no 1: Differentiate between somatic and germline mutation? Give at least two
examples of each?
Germ line mutation
The mutations which occur in the somatic cells are
called the somatic mutations.
mutations which occur in the cells that produce gametes are called germline
These mutations cannot pass from the parents to
These mutations can pass from parents to offspring.
it can pass from one generation to another generation.
These mutations occur during the type of cell
division which is called the mitosis.
mutations occur during the meiosis which is also a type of cell division.
When changes occur in the DNA of the somatic cells
then the somatic mutations occur. For example these occur in the cells of
eyes skin and liver etc.
When the changes occur in the DNA of the
germ cells then the germ line mutation occurs. These exist in the oogonia in
females and spermatogonia in female.
When this mutation occur the number of cells which
have mutated gene depends on the stage of cell division.
this mutation, During the embryo stage all cells have effects of germ line
Example: Coat’s disease occurs due to this type of
Cancer also developed due to this
porphyria and sickle cell anemia are the examples of germline mutation.
no2: Write a note on spontaneous and induced mutations?
are those mutations which develop duo to the natural changes in the DNA. The
origin of this type of mutation is unknown. They arise duo to the action of
certain mutagenic agents which are present in the environment. These are cause
due to mutagenic chemicals. Those chemicals can be Cosmic rays. They can be
heat, radioactive compounds and naturally occurring base analogs.
Induced mutations are those mutations which are
artificially produced in the DNA of the living organisms. These are produced by
exposing the organisms to abnormal environment such as radiation and physical conditions.
For example, temperature.
There are certain agents which induced artificial
mutations in the organisms are called mutagens
or mutagenic agents. These can be physical agents like X-rays,
UV rays, alpha, beta and gamma rays.
There are some chemical agents like mustard gas ethylene
amine, colchicines and ethyl -methyl sulphonate.These chemicals are used to produce
mutations in the organisms or cells.
In addition to these chemicals there are certain
bases analogous. These are similar to the normal nucleotides or the normal
bases. DNA polymerases cannot distinguish between the normal base and base
analogs. These base analogs can be incorporated into newly synthesized DNA