Learn about central dogma of mollecular

1. Central
Dogma of
Molecular
Biology

2. Introduction:
“Genetics - Central Dogma of Life”
http://www.youtube.com/watch?v=whV_CkKT7F0

3. The central dogma of
molecular biology states
that DNA contains
instructions for making a
protein, which are copied
by RNA. RNA then uses
the instructions to make a
protein. In short: DNA →
RNA → Protein, or DNA to
RNA to Protein
Central Dogma of Molecular Biology

4. 1.Replication : a double stranded
nucleic acid is duplicated to give
identical copies. This process
perpetuates the genetic
information.
2. Transcription : a DNA
segment that constitutes a gene is
read and transcribed into a single
stranded sequence of RNA. The
RNA moves from the nucleus into
the cytoplasm.
3. Translation : the RNA
sequence is translated into a
sequence of amino acids as the
protein is formed.

5. There are 4 different nucleotides :
• dATP : deoxyadenosine triphosphate
• dGTP : deoxyguanosine triphosphate
• dTTP : deoxythymidine triphosphate
• dCTP : deoxycytidine triphosphate

6. Figure2: From nucleotide to DNA.
DNA is formed by coupling the
nucleotides between the
phosphate group from a
nucleotide (which is positioned on
the 5th C-atom of the sugar
molecule) with the hydroxyl on the
3rd Catom on the sugar molecule
of the previous nucleotide. To
accomplish this, a diphosphate
molecule is split off (and releases
energy). This means that new
nucleotides are always added on the
3’ side of the chain.

7. Figure 3 : The DNA in a cell.
There are three types of genes :
1. Protein-coding genes : these
are transcribed into RNA and
then translated into proteins.
2. RNA-specifying genes : these
are only transcribed into RNA.
3. Regulatory genes : according to
a narrow definition, these include
only untranscribed sequences.
The first two types are also called
'structural genes'.

8. Protein Structure
1. Primary Structure
Primary proteins are unbranched polymers of amino acids linked head to
tail, from carboxyl group to amino group, through formation of covalent
peptide bonds, a type of amide linkage.
2. Secondary Structure
Structures resulting from these interactions constitute secondary structure for
proteins. When a number of hydrogen bonds form between portions of the
peptide chain in this manner, two basic types of structures can result α-
helices and β-pleated sheets.

9. Protein Structure (cont.)
3. Tertiary Structure
The folding of a single polypeptide chain in three-dimensional space is
referred to as its tertiary structure. All of the information needed to fold the
protein into its native tertiary structure is contained within the primary structure
of the peptide chain itself.
4.Quaternary Structure
Many proteins exist in nature as oligomers, complexes composed of (often
symmetric) noncovalent assemblies of two or more monomer subunits. The
way in which separate folded monomeric protein subunits associate to form
the oligomeric protein constitutes the quaternary structure of that protein

10. Biological Functions of Protein
1. Regulatory Proteins
A number of proteins can regulate the ability of other proteins
to carry out their physiological functions. (ex. insulin, the
hormone regulating glucose metabolism in animals)
2. Transport Proteins
A third class of proteins is the transport proteins. These proteins function to
transport specific substances from one place to another.
3. Storage Proteins
Proteins whose biological function is
to provide a reservoir of an essential nutrient are called storage proteins.
Because proteins are amino acid polymers and because nitrogen is commonly a
limiting nutrient for growth, organisms have exploited proteins as a means to
provide sufficient nitrogen in times of need.

11. Biological Functions of Protein (cont.)
4. Contractile and Motile Proteins
Certain proteins endow cells with unique capabilities for movement. Cell
division, muscle contraction, and cell motility represent some of the ways in
which cells execute motion.
5. Structural Proteins
An apparently passive but very important role of proteins is their function in
creating and maintaining biological structures. Structural proteins provide
strength and protection to cells and tissues.
6. Exotic Proteins
Some proteins display rather exotic functions that do
not quite fit the previous classifications. Monellin, a
protein found in an African plant, has a very sweet
taste and is being considered as an artificial sweetener
for human consumption.

