Mendelian Genetics and Heredity - Advanced Concepts
Q. In a dihybrid cross, what is the expected phenotypic ratio in the F2 generation?
A.3:1
B.1:2:1
C.9:3:3:1
D.1:1:1:1
Solution
The expected phenotypic ratio in the F2 generation of a dihybrid cross is 9:3:3:1, representing the combinations of two traits.
Correct Answer: C — 9:3:3:1
Q. What is the expected genotypic ratio in the F2 generation of a monohybrid cross?
A.1:2:1
B.3:1
C.9:3:3:1
D.1:1
Solution
The expected genotypic ratio in the F2 generation of a monohybrid cross is 1:2:1, representing the homozygous dominant, heterozygous, and homozygous recessive genotypes.
Correct Answer: A — 1:2:1
Q. What is the expected phenotypic ratio in the F2 generation of a monohybrid cross?
A.3:1
B.1:2:1
C.9:3:3:1
D.1:1
Solution
In a monohybrid cross, the expected phenotypic ratio in the F2 generation is 3:1, where three offspring display the dominant trait and one displays the recessive trait.
Correct Answer: A — 3:1
Q. What is the primary function of ribosomes in cells?
A.DNA replication
B.RNA synthesis
C.Protein synthesis
D.Lipid synthesis
Solution
Ribosomes are the cellular structures responsible for protein synthesis, translating messenger RNA (mRNA) into polypeptide chains.
Correct Answer: C — Protein synthesis
Q. What is the role of RNA polymerase in gene expression?
A.To replicate DNA
B.To synthesize RNA from a DNA template
C.To splice RNA
D.To translate RNA into protein
Solution
RNA polymerase synthesizes RNA from a DNA template during the process of transcription in gene expression.
Correct Answer: B — To synthesize RNA from a DNA template
Q. Which of the following best describes a test cross?
A.Crossing two homozygous individuals
B.Crossing a homozygous individual with a heterozygous individual
C.Crossing an individual with an unknown genotype with a homozygous recessive
D.Crossing two heterozygous individuals
Solution
A test cross involves crossing an individual with an unknown genotype with a homozygous recessive individual to determine the genotype of the former.
Correct Answer: C — Crossing an individual with an unknown genotype with a homozygous recessive
Q. Which of the following describes a phenotype?
A.The genetic makeup of an organism
B.The observable characteristics of an organism
C.The location of a gene on a chromosome
D.The sequence of nucleotides in DNA
Solution
A phenotype refers to the observable characteristics or traits of an organism, which result from the interaction of its genotype with the environment.
Correct Answer: B — The observable characteristics of an organism
Q. Which of the following is NOT a characteristic of Mendelian inheritance?
A.Segregation of alleles
B.Independent assortment
C.Incomplete dominance
D.Dominance
Solution
Incomplete dominance is not a characteristic of Mendelian inheritance; it describes a situation where the phenotype is intermediate between the two parental traits.
Correct Answer: C — Incomplete dominance
Q. Which of the following techniques is used to amplify DNA?
A.Gel electrophoresis
B.Polymerase chain reaction (PCR)
C.Southern blotting
D.Sanger sequencing
Solution
Polymerase chain reaction (PCR) is a technique used to amplify specific DNA sequences, making millions of copies of a particular segment.
Correct Answer: B — Polymerase chain reaction (PCR)
