Free Inheritance MCQs with Answers
1,238 Inheritance MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
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.
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- A. Erythroblastosis foetalis : X-linked
- B. Down's syndrome : 44 autosomes + XO
- C. Klinefelter's syndrome : 44 autosomes + XXY
- D. Colour blindness : Y-linked
Explanation: Klinefelter's syndrome is a genetic disorder in which there are three sex chromosomes, XXY, rather than the normal XX or XY.
Correct answer: Klinefelter's syndrome : 44 autosomes + XXY- A. 9 : 1
- B. 1 : 3
- C. 3 : 1
- D. 50 : 50
Explanation: Yellow (Y) seeds are dominant to green (y). So, a heterozygous yellow seeded plant will have the genotype of (Yy) and a green seeded plant…
Correct answer: 50 : 50- A. n = 21 and x = 21
- B. n = 21 and x= 14
- C. n = 21 and x = 7
- D. n = 7 and x = 21
Explanation: Hexaploid wheat is a result of allopolyploidy induced by doubling the chromosome number of the hybrid produced by crossing two different…
Correct answer: n = 21 and x = 7- A. Virus-related diseases
- B. Bacteria-related diseases
- C. Congenital disorders
- D. Pollutant-induced disorders
Explanation: A congenital disorder is a medical condition that is present at birth. Congenital disorders can be a result of genetic abnormalities, the…
Correct answer: Congenital disorders- A. All colour blind
- B. All normal visioned
- C. Onehalf colour blind and onehalf normal
- D. Threefourths colour blind and onefourth normal
Explanation: Colour blindness is a recessive sexlinked trait. Colour blindness is a recessive sexlinked trait.All sons will be colour blind and all…
Correct answer: All colour blind- A. Two
- B. Three
- C. Four
- D. Nine
Explanation: A plant with the genotype AABbCC will produce two different kinds of gametes.
Correct answer: Two- A. Genotype and environment interactions
- B. Mutations and linkages
- C. Cytoplasmic effects and nutrition
- D. Environmental changes and sexual dimorphism
Explanation: The phenotype of an organism is the observable physical and behavioural characteristics of an individual.
Correct answer: Genotype and environment interactions- A. Leucocytes
- B. Lymphocytes
- C. Platelets
- D. RBCs
Explanation: G-6-P (Glucose-6-Phosphate) dehydrogenase deficiency is an inherited genetic disorder that affects the red blood cells (RBCs).
Correct answer: RBCs- A. Cystic fibrosis
- B. Thalassaemia
- C. Haemophilia
- D. Cretinism
Explanation: Cretinism is not a hereditary disease; it is a condition related to severe congenital hypothyroidism, often caused by iodine deficiency…
Correct answer: Cretinism- A. 25% will be tall with red fruit
- B. 50% will be tall with red fruit
- C. 75% will be tall with red fruit
- D. All the offspring will be tall with red fruit
Explanation: When a plant with the genotype RRTt (red fruit and tall) is crossed with a plant that is rrtt (yellow fruit and short), the Punnett square…
Correct answer: 50% will be tall with red fruit- A. One-third of the progenies
- B. None of the progenies
- C. All the progenies
- D. Fifty percent of the progenies
Explanation: When one of the parents in a cross has a mutation in its mitochondria and is considered the male, the mutation is usually found in none of…
Correct answer: None of the progenies- A. Lethal
- B. Sublethal
- C. Expressed in males
- D. Expressed in females
Explanation: The correct answer depends on the specific context or terminology used.
Correct answer: Expressed in males- A. Axial flower position
- B. Green seed colour
- C. Green pod colour
- D. Round seed shape
Explanation: The recessive feature among the provided options that Mendel studied in garden pea plants was the green seed color (option b).
Correct answer: Green seed colour- A. Seven
- B. Six
- C. Five
- D. Four
Explanation: The genes controlling the seven pea characters studied by Mendel are now known to be located on four different chromosomes (option d).
Correct answer: Four- A. Test cross
- B. Reciprocal cross
- C. Dihybrid cross
- D. Reverse cross
Explanation: A test cross is used to determine the genotype of an individual with a dominant phenotype by crossing it with a known homozygous recessive…
Correct answer: Reciprocal cross- A. Sex linked traits
- B. Sex limited traits
- C. Sex influenced traits
- D. Sex determining traits
Explanation: Sex-linked traits are located on the sex chromosomes and are inherited differently in males and females.
Correct answer: Sex influenced traits- A. Thalassaemia
- B. Sickle cell anaemia
- C. Pernicious anaemia
- D. Leukaemia
Explanation: Thalassemia is a genetic blood disorder but is not associated with protection from mosquito-borne diseases.
Correct answer: Sickle cell anaemia- A. 100 %
- B. 75 %
- C. 50 %
- D. 25 %
Explanation: Down syndrome is caused by an extra copy of chromosome 21 (trisomy 21).
Correct answer: 50 %- A. The ratio of number of X-chromosome to the sets of autosomes
- B. X and Y chromosomes
- C. The ratio of pairs of X-chromosomes to the pairs of autosomes
- D. Whether the egg is fertilized or develops parthenogenetically
Explanation: In Drosophila, the sex determination mechanism involves the X/A ratio, where a specific ratio of X-chromosomes to autosomes determines the…
Correct answer: The ratio of pairs of X-chromosomes to the pairs of autosomes- A. Haemophilia
- B. Thalassemia
- C. Sickle cell anaemia
- D. Colour blindness
Explanation: Pleiotropy refers to the phenomenon where a single gene has multiple effects on an organism's phenotype. Among the options provided, "c.
Correct answer: Sickle cell anaemia