A polygenic inheritance in human beings is
Correct answer: A. Skin colour
- A. Skin colour
- B. Phenylketonuria
- C. Colour blindness
- D. Sickle cell anaemia.
Explanation
Polygenic (or Quantitative) inheritance is that type of inheritance in which the complete expression of a trait is controlled by two or more genes in which a dominant allele of each gene contributes only a unit fraction of the trait and total phenotypic expression is the sum total of a additive or cumulative effect of all the dominant alleles of genes/polygenes. Human skin color is an example of such polygenic inheritance which is controlled by three pairs of polygenes A, B and C. Negro/black color is due to presence of all the six dominant contributing alleles AABBCC. Very light color or white color is due to presence of all six recessive non-contributing alleles aabbcc.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Inheritance
Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.
Practise Inheritance
1,238 free Inheritance MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Biology questions like this
Biology is on 8 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Inheritance questions
Two dominant nonallelic genes are 50 map units apart. The linkage is:
Of a normal couple, half the sons are hemophiliac while half the daughters are carriers. The gene is located on:
Mr. Kapoor has Bb autosomal gene pair and d allele sexlinked. What shall be proportion of Bd in sperms?
Mendel studied inheritance of seven pairs of traits in Pea which can have 21 possible combinations. If you are told that in one of these combinations, independent assortment is not observed in later studies, your reaction will be:
Sex is determined in human beings:
A child of O-group has B-group father. The genotype of father will be: