于成功的细胞分裂都是至关重要的，非常重要。
G1 G2和S阶段有什么区别？
G1 phase is the first phase of the interphase in which the cell grows by copying organelles and synthesizing proteins and RNA. G2 phase is the third phase of the interphase in which cell makes proteins and organelles and RNA and reorganizes cell content. S phase is the middle phase of the interphase in which cell duplicates its DNA and centrosomes. So, this is the key difference between G1 G2 and S phase. G1 phase is the longest phase of interphase while G2 phase is the shortest phase of interphase and S phase is the second-longest phase of the interphase.
以下是所有3个阶段的详细并排比较，以辨别G1 G2和S相之间的差异。
摘要 - G1 G2与S阶段
Interphase is the longest phase in the cell cycle. During the interphase, the cell grows, replicates its DNA, accumulates nutrients and duplicates its organelles. By doing all these, the cell prepares for cell division and the making of new cells. There are three major stages in interphase as G1, S and G2 phases. G1 is the first phase, and during this phase, the cell grows larger, copies its organelles and makes the molecular building blocks. During the S phase, cell synthesizes a complete extra copy of its DNA. The cell also duplicates centrosomes that are required for DNA separation in mitosis. G2 is the last phase of the interphase, and during it, the cell grows more, synthesizes proteins and organelles and reorganizes cell contents. Thus, this is the summary of the difference between G1 G2 and S phase.
参考：
1。“Phases of the Cell Cycle (Article).” Khan Academy, Khan Academy,在这里可用。
2.“细胞周期”。Lumen，Redwoods＆Northern Virginia社区学院，在这里可用。
图片提供：
1. Boumphreyfr的“真核复制周期” - 自己的工作（CC BY-SA 3.0）通过下议院维基梅迪亚
2。“Asymmetry in the synthesis of leading and lagging strands”By David O Morgan – The Cell Cycle. Principles of Control. (Attribution) via下议院维基梅迪亚
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