12. Biological Functions of Protein (cont.)
7. GLYCOPROTEINS
Glycoproteins are proteins that contain carbohydrate. Proteins destined for
an extracellular location are characteristically glycoproteins.
8. LIPOPROTEINS
Blood plasma lipoproteins are prominent
examples of the class of proteins conjugated
with lipid. The plasma lipoproteins function
primarily in the transport of lipids to sites of
active membrane synthesis.
9. NUCLEOPROTEINS
Nucleoprotein conjugates have many roles in the storage and transmission
of genetic information. Ribosomes are the sites of protein synthesis.
Virus particles and even chromosomes are protein–nucleic acid complexes.

13. Biological Functions of Protein (cont.)
10. PHOSPHOPROTEINS.
These proteins have phosphate groups esterified
to the hydroxyls of serine, threonine, or tyrosine
residues. Casein, the major protein of milk,
contains many phosphates and serves to bring
essential phosphorus to the growing infant.
11. METALLOPROTEINS. Metalloproteins are either metal storage forms, as
in the case of ferritin, or enzymes in which the metal atom participates in a
catalytically important manner.
12. HEMOPROTEINS
These proteins are actually a subclass of metalloproteins because their
prosthetic group is heme, the name given to iron protoporphyrin IX.
13. FLAVOPROTEINS
Flavin is an essential substance for the activity of a number of important
oxidoreductases.

14. ---END---

15. Cell
Reproduction
and Genetics
A. Cell Division
1. Mitosis
2. Meiosis
B. Patterns of Inheritance
C. Mendel’s Laws of Heredity
D. Applications of Genetic
Engineering

16. Introduction:
The Cell Cycle (and cancer)
http://www.youtube.com/watch?v=QVCjdNxJreE

17. Cell division is a part of the cell cycle. The cell cycle is an orderly set of stages that take place between the time
a cell divides and the time the resulting cells also divide.
The Cell Cycle
The Stages of Interphase

18. The Cell Cycle
Apoptosis

19. Mitosis
“Mitosis: The Amazing Cell Process that Uses Division to Multiply!”
http://www.youtube.com/watch?v=f-ldPgEfAHI

20. Mitosis

21. Mitosis in animal cells

22. Mitosis in animal cells
Prophase. It is apparent during early prophase that cell division is about
to occur. The centrosomes begin moving away from each other toward
opposite ends of the nucleus. Spindle fibers appear between the
separating centrosomes as the nuclear envelope begins to fragment,
and the nucleolus begins to disappear.
Prometaphase. During prometaphase, preparations for sister
chromatid separation are evident. Kinetochores appear on each side
of the centromere, and these attach sister chromatids to the
kinetochore spindle fibers. These fibers extend from the poles to the
chromosomes, which will soon be located at the center of the spindle.
Metaphase. By the time of metaphase, the fully formed spindle
consists of poles, asters, and fibers. The metaphase plate is a plane
perpendicular to the axis of the spindle and equidistant from the poles.

23. Mitosis in animal cells
Anaphase. At the beginning of anaphase, the centromeres uniting the sister
chromatids divide. Then the sister chromatids separate, becoming daughter
chromosomes that move toward the opposite poles of the spindle. Daughter
chromosomes have a centromere and a single chromatid.
Telophase. During telophase, the spindle disappears, and nuclear envelope
components reassemble around the daughter chromosomes. Each daughter
nucleus contains the same number and kinds of chromosomes as the original
parental cell. Remnants of the polar spindle fibers are still visible between the
two nuclei.

24. Mitosis in Plant Cells

25. “Meiosis”
http://www.youtube.com/watch?v=VzDMG7ke69g

28. Meiosis, which requires two nuclear divisions, results in
four daughter nuclei, each having one of each kind of
chromosome and therefore half the number of
chromosomes as the parental cell.
First Division:

29. First Division:

30. First Division:

31. Second Division:

32. Second Division:

33. Comparison of Meiosis
with Mitosis

34. Comparison of Meiosis with Mitosis

35. Father Mother
The Human Life Cycle
Spermatogenesis and Oogenesis in
Humans
In human males, meiosis is a part of
spermatogenesis, which occurs in the
testes and produces sperm. In human
females, meiosis is a part of oogenesis,
which occurs in the ovaries and produces
eggs.

