Cell Biology: Mitosis, Meiosis, and Levels of Cell Organization

This article discusses the stages of mitosis and meiosis, their similarities and differences, and the different levels of cell organization. It also compares the levels of cell organization between arteries and small intestine.

Running head : CELL BIOLOGY
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CELL BIOLOGY
3.1a) the stage of mitosis
In cell biology, mitosis is part of the cell cycle when replicated chromosomes are
separated by two nuclei and give rise to genetically identified cells. Mitosis observed in all
somatic cells. Mitosis consists of four basic steps such as prophase, metaphase, anaphase, and
telophase. These stages occur in a strictly sequential manner (Bisson-Filho et al. 2017). In
prophase mitotic spindle forms and nucleus disappears whereas, In Metaphase, genetic materials
were duplicated. The process of cell division starts with anaphase (cytokinesis) and in
telophase, the genetic material separates carried in two identical daughter cells (Cai et al. 2017).
Figure: mitosis
Source: (Bisson-Filho et al. 2017).
b) The stages of meiosis:
Meiosis is a cell division occurred in reproductive cells where the chromosome numbers
reduced by half to create four haploids and each genetically distinct. There are two meiosis
stages where each stage divided into four basic steps like mitosis as discussed before (Bisson-
Filho et al. 2017). However, meiosis I include the crossing over whereas meiosis II is like the
mitosis.

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Figure: The stages of meiosis
Source : (Cai et al. 2017).
c) Similarities between
meiosis and mitosis:
Although diversity observed between meiosis and mitosis, both meiosis and meiosis
involve four distinct stages such as prophase, metaphase, anaphase, and telophase. The common
goal of both processes is that split the nucleus and DNA content in two daughter cells. Therefore,
both meiosis and mitosis involve in a similar pathway for accomplishing the process. Both
process are crucial for growth (Palazzo et al. 2016).
d) Difference between meiosis and mitosis:
differences Mitosis Meiosis
Cell Division A somatic cell divides once. A reproductive
cell divides twice
Daughter Cell Number Two diploid daughter cells
having same chromosome
Four haploid daughter cells
having one half number of
chromosome from parent
cells (Samuelson 2018).
Genetic Composition No crossing over occurs and
identical genetically matters
observed (Oomen et al.
Crossing over occurred and
therefore, recombination of

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2019). genetic material observed
tetrad Formation Does not occur Occurs in prophase
Time required Less More
4.1:
a) Different level of cell organisations:
In the biological system, the biological level of organization defined as the way living
things arranged from simple to most complex. There are five different levels of organization
observed in the human body which involves organelles, cells, tissues, organ, organ system, and
organism. An organelle is a tiny cellular structure which performs a specific function within cells
and it is embedded in the cytoplasm of prokaryotic and eukaryotic cells. Different organelles
give rise to cells which are the smallest level of organization in living cells. Different types of
cells together give rise to tissues. There are four types of tissues present in the body such as
connective tissues present in bone and blood, epithelial tissues present in skin and cell lining,
nerve tissues present in the nervous system and muscle tissues (Samuelson 2018).. Tissues
collected give rise to the organs in living tissue. 11 organ systems are present of the body which
involve integumentary, muscular, nervous, skeletal, circulatory, lymphatic, respiratory,
endocrine, excretory, reproductive and digestive(Palazzo et al. 2016). Although there are 11
organs are present, each organ system was divided on the basis of their unique function. This
organ system further gives produce the anatomy of an organism.
b) Level of cell organisation comparing arteries and small intestine:
Considering the five levels of the organization, small intestine and arteries are two organs
of human anatomy. Bensaddek Nicolas and Lamond (2019) highlighted that there are four level
of organisation observed in small intestine such as organelles, cells, tissues, organ. On the other
hand, the arteries have three different levels of cell organization such as organelles, cells, tissues.

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Considering the small intestine, mucosa of the small intestine is lined by a simple columnar
epithelium having absorptive cells, goblet cells and occasional enter endocrine cells. In crypts, it
includes the stem cells and paneth fells. In the small intestine, the sub mucosa composed of the
loose connective tissues, blood vessels, and dispersed lymphoid tissues, epithelial tissues. On the
other hand, considering arteries, it is the largest blood vessels consists of red blood cells,
endothelial cells, endothelium cells separated by a basal lamina. The function of the arteries is to
carry oxygenated blood away from the heart (Oliveira 2018). Considering the tissues present,
connected tissues are present in arteries .smooth endothelial cells are present in the arteries to
handle high pressure of blood flow in arteries.

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References:
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