Question

4: Units of inheritance known as genes exist in pairs.

Answer 1

Answer:

4. a

5. a

6. a

7. a

8. a

9. a

10. True

Explanation:

4. Units of inheritance in living organisms are known as genes. These genes exist in pairs in all organisms and a copy of each gene is passed down to the offspring during reproduction.

Correct option: a

5. Assuming the dominance of allele A over allele a:

                AA    x    aa

          Aa    Aa    Aa    Aa

All the offspring will appear tall since the effects of allele a is masked by allele A.

Correct option: a

6. From the cross in (5) above, the genotypic ratio of the offspring is 100% Aa.

Correct option: a

7. Alternate forms of genes in living organisms are known as alleles. A copy of the alleles is usually passed down to the offspring during the process of reproduction.

Correct option: a

8. Phenotypes are the physical appearance of organisms. They are physical interpretation of genes.

Correct option: a

9. The law of segregation was postulated by Gregor Mendel. It states that gene pairs segregate during the process of meiosis and then randomly unite during the process of fertilization.

Correct option: a

10 Heterozygous organisms have two different alleles for the same genes. For genes that obey Mendelian laws, heterozygous condition is characterized by one dominant and one recessive alleles.