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1. Introduction to Molecular
and Cellular Biology
Organisms require their cells to
divide for the purposes of
1. reproduction
2. growth,
3. development
4. or repair.
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2. Cellular division is divided into two
phases:
mitosis and cytokinesis.
Mitosis involves the division of the
nuclear chromosomes, while
cytokinesis is the division of the
cytoplasmic components into new
daughter cells.
Serious consequences, such as
cancer, can occur if this cell cycle is
disrupted in some way.
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Mitosis is the process
by which a cell
replicates its
chromosomes and
then segregates them,
producing two
identical nuclei in
preparation for cell
division.
Mitosis is generally
followed by equal
division of the cell's
content into two
daughter cells that
have identical
genomes.

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what is the main difference
between mitosis and meiosis?
What's the Difference?
Mitosis produces two genetically
identical “daughter” cells from a
single “parent” cell, whereas
meiosis produces cells that are
genetically unique from the parent
and contain only half as much
DNA.
Most cells in the body regularly go
through mitosis, but some do so
more often than others.

5. DNA and RNA
Molecular biology
Molecular biology is the branch of biology that
studies the molecular basis of biological
activity. In other words, it examines the
composition, structure, and interactions of
cellular molecules, such as nucleic acids (DNA
and RNA) and proteins, that carry out the
biological processes essential for a cell's
functions and maintenance.
is the study of subcellular structures, their
interactions, and how they function in the
biological processes of the cell.
In particular
nucleic acids are important molecules that
carry information that leads to the production
of proteins.
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6. molecular biology 6
Molecular biology research has
revolutionized our understanding of
life and has led to significant
advancements in various fields,
including medicine, biotechnology,
and agriculture. Here's a closer look
at some of the core areas of study
in molecular biology:

7. Proteins are the physical
expression of genetic information
in cells.
The nucleic acids deoxyribonucleic
acid (DNA) and ribonucleic acid
(RNA) are important molecules
that carry genetic information
throughout cells.
Like an architect’s blueprint,
nucleic acids have a set of rules
that lead to the synthesis of the
major building blocks of living
things.
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8. DNA and RNA
As their names indicate, deoxyribonucleic acid
(DNA) and ribonucleic acid (RNA) are both
nucleic acids. Any nucleic acid is a polymer
made up of monomers called nucleotides.
Any nucleotide consists of three components:
1.A pentose (five-carbon sugar)
2.A nitrogenous base attached to the pentose
3.A phosphate group also attached to the
pentose
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11. RNA also features four kinds of
nucleotides, and the nitrogenous
bases are nearly the same as for
DNA, except that RNA uses uracil
instead of thymine. DNA functions
for self-replication (before a cell
divides into two cells) and for
transcription, a process that
produces RNA.
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12. For DNA
, the specific pentose in each of its
nucleotides is deoxyribose,
whereas RNA features ribose as
the pentose in each of its
nucleotides.
There are normally four kinds of
DNA nucleotides because there are
four normal nitrogenous bases
used in DNA: adenine, guanine,
cytosine, and thymine.
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13. There are different functional
categories of RNA including mRNA,
tRNA, rRNA, and others.
Watch this overview of DNA and
RNA that explains how these
important nucleic acids form the
blueprint for life's structures.
After you watch, you should be
able to explain the difference
between RNA and DNA, identify
the three types of RNA, and discuss
the central dogma of how
information flows from gene to
protein.
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14. Nucleic acids are complex
molecules that store and transmit
hereditary information in living
organisms.
They are found in all cells and
viruses and are essential for life.
There are two main types of
nucleic acids: deoxyribonucleic
acid (DNA) and ribonucleic acid
(RNA).
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15. DNA is the genetic material that
contains the instructions for
building and maintaining an
organism. It is found in the nucleus
of cells and is made up of two long,
sugar-phosphate backbones linked
together by nitrogenous bases
. The nitrogenous bases are adenine
(A), guanine (G), cytosine (C), and
thymine (T). The order of these
bases in DNA determines the
genetic code.
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16. 1. Stores genetic information: DNA carries the instructions for
building and maintaining an organism, including its
physical characteristics and how its cells function.
2. Enables reproduction: DNA is passed down from parents to
offspring during reproduction, ensuring that the offspring
inherit the genetic information of their parents
3. Controls protein synthesis: DNA contains the instructions
for making proteins, which are essential for all cellular
processes.
4. Allows for evolution: Changes in the DNA sequence
(mutations) can lead to variations in organisms, which can
be beneficial or harmful. These variations can be passed
down to offspring, allowing for evolution over time.
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17. RNA is a shorter, single-stranded
molecule that plays a variety of
roles in the cell, including carrying
genetic information from DNA to
the ribosomes, where proteins are
made.
RNA is also involved in protein
synthesis, regulation of gene
expression, and other cellular
processes. There are three main
types of RNA: messenger RNA
(mRNA), ribosomal RNA (rRNA),
and transfer RNA (tRNA)
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18. Ribonucleic acid (RNA)
is a complex molecule essential
for various biological functions,
either directly performing the
function itself (non-coding
RNA) or by acting as an
intermediary between DNA and
protein production (messenger
RNA). RNA, along with
deoxyribonucleic acid (DNA),
belongs to a class of molecules
called nucleic acids.
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