Chapter 5: Molecular Genetics — Online MCQ Test
ZOOLOGY · CLASS 12th · Tamil Nadu State Board
Practice Chapter 5: Molecular Genetics with a free chapter-wise online MCQ test.
This chapter covers: Focusing on DNA structure and function this chapter details replication transcription translation gene regulation Human Genome Project and DNA fingerprinting techniques..
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter 5: Molecular Genetics — Important Questions & Answers
Which sugar is present in the backbone of DNA?
- A. Ribose
- B. Deoxyribose
- C. Glucose
- D. Fructose
Answer: B. Deoxyribose
DNA contains deoxyribose sugar, which lacks one oxygen atom compared to ribose. This is a basic structural feature of DNA.
DNA contains deoxyribose sugar, which lacks one oxygen atom compared to ribose. This is a basic structural feature of DNA.
The process by which DNA makes an identical copy of itself is called ______.
- A. Transcription
- B. Translation
- C. Replication
- D. Mutation
Answer: C. Replication
Replication is the copying of DNA before cell division. It ensures genetic information is passed to daughter cells.
Replication is the copying of DNA before cell division. It ensures genetic information is passed to daughter cells.
If the template DNA strand has the sequence 3'-T A C-5', what is the complementary mRNA sequence?
- A. 5'-A U G-3'
- B. 5'-T A C-3'
- C. 5'-U A C-3'
- D. 5'-A T G-3'
Answer: A. 5'-A U G-3'
During transcription, RNA nucleotides pair with the DNA template strand using uracil in place of thymine. Thus, TAC on DNA gives AUG on mRNA.
During transcription, RNA nucleotides pair with the DNA template strand using uracil in place of thymine. Thus, TAC on DNA gives AUG on mRNA.
A student observes that a DNA sample from a crime scene matches the suspect at all tested VNTR loci. What is the most appropriate conclusion?
- A. The suspect is definitely guilty without any further evidence
- B. The DNA profile strongly suggests the suspect may be the source, but other evidence is also needed
- C. The DNA sample must be RNA contamination
- D. The test proves the suspect's blood group only
Answer: B. The DNA profile strongly suggests the suspect may be the source, but other evidence is also needed
A DNA fingerprint match provides strong evidence of identity, but it is not the sole basis for guilt in legal investigations. Additional evidence is needed.
A DNA fingerprint match provides strong evidence of identity, but it is not the sole basis for guilt in legal investigations. Additional evidence is needed.
During translation, the initiator tRNA first pairs with the start codon on mRNA. Which codon serves as the usual start codon?
- A. UAA
- B. AUG
- C. UGA
- D. UAG
Answer: B. AUG
AUG is the start codon in most organisms and codes for methionine. It signals the beginning of translation.
AUG is the start codon in most organisms and codes for methionine. It signals the beginning of translation.