The document explains the concept of the cell cycle, describing its phases, which include interphase (G1, S, G2) and the mitotic phase (M). It highlights the function of each phase in cell growth, DNA replication, and division, emphasizing that the interphase constitutes 95% of the cell cycle duration. The importance of cell division is also underscored, stating it supports survival, promotes growth, and replaces damaged or dead cells.

1. Concept Of Cell cycle phases
Before dealing with the concept of cell cycle phases it is crucial to know what cell
and cell cycle is in the first place. A cell can be defined as the basic and functional
unit of a living organism it can live on its and when similar cells are arranged
together they form tissue and organs. The structure of the cell encompasses several
organelles that have been listed below:
● Cytoplasm
● Cytoskeleton
● Endoplasmic reticulum (ER)
● Golgi apparatus
● Lysosomes and peroxisomes
● Mitochondria
● Nucleus
● Plasma membrane
● Ribosomes

2. What is a cell cycle?
The life cycle of a cell and the stages that it undergoes for the duplication of the cells
along with the DNA is referred to as the cell cycle. This concept was discovered by
Prevost and Dumas (1824) while researching the cleavage of the zygote of a Frog. A
cell has to go through the stages of the cell cycle to divide and produce new cells. A
single parent cell has the ability to create new cells and multiply its population and
hence the term cell cycle.
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What are the cell cycle phases?
The subsequent division of the cells known as the cell cycle involves the
photostatting of the genome and synthesis of the cell along with the division of the
cytoplasm. When talking about the human cell cycle, it displays the typical eukaryotic
cell cycle and takes 24 hours for the cessation of a single cycle of growth and
division. Such is the case with the human cell cycle whereas in the case of other
organisms the duration of the cell cycle varies.
The cell cycle of a typical eukaryotic is divided into two cell cycle phases :
Cell cycle phase: interphase or resting phase

3. Interphase or also known as the resting phase is the duration in which the cell
prepares for division by undertaking both cell growth and DNA multiplication. This
process alone takes 95% of the time of the entire cycle. The interphase stage of the
cell cycle is divided into the given three phases:
G1 phase (Gap 1):
The G-1 phase involves the duration of the cell wherein mitosis and initiation of
multiplication of the genetic material of the cell takes place.
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best?
S phase (Synthesis):
This phase involves the process of DNA replication. If the quality of the DNA of a cell
is shown as 2N then it will be considered 4N after the replication. Although, there
won't be any change in the number of chromosomes.
For example: if the quantity of the number of chromosomes is 2N then it will remain
so even at the end of the S phase. However, the centriole is divided into two
centriole pairs into the cells that contain the centriole.
G2 phase (Gap 2):
In this phase, the cells prepare themselves to enter the mitotic phase. This phase
involves the building of RNA, proteins, and other macromolecules required for the
replication of cell organelles, spindle formation, and cell growth. The bodies of adult
animals contain cardiac cells that are not subject to replication and the division takes
place only when there is a damaged cell or lost cell due to death. These cells do not
multiply further and acquire an inactive G0 phase which is also referred to as the
quiescent phase after the G1 phase is over. Such cells are metabolically active and
do not further divide unless the stated two situations take place.
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M Phase:

4. When the cell goes through an entire restructuring to procreate a progeny that has
the equivalent number of chromosomes as the parent cells is known as the mitotic
phase or the phase of the equational division. The other organelles also exhibit equal
division by the process of cytokinesis which is led up by mitotic nuclear division.
The mitotic phase is divided into given four stages:
● Prophase
● Metaphase
● Anaphase
● Telophase
● Mitosis
The process in which a eukaryotic cell parts the nuclear DNA and Chromosomes
and separates them into two varied but similar sets of nuclei are termed mitosis. As a
result of a mitotic spindle, the chromosomes are pulled apart. It is an esoteric
consisting of microtubules.
Cytokinesis
This phase involves the division of cytoplasm cells. This phase begins the moment
the mitosis stage ends. Due to the presence of high internal pressure and rigid cell
wall, plant cells are much firm than animal cells. Hence, this phase takes place
differently in animals and in plants.
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FAQs
What are the 5 major cell cycle phases?
The 5 major cell cycle phases are:
● Prometaphase
● metaphase

5. ● Anaphase
● Telophase
● Prophase
Who discovered the cell cycle?
The cell cycle was discovered by Walther Flemming in the 19th century.
Why is the division of cells important?
The division of cells is important due to the below-mentioned reasons: It supports
survival and promotes growth in organisms
Helps in balancing the number of chromosomes Creates new cells to replace the
damaged or dead ones.
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