(a)(i) State Mendel’s laws of inheritance. (ii) State five applications of genetics in medicine. (iii)...
(a)(i) State Mendel’s laws of inheritance.
(ii) Statefive applications of genetics in medicine.
(iii) Statethree disadvantages of inbreeding.
(b)(i) What is evolution?
(ii) Distinguish between convergent evolution and divergent evolution.
Explanation
(a) (i) Mendel’s laws of inheritance
First law/law of segregation
States that a pair of alleles/genes of contrasting character; segregates during gamete formation so that only one allele/gene enters a single gamete.
Second law/law of independent assortment
States that of a pair of alleles/genes of contrasting character; segregates independently; and combines randomly/distribute itself; with either of another pair of alleles/ genes.
(ii) Applications of genetics in medicine
- Screening blood for transfusion;
- Determining paternity/ parentage;
- Marriage counseling for genetic disorders;
- Production of certain drugs/insulin;
- Sex selection in babies;
- Cloning of cells;
- Test-tube babies/ in-vitro fertilization;
- Organ transplant.
- Analysis of blood in crime detection.
(iii) Disadvantages of inbreeding
- Loss of reproductive vigor/potency;
- Susceptibility to disease;
- Limited gene pool/lack of varieties;
- Inability to withstand environmental changes;
- Replication /retention of undesirable traits.
(b) (i) Evolution
The process of development of complex organisms; from simple forms; over a long period of time; and results in the origin of new species.
(ii) Convergent and divergent evolution
Convergent evolution produces similar structures in organisms; that have evolved from different unrelated ancestors; while divergent evolution produces modification of structures in organisms that have evolved from a common ancestor; due to adaptation to environmental changes.