AssignmentNo 2Bio301MC170404186Questionno 1: Differentiate between somatic and germline mutation? Give at least twoexamples of each?Answer: Somatic mutation Germ line mutation 1.
The mutations which occur in the somatic cells are called the somatic mutations. The mutations which occur in the cells that produce gametes are called germline mutations. 2. These mutations cannot pass from the parents to offspring. These mutations can pass from parents to offspring. it can pass from one generation to another generation. 3. These mutations occur during the type of cell division which is called the mitosis.
These mutations occur during the meiosis which is also a type of cell division. 4. 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. 5. When this mutation occur the number of cells which have mutated gene depends on the stage of cell division. In this mutation, During the embryo stage all cells have effects of germ line mutation. 6.
Example: Coat’s disease occurs due to this type of mutations. Cancer also developed due to this mutation Hemophilia, porphyria and sickle cell anemia are the examples of germline mutation. Questionno2: Write a note on spontaneous and induced mutations?Answer:Spontaneous mutations: Spontaneous mutationsare those mutations which develop duo to the natural changes in the DNA. Theorigin of this type of mutation is unknown. They arise duo to the action ofcertain mutagenic agents which are present in the environment.
These are causedue to mutagenic chemicals. Those chemicals can be Cosmic rays. They can beheat, radioactive compounds and naturally occurring base analogs. Inducedmutations:Induced mutations are those mutations which areartificially produced in the DNA of the living organisms. These are produced byexposing the organisms to abnormal environment such as radiation and physical conditions.For example, temperature.There are certain agents which induced artificialmutations in the organisms are called mutagensor 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 ethyleneamine, colchicines and ethyl -methyl sulphonate.These chemicals are used to producemutations in the organisms or cells.In addition to these chemicals there are certainbases analogous.
These are similar to the normal nucleotides or the normalbases. DNA polymerases cannot distinguish between the normal base and baseanalogs. These base analogs can be incorporated into newly synthesized DNAmolecules.