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Difference between Cytokinesis and Karyokinesis

Science is a varied branch of knowledge consisting of three significant subjects, i.e., physics, biology, and chemistry. These three are different in their own sense. For instance, physics deals with gravitation, inertia, kinetics, force, etc., while chemistry deals with chemical compounds, reactions, formulas, periodic tables, etc. Biology is also completely different from them as it deals with plants, animals, and humans. Human beings and their related systems, animals, food chain, plants, chlorophyll, photosynthesis, etc., comes under biology. Biology is a vast subject dealing with the living things of nature. Now, two terms in biology carry great significance, i.e., cytokinesis and karyokinesis. Both these terms are related to cell structure and division. You must be wondering the definition of these terms. So, let us begin by understanding the meaning of cytokinesis and karyokinesis, followed by the difference between the two.

Cytokinesis

Cytokinesis is defined as the process of cell division at the end of meiosis. This process is responsible for bringing the division into the two daughter cells. In biology, cytokinesis is defined as the cytoplasmic division of cell of a eukaryotic cell. The cell division starts after the nuclear division of meiosis. The organelles, cytoplasm, and chromosomes are parted equally in the daughter cells. After the separation of the duplicate genome, cell division happens. Cytokinesis is of two kinds, i.e., symmetrical and asymmetrical. For instance, spermatogenesis is symmetrical cytokinesis as the cells are equal in content and size.

On the other hand, biogenesis is asymmetrical cytokinesis as the cells are not divided equally. Moreover, in asymmetrical cytokinesis, a large cell is produced having three polar bodies. Now, when does cytokinesis happen? Well, cytokinesis starts in anaphase (for animals) and prophase (for plants) and culminates at telophase. This process forms the two daughter cells through mitosis. Cytokineses is one of the crucial processes in both plants and animals as cell division is essential to take place. Therefore, the nucleus needs to end up in both the daughter cells during the separation process. There are two significant types of cytokinesis, i.e., the cell plate formation in plants and the embryonic cleavage in animals. Apart from the types, cytokinesis has five stages to begin, i.e., initiation, membrane, completion, contraction, and insertion. For initiating the cell division, the separation needs to take place at the right time.

Karyokinesis

Karyokinesis is quite different from cytokinesis. It is defined as the process of cell division occurring during mitosis. Karyokinesis is the primary step that leads to cytokinesis, i.e., karyokinesis is the process of cell division during mitosis, which further leads to the division of cytoplasm called as cytokinesis. In biology, the segregation of the nucleus in the daughter cells is known as karyokinesis. The karyokinesis is initiated in prophase, wherein the material divides itself equally into two halves. Karyokinesis happens in four significant stages, i.e., prophase, anaphase, metaphase, and telophase. Anaphase is the shortest phase of cell division, and telophase is the culmination of cell division. Now, cell division either happens through meiosis or mitosis. The new cells are formed and are divided later through mitosis or meiosis. Karyokinesis is essential for all living beings as every cell in the body rejuvenates and regenerates itself. This ensures the complete functioning of tissues and cells, which regenerates in a few hours. Now, there are some contrasting points between cytokinesis and karyokinesis. So, let us have a look at them.

S.NO.	CYTOKINESIS	KARYOKINESIS
1.	Cytokinesis is defined as the process of cell division that happens at the end of meiosis.	On the other hand, karyokinesis is defined as the process of cell division that happens during mitosis.
2.	There are five stages of cytokinesis. they are: Initiation Insertion Membrane Contraction Completion	There are four stages of karyokinesis. They are: Prophase Anaphase Metaphase Telophase
3.	Cytokinesis is the second step as it includes the division of the cytoplasm.	Karyokinesis is the first step and precedes cytokinesis.
4.	Cytokinesis is essential to happen as the cell division leads the nucleus in each daughter cell.	Karyokinesis is significant to happen as it leads to rejuvenation and regeneration of the cells after division.
5.	Cytokinesis is of two kinds, i.e., symmetrical cytokinesis and asymmetrical cytokinesis.	There is no such kind of karyokinesis.
6.	The cytoplasm divides the parent cell into two daughter cells.	The nucleus of the cell is divided into two daughter cells.
7.	Two daughter nuclei lead to the division of two daughter cells.	Chromosomes are divided into daughter nuclei.
8.	Cytoplasm and cellular material are equally divided.	The genetic material is equally divided.
9.	Cytokinesis is a simple process of cell division.	Karyokinesis is a relatively complex and sequential process involving the division of genetic material.
10.	The cell plate formation and embryonic cleavage take place in cytokinesis.	The movement of chromosomes and spindle formation takes place in karyokinesis.

So, these are some of the contrasting points between cytokinesis and karyokinesis. Now, there are certain characteristics associated with cytokinesis and karyokinesis. So, let us have a look at them.

Features of Cytokinesis

1. The cytokinesis happens at the end of meiosis and mitosis. This process helps in the division of daughter cells.
2. The formation of the contractile ring is the fundamental step of cytokinesis. This is how the process is initiated.
3. The contractile ring comprises of cytoskeleton proteins.
4. The plasma membrane is fused together and breaks after the contraction of the ring.
5. The daughter nuclei are opposite to one another. The cell is present in the middle.
6. The cell is equally divided, so much to that the nucleus is present in each daughter cell.
7. The cell plate formation takes place in plants, and embryonic cleavage happens in animals.

Features of Karyokinesis

1. The process of cell division during mitosis is called karyokinesis.
2. Karyokinesis is a primary step that occurs during cell division.
3. The regeneration of cells takes place in karyokinesis.
4. The tissues, organelles, and cells function properly under karyokinesis.
5. The genetic material is evenly divided so that each daughter cell has a nucleus in it.

So, these are some of the characteristics of cytokinesis and karyokinesis. Both these processes are essential for all living beings as cell division is important to happen. Furthermore, both cytokinesis and karyokinesis happen in plants, animals, and humans. Thus, both these processes are significant for life sustenance on earth.

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