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. Between two genotypes with recessive trait
- B. Between two F1 hybrids
- C. The F1 hybrid with a double recessive genotype
- D. Between two genotypes with dominant trait
Explanation: A test cross is a genetic cross performed to determine the genotype of an organism exhibiting a dominant phenotype.
Correct answer: The F1 hybrid with a double recessive genotype- A. Tightly linked genes on the same chromosome show higher recombinations
- B. Genes far apart on the same chromosome show very few recombinations
- C. Genes loosely linked on the same chromosome show moderate recombinations
- D. Tightly linked genes on the same chromosome show very few recombinations
Explanation: Linkage refers to the tendency of genes located close to each other on the same chromosome to be inherited together during meiosis.
Correct answer: Tightly linked genes on the same chromosome show very few recombinations- A. The discrete unit controlling a particular character is called a factor
- B. Out of one pair of factors, one is dominant, and the other is recessive
- C. Alleles do not show any blending and both the characters recover as such in the F2 generation
- D. Factors occur in pairs
Explanation: Option C is the correct choice because it describes a phenomenon explained by Mendel's law of independent assortment, not the law of…
Correct answer: Alleles do not show any blending and both the characters recover as such in the F2 generation- A. All color blind
- B. All normal visioned
- C. One-half color blind and one-half normal
- D. Three-fourths color blind and one-fourth normal
Explanation: Color blindness is a recessive, sex-linked trait carried on the X chromosome.
Correct answer: All color blind- A. It expresses its effect only in homozygous state
- B. It expresses its effect only in heterozygous condition
- C. It expresses its effect both in homozygous and heterozygous condition
- D. It never expresses its effect in any condition
Explanation: A gene is considered dominant if it expresses its effect in both homozygous (two copies of the dominant allele) and heterozygous (one…
Correct answer: It expresses its effect both in homozygous and heterozygous condition- A. Down's syndrome - 21st chromosome
- B. Sickle cell anaemia - X chromosome
- C. Haemophilia - Y chromosome
- D. Parkinson's disease - X and Y chromosome
Explanation: The correct answer is Option A: Down's syndrome is caused by the presence of an extra copy of chromosome 21, known as trisomy 21.
Correct answer: Down's syndrome - 21st chromosome- A. 9 : 3 : 4
- B. 12 : 3 : 1
- C. 9 : 3 : 3 : 1
- D. 9 : 7
Explanation: The correct answer is 9 : 7 (Option D). Complementary gene interaction occurs when two different genes work in tandem, with the presence…
Correct answer: 9 : 7- A. Genes are located on homologous chromosomes
- B. Genes are linked and located on the same chromosome
- C. Genes are located on non-homologous chromosomes
- D. All of these
Explanation: Independent assortment of genes occurs when genes are located on different chromosomes or far apart on the same chromosome, allowing them…
Correct answer: Genes are linked and located on the same chromosome- A. In humans, the Y chromosome is crucial for male sex determination
- B. The Y chromosome is integral to sex determination in both humans and Drosophila
- C. In Drosophila, the Y chromosome determines femaleness
- D. The Y chromosome contains genes for Klinefelter's syndrome in humans
Explanation: The question explores the different roles of the Y chromosome in sex determination across species.
Correct answer: In humans, the Y chromosome is crucial for male sex determination- A. Colour blind sons and 50% carrier daughters
- B. 50% colour blind sons and 50% carrier daughters
- C. Normal males and carrier daughters
- D. Colour blind sons and carrier daughters
Explanation: In X-linked recessive inheritance, males have one X chromosome and one Y chromosome.
Correct answer: Colour blind sons and carrier daughters- A. The Y-chromosome of males has the genes for distinguishing colours
- B. Genes responsible for certain traits, including colour blindness, are located on the X chromosome, which is part of the sex chromosomes
- C. The trait is dominant in males and recessive in females
- D. None of the above
Explanation: Color blindness is caused by a recessive gene located on the X chromosome.
Correct answer: Genes responsible for certain traits, including colour blindness, are located on the X chromosome, which is part of the sex chromosomes- A. X-chromosome of father
- B. Y-chromosome of father
- C. One X-chromosome of mother
- D. Both X-chromosomes of mother
Explanation: The gene for hemophilia is located on one of the X-chromosomes of the mother, making her a carrier.
Correct answer: One X-chromosome of mother- A. The principle of independent assortment is incorrect
- B. Mendel might not have studied all the combinations
- C. It is impossible
- D. Later studies may be incorrect
Explanation: The correct answer is that Mendel might not have studied all the combinations.
Correct answer: Mendel might not have studied all the combinations- A. IOIO
- B. IBIB
- C. IAIB
- D. IBIO
Explanation: The child has an O-group, indicating a genotype of IOIO, which means both parents must contribute an IO allele.
Correct answer: IBIO- A. Her mother and maternal grandfather were colour blind
- B. Her father and maternal grandfather were colour blind
- C. Her mother is colour blind and father has normal vision
- D. Parents have normal vision but grandparents were colour blind
Explanation: The correct option is B: Her father and maternal grandfather were colour blind.
Correct answer: Her father and maternal grandfather were colour blind- A. Recessive character carried by Y-chromosome
- B. Dominant character carried by Y-chromosome
- C. Dominant trait carried by X-chromosome
- D. Recessive trait carried by X-chromosome
Explanation: The correct option is d) Recessive trait carried by X-chromosome.Hemophilia is a genetic disorder that affects the blood's ability to clot…
Correct answer: Recessive trait carried by X-chromosome- A. The trait for albinism is dominant
- B. The albinos have a biochemical to destroy plastids derived from the green male
- C. Plastids are inherited from the female parent
- D. Green plastids of the male must have mutated
Explanation: This question is tough and is included in the QBank for the thorough preparation of Students.The correct answer is that plastids are…
Correct answer: Plastids are inherited from the female parent- A. 0%
- B. 25%
- C. 50%
- D. 100%
Explanation: In humans, sex determination is governed by the X and Y chromosomes. A female (XX) can only provide an X chromosome, while a male (XY) can…
Correct answer: 50%1139. The alleles are:
- A. A pair of genes governing a specific character
- B. Genes governing eye characters
- C. Multiple forms of genes
- D. Genes present on allosomes
Explanation: Multiple alleles .' Alleles are different versions of the same gene found at a particular locus on a chromosome.
Correct answer: Multiple forms of genes- A. Complete dominance and Co-dominance
- B. Incomplete dominance and Co-dominance
- C. Over dominance and Incomplete dominance
- D. Complete dominance only
Explanation: The ABO blood group system is a classic example of both complete dominance and co-dominance.
Correct answer: Complete dominance and Co-dominance