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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Read the Inheritance notesFree MDCAT chapter notes with key terms1,238 questions · page 50 of 62
- A. Polymorphic gene
- B. Homomorphic gene
- C. Isomorphic gene
- D. Amorphic gene
Explanation: Having more than two morphological (Phenotypic) manifestations or having more than two alleles.
Correct answer: Polymorphic gene982. If the alterations involve only one or a few base pairs in the coding sequence they are called:
- A. Chromosomal mutations
- B. Mega changes
- C. Chromosomal aberrations
- D. Point mutation
Explanation: As it occurs at nucleotide level or molecular level and is called point mutation or molecular mutation of gene mutation.
Correct answer: Point mutation- A. Mutagenic radiations
- B. Spontaneous pairing errors
- C. Chemical mutagens
- D. Non-disjunction
Explanation: Such chemicals which cause point mutations are called chemical mutagens.
Correct answer: Chemical mutagens- A. Point mutations
- B. Chromosomal aberrations
- C. Chromosomal mutations
- D. Non-disjunction
Explanation: These genetic disorders are consequence of a change in the nucleotide sequence of DNA which results in a change in amino acid sequence of…
Correct answer: Point mutations- A. Glutamic acid into serine
- B. Serine into glutamic acid
- C. Glutamic acid into valine
- D. Valine into glutamic acid
Explanation: Glutamic acid is replaced by valine as thymine have been replaced by adenine in gene regulating the synthesis of hemoglobin.
Correct answer: Glutamic acid into valine- A. 23 autosome, one pair of sex chromosomes
- B. 22 autosome, one pair of sex chromosomes
- C. 23 pairs of autosome, one pair of sex chromosomes
- D. 22 pairs of autosome, one pair of sex chromosomes
Explanation: T.H. Morgan classified the chromosomes into two functional categories i.e. autosomes and sex chromosomes.
Correct answer: 22 pairs of autosome, one pair of sex chromosomes- A. X chromosome
- B. Two X chromosomes
- C. Y chromosome
- D. XY chromosomes
Explanation: Female have XX chromosomes whereas male have XY chromosome.
Correct answer: Two X chromosomes- A. One non-homologous pairs of chromosomes
- B. 23 non-homologous pairs of chromosomes
- C. 22 homologous pairs of chromosome
- D. 23 homologous pairs of chromosome
Explanation: Sex chromosomes are also homologous in female (XX) whereas autosomes are homologous in both male and females.
Correct answer: One non-homologous pairs of chromosomes- A. tfm
- B. SRY
- C. SDRY
- D. TSDRY
Explanation: Sex determining region of the Y-chromosome.
Correct answer: SRY- A. Presence of Y chromosome
- B. Presence of SRY gene on Y chromosome
- C. X-Y balance
- D. Autosome and X chromosome balance
Explanation: Presence of SRY on the short arm of Y-chromosome is inevitable for triggering male development in the embryo.
Correct answer: Presence of SRY gene on Y chromosome991. In humans:
- A. Same type of gametes are produced
- B. Same type of sperms are produced
- C. Same type of eggs are produced
- D. Dfferent type of eggs are produced
Explanation: A small pairs of chromosomes are homologous in female. However, sperms are of two types.
Correct answer: Same type of eggs are produced- A. 1:2:1
- B. 2:1
- C. 1:1
- D. 3:1
Explanation: According to probability rule, the chances for two types of sperms in fertilizing the single type of egg are fifty fifty.
Correct answer: 1:1- A. Female
- B. Male
- C. Abnormal male
- D. Abnormal female
Explanation: All the eggs of human female carry X-chromosome. However male produces two types of sperms; half having X-chromosomes and half having…
Correct answer: Female- A. Evolution
- B. Mutation
- C. Reshuffling
- D. Crossing over
Explanation: Mutation is a source of formation of multiple alleles.
Correct answer: Mutation- A. Allelomorphs
- B. Fixed alleles
- C. Multiple alleles
- D. Pseudo alleles
Explanation: If a gene have more than two alternate forms or allelomorphs it is called a multiple alleles e.g. ABO blood type.
Correct answer: Multiple alleles- A. Antibodies against A
- B. Antibodies against O
- C. Antibodies against B
- D. Antibodies against A and B
Explanation: Antibodies are formed against that antigen which is absent in that body.
Correct answer: Antibodies against B- A. No antibodies
- B. Antibodies against B
- C. Antibodies against A
- D. Antibodies against A and B both
Explanation: A person lacking both antigen A and B will produce antibodies against both antigens as both antigens are foreign to him or her.
Correct answer: Antibodies against A and B both998. In phenylketonuria:
- A. Phenylalanine hydroxylase is not formed
- B. Phenylalanine hydroxylase is not degraded
- C. Phenylalanine is not formed
- D. Adenosine deaminase is not formed
Explanation: Phenylalanine hydroxylase enzyme is required to degrade phenylalanine. As a result phenylalanine accumulates in the cells leading to…
Correct answer: Phenylalanine hydroxylase is not formed- A. During embryonic development
- B. In childhood
- C. In infancy
- D. During puberty
Explanation: Phenylalanine accumulates during infancy in post embryonic development as during embryonic phase phenylalanine is metabolized by mother…
Correct answer: In infancy- A. Darwin
- B. Nilsson-Ehle
- C. Mendel
- D. Correns
Explanation: Nilsson-Ehle studied the genetics of wheat grain color. When he crossed a true breeding dark red grain plant with true breeding white…
Correct answer: Nilsson-Ehle