36. “Human Life Cycle”
http://www.youtube.com/watch?v=7646b5Ee7BE

37. Mendel’s Laws of Heredity
Why we look the way we look...

38. What is heredity?
● The passing on of characteristics
(traits) from parents to offspring
● Genetics is the study of heredity.

39. Studying genetics...
● More than 150 years ago, an Austrian monk
named Johann Gregor Mendel observed that pea
plants in his garden had different forms of
certain characteristics.
● Mendel studied the characteristics of pea
plants, such as seed color and flower color
Developed the law of inheritance, which is
now called as Mendel’s Principles
●

40. Mendel used peas...
● They reproduce
sexually
● They have two
distinct, male and
female, sex cells
called gametes
● Their traits are
easy to isolate

41. Mendel crossed them
● Fertilization - the uniting of male and female
gametes
● Cross - combining gametes from parents with
different traits

42. What Did Mendel Find?
● He discovered different laws and rules that explainfactors
affecting heredity.

43. Rule of Unit Factors
● Each organism has two alleles for each trait
Alleles - different forms of the same gene
Genes - located on chromosomes, they
control how an organism develops

44. Phenotype & Genotype
● Phenotype - the way an organism looks
– red hair or brown hair
● Genotype - the gene combination of an
organism
– AAor Aa or aa

45. Heterozygous & Homozygous
● Heterozygous - if the two alleles for a trait are different (Aa)
● Homozygous - if the two alleles for a trait are the same (AA or aa)

46. Rule of Dominance
● The trait that is observed in the offspring is
the DOMINANT trait (UPPERCASE)
● The trait that disappears in the offspring is
the recessive trait (lowercase)
“In a cross of parents that are pure for
contrasting traits, only one form of the trait will
appear in the next generation. Offspring that are
hybrid for a trait will have only the dominant trait
in the phenotype.”

47. Law of Segregation
● The two alleles for a trait must
separate when gametes are formed
● A parent randomly passes only one
allele for each trait to each offspring
“During the formation of gamete, each
gene separates from each other so
that each gamete carries only one
allele for each gene.”

48. Law of Independent Assortment
● The genes for different traits are inherited independently of each
other.

49. https://www.youtube.com/watch?v=Mehz7tCxjSE

50. Applications of Genetic Engineering
In Medicine: Genetic engineering can be applied to:
• Manufacturing of drugs
• Creation of model animals that mimic human conditions and,
• Gene therapy
• Human growth hormones
• Monoclonal antibodies
• Vaccines

51. Applications of Genetic Engineering
In Research:
Genes and other genetic information from a wide range of
organisms can be inserted into bacteria for storage and
modification, creating genetically modified bacteria in the process.
In Industry:
Transformation of cells in organisms with a gene coding to get a
useful protein.

52. Applications of Genetic Engineering
In Agriculture:
• Genetically modified crops are produced using genetic
engineering in agriculture.
• Such crops are produced that provide protection from insect
pests.
• It is used or can be used in the creation of fungal and virus-
resistant crops.
Genetic engineering can be applied to other areas:
• Conservation
• Natural area management
• Microbial art

53. --END--

54. Biotechnology
and Bioethics

55. DNA Technology
Genome - the complete genetic makeup of
an organism
Genetic engineering – a practice that has
innumerable uses, from producing a product
to treating cancer and genetic disorders
Gene cloning - Another major biological application of cloning which is the production of
many identical copies of a single gene.
Transgenic organisms - organisms with foreign DNA or genes inserted into bacterium,
plant or animal

56. Recombinant DNA Technology
Recombinant DNA (rDNA) contains DNA from two or
more different sources, such as the human cell and the
bacterial cell in the figure.
Vector - a piece of DNA that can be manipulated such that
foreign DNA can be added to it
Plasmids - small accessory rings of DNA from bacteria that
are not part of the Bacterial chromosome and are capable
of self-replicating.
Two enzymes are needed to introduce foreign DNA into Vector
DNA:
(1) a restriction enzyme to cleave the vector DNA
(2) DNA ligase to seal DNA into an opening created by the
restriction enzyme

