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Genetics is the study of heredity. Heredity is a biological process where a parent passes certain genes onto their children or

offspring. Every child inherits genes from both of their biological parents and these genes in turn express specific traits.

Some of these traits may be physical for example hair and eye color and skin color etc

Gene a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of theoffspring.

Chromosomes a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic

information in the form of genes

DNA deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of

chromosomes. It is the carrier of genetic information.

Mitosis a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as

the parent nucleus, typical of ordinary tissue growth.

Meiosis a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent

cell, as in the production of gametes and plant spores.

1.

The cell cycle can be separated into two major phases that alternate with each other: interphase,during which

the cell grows, prepares for mitosis and duplicates its DNA, and the mitotic (M) phase,in which the cell divides

into two genetically identical daughter cells

Interphase is divided into three phases: G 1, S, and G2. The subsequent mitotic (M) phase consists of two processes:

mitosis, the process of nuclear division, and cytokinesis, division of the cell's cytoplasm. Each mitotic phase results

in the formation of two cells that are genetically identical to the parent. The activation of each phase is dependent

on completion of the previous phase. Some cells divide continuously, while others can exit the active cell cycletemporarily or indefinitely by entering G0phase, where they stop dividing.

2. G1 Phase (the first Gap Phase):the first Stage of Interphase

During the G1 phase or the Gap 1 phase, the protein synthesis and the RNA synthesis within the cell resumes that was

interrupted during the process of mitosis. Growth and young cell maturation occurs, which accomplish the physiological

function. G1 phase is the phase during which the cell cycle starts with the synthesis of RNA and proteins required by the

young cells for their growth and maturity. The time period of the G1 phase of the interphase is varied highly among the

different species eukaryotic cells. For example, faster renovation tissues like the mucosa and the endometrial epithelium

require very short G1 periods as compared to the muscles or connective tissues that do not require frequent repair or

renovation. G1 phase is usually termed as the prior to DNA synthesis phase.

S Phase: the Second Stage of Interphase

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S phase:The DNA synthesis place as the name suggests, S which stands for synthesis. Soon after the G1 phase, DNA

checking and subsequent repair occurs during the variable pause phase before the transition of the cell cycle to the S

phase. The S phase of the interphase deals with the semi-conservative synthesis of DNA occurs. Replication of cellular DNA

begins with the S phase, which when gets duplicated with the cell containing nearly double the amount of chromosomes,

the cells from the S phase move into the G2 phase.

G2 Phase (the Second Gap Phase): the third Stage of Interphase

During the G2 phase, there is an increase in the synthesis of the RNA and the protein, which is followed by another round of

proof reading and subsequent repair among the newly synthesized DNA sequences before the cell cycle transits to the

mitotic cycle. The mitotic spindle formed from the cytokinetic fibers start forming and the cell ensures the number of

chromosomes and the organelles present, which further leads the cell cycle from the interphase to the mitotic phase.

3. Mitosis is a five stage process that results in diploid daughter cells which are genetically identical to the parent cell.

a. Interphase: The first stage, in which the DNA begins to divide within the nucleus.

b. Prophase: The second stage, in which the chromosomes become visible, the nucleus dissolves, and centrioles form and

move to opposite ends of the cell.

c. Metaphase: The third stage, in which the chromosomes line up in the center of the cell in a body called a centromere,

while spindle fibers form attached to the centrioles.

d. Anaphase: The fourth stage, in which the centromeres divide, separating each strand of chromosome into two, which are

pulled to opposite ends of the cell by the spindle fibers and centrioles.

e. Telophase: The fifth stage, in which the nuclear membrane and nucleus reforms around the chromosomes, and the cell isready to complete cell division.