Question

List three places outside of Africa where sickle-cell anemia is fairly common in the indigenous population:

Why hasn't the sickle-cell trait died out?

What is the ultimate source of biological variation?

What is the difference between gene flow and genetic drift?

Answer 1

Q.1. Three another places outside africa where sickle cell anemia is common are:- Nigeria, India, and prople republic of congo . In which disease affects two percent of population and the rate of carrier is high as 10 to 30 percent.  

Q.2 sickle cell trait not died out due to A. Associated with sudden death.

B. Exertional collapse in individuals.

C. Exercise collapse associated with sickle cell trait.

Q.3. Ultimate source of biological variation :- Random mutation of genetic variation because mutations are rare, neutral or deleterious. After that natural selection are adopted.

Q.4. Difference of gene flow and genetic drift :-

A. BASED ON DEFINITION :- GENE FLOW - it is process of transfer of alleles from one population to another.

Genetic drift :- in a gene pool there is alterations of alleles frequency.  

B. BASED ON CAUSED ON GENE ALTERATIONS :- Gene flow :- it caused isolation of migration or geographical.

Genetic drift :- bottle effect or founder effect for sampling.

BASED ON CAUSED ON MOVEMENT :-

GENE FLOW :- Breaking away few members and forming new member- founder effect.

Genetic drift :- Transferring of organism to population of already existing.

BASED ON CHANCES OF GENETIC VARIATION :-

GENE FLOW:- ensures genetic variation,  

Genetic variation :- less likely ensure genetic variation.