Cell Biology | Assignment | Doc

Running head: CELL BIOLOGY
CELL BIOLOGY
Name of the Student
Name of the University
Author Note

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Table of Contents
Section 1....................................................................................................................................2
Cell structure.........................................................................................................................2
Comparison table for prokaryotic and eukaryotic cells........................................................4
Eukaryotic subcellular organelle...........................................................................................5
Section 2....................................................................................................................................7
Role of cell membrane..........................................................................................................7
Use of nutrients by animal cells............................................................................................8
Role of nucleic acids...........................................................................................................10
Protein synthesis..................................................................................................................11
Section 3..................................................................................................................................12
Generation of specialised tissue..........................................................................................12
Role of interphase................................................................................................................13
Retrieval of genetic information by daughter cells.............................................................15
Cancer cells vs normal cells................................................................................................16
Recommendation.....................................................................................................................17
Conclusion...............................................................................................................................17
Bibliography............................................................................................................................18

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Section 1
Cell structure
The cell is the most basic functional and structural unit of any living organism. It is
also considered as the building blocks of life. There are quite a few functions or
characteristics that a living cell exhibits which include Cellular metabolism, Cellular
Reproduction or Growth, Homeostasis, Internal and External Movement of Cells and Use of
Energy in Cells (U.S. National Library of Medicine 2020).
Cellular metabolism is the most promising and significant characteristic living cell.
This process involves either the catabolism or the anabolism of the biomolecules which are
taken inside the living cells. These biomolecules are taken inside the living cell with the help
of either the active transport or passive transport. Membrane transporters have been found to
play a significant role in transporting molecules inside and out of the cells. The most
significant characteristic of a living cell which is associated with cellular metabolism is the
protein machinery which synthesizes enzymes. Enzymes are the most significant components
of all the metabolic canonical pathways. Some of the most significant metabolic processes are
glycolysis, Krebs cycle, amino acid, lipid and nucleic acid metabolism. All these metabolic
processes can only be performed by a living and viable cell. Metabolism either synthesises
energy when required by a cell or uses energy to perform works such as active transport by a
cell. Thus, it can be stated that cellular metabolism is an essential functional characteristic of
living cells. Other functional characteristics of cells include response to a specific stimuli and
grow by cell division. Cell growth will be later discussed along with mitosis and meiosis.
Cellular Reproduction or Growth is one of the most important character that cells exhibit.
The mode of reproduction the living cells follow is the cell division. By dividing one mother
cell, it becomes two daughter cells and thus the whole process continues throughout a living

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being’s life to replace the old cells in the body and also for enhancing the growth of tissue.
The two daughter cells resulted from the division of mother cell contains the same genetic
material as of the mother cell (Salazar-Roa. and Malumbres 2017).
Fig. 1: Cell Structure (Image retrieved from National Cancer Institute 2020)
Homeostasis is the second character that a cell exhibit by which the internal
environment of a cell is maintained. Cell membrane, a part of the cell helps in this process by
keeping certain substances inside the boundary and other substances outside the boundary as
required and thus keeps the cell in equilibrium. Homeostasis also regulates the water content,
pH, temperature and presence of electrolytes within the cell (Kotas and Medzhitov 2015).
Internal and External Movement is the next character that a cell shows. It is the ability
a cell has by which it can maintain the fluidity and flexibility of a cell. The internal
movement is the movement of cell constituents within the cell boundary (Strale et al. 2015).
The external movement helps the cell to stay in equilibrium during temperature change and
growth (Foldes-Papp 2015). These types of movements also aids in stabilising a cell.
Cells for performing all the functions to maintain the structure needs energy. Starting
from production of protein, proper functioning of the cell and cellular reproduction, each of
the phenomenon that takes place in the cell requires energy expenditure. The cells use

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Adenosine Triphosphate (ATP) and various types of sugar molecules as its energy source
(Garcia and Shaw 2017).
Comparison table for prokaryotic and eukaryotic cells
Difference between prokaryotic cells and eukaryotic cells include (Archibald 2015):
CHARACTER PROKARYOTIC CELL EUKARYOTIC CELL
DEFINITION Prokaryotes can be defined
as the organisms having only
one cell
Eukaryotes can be defined as
the organisms having more
than one cell
NUCLEUS Prokaryotic cells lack
nucleus.
Eukaryotic cells contain
nucleus.
CHROMOSOME NUMBER Contains one chromosome
and plasmids.
Contain more than one
chromosome and plasmids.
NUCLEUS MEMBRANE It is absent. It is absent.
Genetic Recombination Process include
unidirectional transfer of
DNA.
Process include meiosis and
gamete fusion.
CELL ORGANELLES Cell organelles are absent in
prokaryotic cells.
Cell organelles are present.
PLASMA MEMBRANE It is absent in prokaryotic
cells.
It is present in eukaryotic
cells.
CELL WALL It is present in prokaryotic
cells.
It is present in some
multicellular organisms and
others lack it.
CELL SIZE Varies from 1 μm to 10 μm. Varies from 10 μm to 100
μm.
EXAMPLES Bacteria and Archaea. Plants, Animals and Insects.
Table 1: Differences between Prokaryotic and Eukaryotic Cell
When a virus attacks a prokaryotic cell, there might be three consequences. In first
case, bacteria activate some mechanisms, and neutralizes the viral DNA and as a result
nothing would happen to the bacteria or the prokaryotic cell. In the second scenario, the viral
DNA enters the cell and synthesize necessary proteins using the machineries of the host cell
and then would break open the cell and the phage will exit the cell in huge numbers. This
process is known as Lytic infection. In the third scenario, the phage or virus DNA would
enter the cell and would integrate with the bacterial chromosome and continue growing.

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When required the virus would enter the lytic cycle and would break open the cell and exit.
This is known as Lysogeny infection (Erez et al. 2017).
When a virus attacks, a eukaryotic cell it can give rise to three consequences. In the
first case, when a virus attacks a cell, interferon is released and the adjacent cells are turned
antiviral thus preventing the spread of virus. In the second case, the viral DNA is
incorporated with the genome of the host forming virome which does not express. In the third
case, the viral DNA is incorporated with the genome of the host and expresses after a latency
(Ogilvie and Jones 2015)
Eukaryotic subcellular organelle
Fig. 2 (i): Lytic & Lysogeny Cycle (Image retrieved from Researchgate 2020)
The subcellular structure in eukaryotic cells includes plasma membrane, nuclear
membrane, cytoplasm, cell wall and different organelles. Plasma membrane is made up of
lipid bilayer and proteins embedded into it. It is the outer boundary which covers the entire
cell structure. Nuclear membrane is made up of lipid bilayers as well and it covers the genetic
material of the cell. In both the eukaryotes and prokaryotes, plasma membrane can be
identified as a covering of double lipid bilayer which can be observed a microscope.