Match List-I (Linkage/Recombination Data in Drosophila Cross A and Cross B) with List-II (Value/Concept):
List-I
List-II
A. Recombination percentage between yellow and white genes
I. 1.3 per cent
B. Recombination percentage between white and miniature wing genes
II. 37.2 per cent
C. Tightly linked genes
III. Show very low recombination
D. Linkage
IV. Physical association of genes on a chromosome
Choose the correct answer from the options given below:
Yellow and white genes showed 1.3% recombination (tight linkage). White and miniature wing genes showed 37.2% recombination (looser linkage).
Question 302 of 519
📘 CLASS XII
Match List-I (Basic Ratios) with List-II (Monohybrid/Dihybrid/Test Cross):
List-I
List-II
A. F2 Phenotypic Ratio (Monohybrid Cross)
I. 3:1
B. F2 Genotypic Ratio (Monohybrid Cross)
II. 1:2:1
C. F2 Phenotypic Ratio (Dihybrid Cross)
III. 9:3:3:1
D. Test Cross (Tt x tt)
IV. 1:1
Choose the correct answer from the options given below:
The F2 phenotypic ratio for a monohybrid cross is 3:1. The F2 genotypic ratio for a monohybrid cross is 1:2:1. The F2 phenotypic ratio for a dihybrid cross is 9:3:3:1. A test cross (Tt x tt) produces a 1:1 phenotypic ratio (e.g., violet:white).
Question 303 of 519
📘 CLASS XII
Match List-I (Non-Mendelian Phenomena) with List-II (Trait/Mechanism):
List-I
List-II
A. Polygenic Inheritance
I. Traits generally controlled by three or more genes
B. Pleiotropy
II. Single gene exhibits multiple phenotypic expressions
C. Human Skin Colour
III. Phenotype influenced by multiple genes and environment
D. Phenylketonuria
IV. Classic example of pleiotropic disease in humans
Choose the correct answer from the options given below:
Polygenic traits are controlled by three or more genes. Pleiotropy is where a single gene produces multiple effects. Human skin colour is a classic example of polygenic inheritance influenced by environment. Phenylketonuria is a disease caused by a pleiotropic gene mutation.
Question 304 of 519
📘 CLASS XII
Match List-I (ABO Blood Group Genotype) with List-II (Phenotype):
List-I
List-II
A. IA IA
I. Blood Group A
B. IA IB
II. Blood Group AB
C. IB i
III. Blood Group B
D. i i
IV. Blood Group O
Choose the correct answer from the options given below:
The phenotypes correspond directly to the genotypes provided in the table detailing the genetic basis of blood groups.
Question 305 of 519
📘 CLASS XII
Match List-I (Sex Chromosome Karyotype) with List-II (Associated Human Syndrome/Condition):
List-I
List-II
A. 47, XXY
I. Klinefelter’s Syndrome
B. 45, X0
II. Turner’s Syndrome
C. Trisomy of Chromosome 21
III. Down’s Syndrome
D. Aneuploidy
IV. Gain or loss of chromosomes due to failure of segregation
Choose the correct answer from the options given below:
Klinefelter’s Syndrome has the karyotype 47, XXY. Turner’s Syndrome is 45, X0. Down’s Syndrome is caused by Trisomy 21. Aneuploidy is the gain or loss of a chromosome(s).
Question 306 of 519
📘 CLASS XII
Match List-I (Sex-Linked Trait Feature) with List-II (Disorder):
List-I
List-II
A. Non-stop bleeding from a simple cut
I. Haemophilia
B. Failure to discriminate between red and green colour
II. Colour Blindness
C. X-linked recessive trait
III. Transmission from carrier female to male progeny
D. Queen Victoria
IV. Famous carrier of Haemophilia disease
Choose the correct answer from the options given below:
Haemophilia is a sex-linked recessive disease causing non-stop bleeding. Colour blindness is due to failure to discriminate red/green colour. X-linked recessive traits show transmission from carrier female to male progeny. Queen Victoria was a known carrier of Haemophilia.
Question 307 of 519
📘 CLASS XII
Match List-I (Mendel’s Factors/Laws) with List-II (Core Concept):
List-I
List-II
A. Factors (Genes)
I. Contain information required to express a particular trait
B. Law of Independent Assortment
II. Segregation of one pair of characters is independent of the other pair
C. Alleles of a pair
III. Separate or segregate during gamete formation (Meiosis)
D. Dominant Allele
IV. The unmodified allele that produces a functional enzyme
Choose the correct answer from the options given below:
Factors (genes) contain the information for a trait. The Law of Independent Assortment deals with the independent segregation of two pairs of characters. Alleles of a pair segregate during gamete formation. The dominant allele is often the unmodified allele producing a functional enzyme.
Question 308 of 519
📘 CLASS XII
Match List-I (Trait/Phenotype) with List-II (Gene/Allele Relationship):
List-I
List-II
A. Starch grain size in pea (Bb)
I. Incomplete dominance
B. Seed shape in pea (Bb)
II. Complete dominance
C. Flower color in Snapdragon (Rr)
III. Intermediate phenotype (Pink)
D. ABO blood grouping
IV. Co-dominance and Multiple alleles
Choose the correct answer from the options given below:
Starch grain size in Bb is intermediate, showing incomplete dominance. Seed shape in Bb is round, showing complete dominance of R. Snapdragon Rr results in pink, an intermediate phenotype. ABO blood grouping involves three alleles (IA, IB, i) and shows co-dominance (IA IB).
Question 309 of 519
📘 CLASS XII
Match List-I (Inheritance Studies) with List-II (Time Period/Context):
List-I
List-II
A. Mendel’s Hybridisation Experiments
I. 1856-1863 (Seven years)
B. Publication of Mendel’s work
II. 1865
C. Rediscovery of Mendel’s work (de Vries, Correns, von Tschermak)
III. 1900
D. Discovery of the X body (Henking)
IV. 1891
Choose the correct answer from the options given below:
Mendel conducted experiments for seven years (1856-1863). He published his work in 1865. The work was independently rediscovered by three scientists in 1900. Henking traced the X body in 1891.
Question 310 of 519
📘 CLASS XII
Match List-I (Genetic Terminology) with List-II (Mathematical Context):
List-I
List-II
A. Punnett Square
I. Graphical representation of offspring probability
B. Monohybrid F2 Genotype ratio (1:2:1)
II. Condensable to binomial expression (ax + by)2
C. Gamete formation (Tt plant)
III. 50 per cent chance of containing either allele
D. Dihybrid Cross F2
IV. Production of 16 possible zygote combinations
Choose the correct answer from the options given below:
Punnett Square is a graphical representation to calculate probability. The 1:2:1 ratio is mathematically condensable to the binomial expression (ax + by)2. Gamete formation from Tt has a 50% chance for T or t. Dihybrid crosses involve 16 combinations in F2 using the Punnett Square.