57. DNA Analysis
DNA fingerprint – when a smaller fragments move farther
through the gel than larger fragments, and result in a pattern
of distinctive bands.
Short tandem repeat (STR) - are the same short sequence of
DNA bases that recur several times, STR profiling is
advantageous because it doesn’t require the use of restriction
enzymes

58. Biotechnology Products
Genetically modified organisms (GMOs)
- transgenic bacteria, plants, and animals
Biotechnology - products produced by GMOs.
Transgenic Bacteria
- Recombinant DNA technology is used to produce
transgenic bacteria, which are grown in huge vats
called bioreactors.
- have also been engineered to promote the health
of plants, extract minerals, and produce medically
important chemicals.

59. Transgenic Plants
- engineered to resist herbicides and pests, are commercially available.
- Techniques have been developed to introduce foreign genes into immature
plant embryos or into plant cells called protoplasts that have had their cell
wall removed. It is possible to treat protoplasts with an electric current while they
are suspended in a liquid containing
foreign DNA.
Transgenic Animals
- have been given various genes, in particular the one for bovine growth
hormone (BGH). Cloning of whole animals is now possible.
-Techniques have been developed to insert genes into the eggs of animals. It
is possible to microinject foreign genes into eggs by hand, but another
method uses vortex mixing. The eggs are placed in an agitator with DNA
and silicon-carbide needles.

60. Gene Therapy
is the insertion of genetic material into human cells
for the treatment of genetic disorders and various
other human illnesses, such as cardiovascular
disease and cancer.

61. The figure describes an ex vivo methodology for treating children who have SCID (severe combined
immunodeficiency). These children lack the enzyme ADA (adenosine deaminase), which is involved
in the maturation of T and B cells. Therefore, these children are prone to constant infections and
may die without treatment.
Ex Vivo Gene Therapy

62. In Vivo Gene Therapy
- In gene therapy trials, the gene needed to cure cystic fibrosis is sprayed into
the nose or delivered to the lower respiratory tract by an adenovirus vector or
by using liposomes. So far, these treatments have met with limited success, but
investigators are trying to improve uptake by using a combination of different
vectors.

63. Proteomics
- the study of which genes are active in producing proteins in which cells and under
which circumstances.
- the use of computers to assist with analysis of
data from proteomics and functional and
comparative genomics.
Bioinformatics

64. https://www.youtube.com/watch?v=cY-7gwnWESk
BIOETHICS
INTRODUCTION:

65. Bioethics
It is the study of ethical, social, and legal issues
that arise in biomedicine and biomedical research.
Bioethics includes:
1.Medical Ethics - focuses on issues in health care
2.Research Ethics - focuses issues in the conduct of research
3.Environmental Ethics – focuses in relationship between
human activities and the environment
4.Public Health Ethics - addresses ethical issues in public
health

66. PRINCIPLES OF BIOETHICS
1. PRINCIPLE OF AUTONOMY
• A person should be free to perform whatever action he/she wishes,
regardless of risks or foolishness as perceived by others, provided it
does not impinge on the autonomy of others

67. 2. PRINCIPLE OF BENEFICENCE
• One should render positive assistance to others [and abstain from
harm (minimalist principle of nonmaleficence) by helping them to
achieve benefits which will further their important and legitimate
interests
• Harm principle as a form of beneficence
- Prevent an individual from harming another

68. 3. PRINCIPLE OF JUSTICE
• One should give to persons what they are owed, what they deserve, or
what they can legitimately claim, treating equals equally unless there is A
morally relevant difference requiring persons to be treated
unequally/differently; consideration must often be given to A proper
allocation of benefits and burdens within the social context

69. 4. PRINCIPLE OF PARENTALISM
• One should restrict an individual’s chosen action against his/her consent in
order to prevent that individual from self-harm, or to secure for that
individual a good which he/she might not otherwise achieve
FORMS OF PARENTALISM
a. Strong Parentalism - restrict the liberty of those who are functionally
autonomous
b. Weak Parentalism - restrict the actions of those with permanent severely
diminished autonomy

70. ---END---