Genetics – Some Basic Fundamentals assertion reason questions for Class 10 ICSE
Question 1: Assertion (A): Genes are the units of heredity.
Reason (R): Alleles are different forms of the same gene.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 2: Assertion (A): DNA is a double-stranded helix.
Reason (R): Adenine pairs with guanine in DNA.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 3: Assertion (A): Mendel’s law of segregation states that during gamete formation, the alleles segregate independently of each other.
Reason (R): Meiosis is the process by which gametes are formed.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 4: Assertion (A): Homozygous individuals have two identical alleles for a particular gene.
Reason (R): Heterozygous individuals have different alleles for a specific gene.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 5: Assertion (A): Mutation is the source of all genetic variations.
Reason (R): Mutations always result in harmful effects.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Question 6: Assertion (A): Incomplete dominance is when the phenotype of the heterozygote is intermediate between the phenotypes of the two homozygotes.
Reason (R): Co-dominance is when both alleles are fully expressed in the heterozygote.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 7: Assertion (A): Chromosomes are made of DNA and proteins.
Reason (R): Genes are located on chromosomes.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 8: Assertion (A): The Punnett square is a tool used to predict the outcome of a particular cross or breeding experiment.
Reason (R): Dominant alleles are always expressed over recessive alleles.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Question 9: Assertion (A): Sex-linked traits are more commonly observed in males than in females.
Reason (R): Sex-linked traits are carried on the Y chromosome.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Question 10: Assertion (A): Evolution occurs due to changes in the genetic makeup of a population over time.
Reason (R): Natural selection is the only mechanism for evolutionary change.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Question 11: Assertion (A): A phenotype is the physical appearance of an organism.
Reason (R): Genotype refers to the genetic makeup of an organism.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 12: Assertion (A): The law of independent assortment states that genes for different traits segregate independently during the formation of gametes.
Reason (R): Homologous chromosomes pair up and exchange genetic material during meiosis.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (b) Both A and R are False
Question 13: Assertion (A): Genetic recombination during meiosis contributes to genetic diversity.
Reason (R): Crossing over occurs between non-homologous chromosomes.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (d) A is False and R is True.
Question 14: Assertion (A): A carrier is an individual who has a recessive allele for a genetic trait but does not express the trait.
Reason (R): Recessive traits skip generations in a pedigree.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 15: Assertion (A): Environmental factors can influence gene expression.
Reason (R): Epigenetics refers to changes in gene expression that do not involve changes to the underlying DNA sequence.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 16: Assertion (A): In a dihybrid cross, the inheritance of two different traits is studied simultaneously. Reason (R): The law of segregation is applied to dihybrid crosses.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 17: Assertion (A): A gene can have multiple alleles.
Reason (R): Multiple alleles always result in multiple phenotypes for a specific trait.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 18: Assertion (A): Punnett squares can predict the probability of offspring having specific genotypes. Reason (R): Phenotypes are directly determined by Punnett squares.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Question 19: Assertion (A): DNA replication is a semi-conservative process.
Reason (R): DNA polymerase is the enzyme responsible for proofreading and repairing errors in DNA replication.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 20: Assertion (A): Down syndrome is caused by the presence of an extra copy of chromosome
Reason (R): Down syndrome is an inherited disorder.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 21: Assertion (A): Hemophilia is a sex-linked disorder.
Reason (R): Hemophilia is more common in females.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 22: Assertion (A): Sickle cell anemia is caused by a mutation in the hemoglobin gene.
Reason (R): Sickle cell anemia is an autosomal recessive disorder.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 23: Assertion (A): A genotype of ‘TT’ represents homozygous dominant alleles.
Reason (R): Homozygous recessive individuals express the dominant phenotype.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 24: Assertion (A): Genetic engineering involves altering the DNA of an organism.
Reason (R): Selective breeding and hybridization are forms of genetic engineering.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 25: Assertion (A): A karyotype is a visual arrangement of an individual’s chromosomes.
Reason (R): Karyotyping can reveal chromosomal abnormalities.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 26: Assertion (A): Test crosses are used to determine the genotype of an individual displaying a dominant trait.
Reason (R): Test crosses involve crossing an individual with a known recessive genotype.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 27: Assertion (A): In gene therapy, functional genes are introduced into cells to correct genetic disorders.
Reason (R): Gene therapy is always successful in treating genetic disorders.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 28: Assertion (A): Genetic drift can lead to changes in the frequency of alleles in a population.
Reason (R): Genetic drift has a more significant effect in larger populations.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 29: Assertion (A): The Hardy-Weinberg equilibrium describes a theoretical state in which allele frequencies in a population remain constant.
Reason (R): Evolution is the only factor that can disturb the Hardy-Weinberg equilibrium.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 30: Assertion (A): Genetic linkage refers to the tendency of certain genes to be inherited together. Reason (R): Genetic linkage violates Mendel’s law of independent assortment.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Question 31: Assertion (A): Genetic recombination between linked genes can occur through crossing over.
Reason (R): Crossing over involves the exchange of genetic material between non-homologous chromosomes.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (d) A is False and R is True.
Question 32: Assertion (A): A monohybrid cross involves the study of one trait inheritance.
Reason (R): The ratio of genotypes in a monohybrid cross is 9:3:3:1.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 33: Assertion (A): Genetically modified organisms (GMOs) are produced by altering their DNA through biotechnology.
Reason (R): All genetically modified organisms are suitable for human consumption without any potential risks. (a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 34: Assertion (A): RNA is single-stranded and involved in protein synthesis.
Reason (R): Messenger RNA (mRNA) carries the genetic code from DNA to the ribosomes.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (a) Both A and R are True
Question 35: Assertion (A): Evolution occurs due to natural selection and other mechanisms such as genetic drift, gene flow, and mutations.
Reason (R): Natural selection always leads to the creation of new species.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True.
Answer:- (c) A is True and R is False
Also See: Structure of Chromosomes, Cell Cycle and Cell Division Class 10 Assertion Reason Questions