1. James Watson and Francis Crick discovered the double helical structure of DNA in 1953. 2. Barbara McClintock discovered mobile genetic elements in maize plants in 1965, which helped establish the concept of jumping genes. 3. Genetic diseases like sickle cell anemia, thalassemia, albinism and Huntington's chorea are caused by defects in genes and result in characteristic symptoms. Protein models help understand protein structure and function.

1. MODERN GENITICS

2. James D. Watson
Francis Crick
Discovered
double helical
DNA

4. What is karyogram?
Karyotyping is a technique through which the complete set
of chromosomes are lined up. This chromosomal line is
termed as Karyogram.

7. GENETIC ENGINEERING
( RECOMbINaNT DNa
TEChNOlOGy )

12. Proteins are
linear
chain
Molecules
made
up of units
called
amino
acids

13. The existence of mobile genetic
elements (Transposons )
had been visualized by the geneticist
Barbara Meclintock
in her work in
Zea mays
in 1965

14. BARBARA
MECLINTOCK
Discovered mobile
genetic elements in
1965 on maize plant.

15. What is pedigree chart? (3 marks)
pedigree chart defines the history of a
character in a family.
It is also called family tree
It helps to identify and visualize the
course of genetic diseases in the
progeny.

16. baby with
Phenylketonuria

17. Phenylketonuria
pedigree chart

20. What are super bugs? Mention any one use of them.(3 marks)
1.Genetically Engineered bacteria are called super bugs. Eg.
Pseudomonas putida.
2. Super bugs produced first by an Indian researcher Anand
Chakravarthy in U.S.A.
3. It can destroy octanes, xylenes, camphor and toluene.

21. Pseudomonas putida

22. Pseudomonas
bacterium (Superbug)
Used to synthesize
Drugs ,antibiotics and
Hormones.

23. Write about the structure of
haemoglobin molecule.
1.The haemoglobin consists of
four sub units namely
2 alpha and 2 beta chains.
2. Each sub unit has an iron containing
molecule called Haeme and
a protein compound called globin.

27. Genetic diseases

37. Write the symptoms of sickle cell
anemia.
1.Abnormal hemoglobin's HbS
HbS
are
produced.
2.Fatal hemolytic anemia is occurred.
3.Damaged heart, kidney, spleen and brain
are resulted due to vascular obstruction.

39. Thalassemia
is a blood disorder passed down
through families (inherited) in which
the body makes an abnormal form of
hemoglobin, the protein in red blood
cells that carries oxygen. The disorder
results in excessive destruction of red
blood cells, which leads to anemia.

44. What are the symptoms of the
disease Thalassemia?
The clinical manifestations of
Thalassemia include
Decrease in the bone marrow activity.
Peripheral haemolysis.
Splenomegaly (enlarged spleen ) and
hepatomegaly( enlarged liver) etc.

47. What is albinism? Mention its characteristics
(for 3 marks)
It is an inherited disorder of melanin metabolism
characterized by the absence of melanin in the skin,
hairs and eyes.
The clinical characteristics of this disease are milk-
white coloured skin and marked photophobia.

50. Give an account of Albinism
It is an inherited disorder of melanin metabolism
characterized by the absence of melanin
in the skin ,hairs and eyes.
Clinical character
Milk white coloured skin
Marked photophobia
The metabolism one amino acid ,Phenylalanine
proceeds in chains of enzyme –mediated reactions
the change or absence of enzyme due to defective
gene, results in physiological abnormalities
complete lack melanin pigment causes Albino to
suffer

51. The albinism
in human has been reported to be from
1 : 5000 to 1 : 25000.
the albinism may be
generalized albinism of the eye (occular
albinism)
or partial albinism (skin and hair)
The recessive gene ‘ a a’ do not produce the
tyrosinase enzyme which converts
DOPA –(3,4-Dihydroxy phenyl alanine )
into melanin in the melanocytes

52. Localized albnism
Ocular albinism
Partial albinism
(skin and hair)

53. photophobia

55. Write note on “Bubble Boy Syndrome”
Severe combined Immunodeficiency (SCID) is
also called Bubble Boy Syndrome.
This is an extremely rare inherited disease
affecting children due to Adenine Deaminase
(ADA) gene present in chromosome 20
The affected child is to be kept in a sterile bubble.
The children suffering from the syndrome
completely lack the immune defense mechanism
against infection

57. What is Huntington’s Chorea? Mention its characteristics
( for three marks)
1.Huntington’s Chorea is a fatal disease
caused by an autosomal dominant gene in
humans.
2.It is characterized by uncontrolled jerking of the body,
deterioration of intellectual faculty, depression,
occasional hallucination and delusions and other
psychological problems.

58. Write short notes on Huntington’s chorea ( for 5 marks)
This is a fatal disease caused by an autosomal dominant
gene in human
onset of disease is between 35 and 45 years of age
it is characterized by uncontrolled jerking of body due to
involuntary twitching of voluntary muscles.
It leads to progressive degeneration of the central nervous
system accompanied by gradual mental and physical
deterioration.
Huntington’s disease was the first completely dominant
human genetic disease
the affected gene is located on chromosome 4
the other characteristics of this disease are deterioration of
intellectual faculty, depression , occasional hallucination
and delusions and other psychological problem.
This disease is incurable

63. Write the uses of protein model.
1.Protein structure helps in understanding biomolecular
arrangement in tissue or cellular architecture .
2.Protein structures, protein models and computer aided
graphic models help to understand biological reactions
mediated by enzymes (proteins)
3.Graphic models provided by computers are valuable to
predict which fragments of a medically important protein
can be used to design drugs and vaccines.
4.Proteomics also helps in chemical industries to
manufacture drugs, various chemical compounds and
enzymes.

71. What is known as glowing coal model?
(3 Marks)
1.The computer – generated models depict the
properties of amino acids in a protein and also
to
2. help to understand the protein function.
3.One of the computer graphic model is the
“Glowing coal” model.