Mendelian Genetics and Heredity - Competitive Exam Level
Q. What is the expected phenotypic ratio of a test cross involving a heterozygous individual?
-
A.
1:1
-
B.
3:1
-
C.
9:3:3:1
-
D.
1:2:1
Solution
The expected phenotypic ratio of a test cross involving a heterozygous individual is 1:1, as it is crossed with a homozygous recessive individual.
Correct Answer: A — 1:1
Q. What is the function of a promoter in gene expression?
-
A.
To enhance transcription
-
B.
To initiate transcription
-
C.
To terminate transcription
-
D.
To bind ribosomes
Solution
A promoter is a DNA sequence that initiates transcription by providing a binding site for RNA polymerase.
Correct Answer: B — To initiate transcription
Q. Which of the following is a characteristic of autosomal dominant inheritance?
-
A.
Trait skips generations
-
B.
Both males and females are equally affected
-
C.
Affected individuals are always homozygous
-
D.
Only males can transmit the trait
Solution
In autosomal dominant inheritance, both males and females are equally affected, and the trait does not skip generations.
Correct Answer: B — Both males and females are equally affected
Q. Which of the following represents a homozygous recessive genotype?
Solution
A homozygous recessive genotype is represented by 'aa', where both alleles are recessive.
Correct Answer: C — aa
Q. Which type of mutation involves the substitution of one nucleotide for another?
-
A.
Insertion
-
B.
Deletion
-
C.
Point mutation
-
D.
Frameshift mutation
Solution
A point mutation involves the substitution of one nucleotide for another, potentially altering the amino acid sequence.
Correct Answer: C — Point mutation
Showing 1 to 5 of 5 (1 Pages)
