Moderate

Pick out the correct statements. (1) Haemophilia is a sex­linked recessive disease. (2) Down's syndrome is due to aneuploidy. (3) Phenylketonuria is an autosomal recessive gene disorder. (4) Sickle cell anemia is an X-­linked recessive gene disorder.

Correct answer: B. (1), (2) and (3) are correct.

  • A. (1), (3) and (4) are correct.
  • B. (1), (2) and (3) are correct.
  • C. (1) and (4) are correct.
  • D. (2) and (4) are correct.

Explanation

Sickle-­cell anemia is an autosomal recessive genetic disorder. It can be transmitted from parents to the offspring when both partners are carriers of the gene (or heterozygous). Sickle cell anemia is a genetic condition that has an autosomal recessive inheritance pattern. This means that the condition isn't linked to the sex chromosomes. Someone must receive two copies of a recessive allele in order to have the condition.

Last updated

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.

Exams that ask Biology questions like this

Biology is on 6 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions