Genetics and Cloning

Question 1

Mendel’s Law of Independent Assortment

Answer 1

Alleles of a particular gene are passed on to the offspring independently of each other during the formation of gametes

Question 2

Mendel’s Law of dominance

Answer 2

When two homozygous organisms with contrasting characteristics are crossed, all the individuals of the F1 generation will display the dominant trait.

An individual that is heterozygous for a particular characteristic will have the dominant trait as the phenotype.

Question 3

Mendel’s Principle of Segregation

Answer 3

An organism possesses two ‘factors’ (alleles) which separate or segregate so that each gamete contains only one of these ‘factors’ (alleles).

Half the gametes carry one allele, and the other half carry the other allele.

Question 4

Complete dominance

Answer 4

one allele is dominant and the other is recessive, such that the effect of the recessive allele is masked by the dominant allele in the heterozygous condition

Question 5

Incomplete dominance

Answer 5

neither one of the two alleles of a gene is dominant over the other, resulting in an intermediate phenotype in the heterozygous
condition

Question 6

Co-dominance

Answer 6

both alleles of a gene are equally dominant whereby both alleles express themselves in the phenotype in the heterozygous condition

Question 7

Harmful Mutations

Answer 7

change the DNA responsible for the production of a specific protein. This would cause changes to the organism’s physical appearance or functioning due to an incorrect/defective protein being made

Question 8

Harmless mutations

Answer 8

Mostly involve changes to the non-coding DNA (which makes up 98,5% of the DNA). This DNA is not involved in making proteins. It does not affect the structure or functioning of the cell/organism.

Question 9

Useful mutations

Answer 9

also change the DNA responsible for the production of a specific protein. If the protein made increases the organism’s chance of survival, it would be seen as a useful mutation

Question 10

Haemophilia

Answer 10

Haemophilia is the inability of the blood to clot due to a absence of blood clotting factors. If the sufferer were to cut themselves, the wound would continue to bleed until a clotting factor is transfused in a hospital.

Question 11

Process of cloning

Answer 11

Nucleus of an ovum is removed and replaced with the nucleus of a somatic donor cell
The zygote is stimulated for mitosis to occur
The embryo is then placed into the uterus of an adult female