Blog Log in Get Started Free

Chemistry MCQs for NEET — Practice Questions with Answers

Practice free Chemistry NEET multiple-choice questions online with instant answers and detailed explanations. No login required.

All Physics Chemistry Botany Zoology

Chapter Language Difficulty Show only questions I answered incorrectly Register free to filter questions

● ● ● ● ●

Which of the following pentose sugars is found in RNA, and how does it differ structurally from the sugar in DNA?

A. deoxyribose, lacking a hydroxyl group at the 2' carbon. B. Ribose, having a hydroxyl group at the 2' carbon. C. Glucose, a six-carbon sugar. D. Fructose, a ketohexose.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The context mentions: 'DNA contains a five carbon sugar molecule called 2-deoxyribose whereas RNA contains ribose.' And 'Further, 2'-OH group present at every nucleotide in RNA is a reactive group...' indicating ribose has this group, while deoxyribose lacks it.

● ● ● ● ●

Why do viruses with RNA genomes often mutate and evolve faster than those with DNA genomes?

A. Because RNA is chemically less stable and mutates at a faster rate. B. Because RNA genomes are always longer than DNA genomes. C. Because RNA replication machinery is more error-prone than DNA replication machinery. D. Because RNA genomes are double-stranded, allowing for more recombination.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The text explains: 'In fact, RNA being unstable, mutate at a faster rate. Consequently, viruses having RNA genome and having shorter life span mutate and evolve faster.'

● ● ● ● ●

Which of the following is NOT a type of RNA mentioned in the context to be involved in protein synthesis?

A. mRNA (messenger RNA) B. rRNA (ribosomal RNA) C. tRNA (transfer RNA) D. gRNA (guide RNA)

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The context explicitly lists: 'RNA molecules are of three types and they perform different functions. They are named as messenger RNA (m-RNA), ribosomal RNA (r-RNA) and transfer RNA (t-RNA).'

● ● ● ● ●

Both DNA and RNA possess all of the following nitrogenous bases EXCEPT:

A. Adenine B. Guanine C. Cytosine D. Thymine

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The text states: 'Both DNA and RNA contain adenine, guanine and cytosine. The fourth base is thymine in DNA and uracil in RNA.' Therefore, thymine is present only in DNA, not both.

● ● ● ● ●

Which feature of DNA contributes to its ability to serve as a better genetic material compared to RNA?

A. Its ability to act as a catalyst (ribozyme). B. Its single-stranded nature allowing for rapid change. C. Its chemical inertness and structural stability. D. Its direct involvement in protein synthesis.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The text states: 'Therefore, DNA chemically is less reactive and structurally more stable when compared to RNA. Therefore, among the two nucleic acids, the DNA is a better genetic material.'

● ● ● ● ●

The protein synthesizing machinery has evolved around which nucleic acid?

A. DNA B. RNA C. Both DNA and RNA equally D. Neither DNA nor RNA, but rather proteins.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The NCERT text mentions: 'The protein synthesising machinery has evolved around RNA.' And in the summary, 'Translation is a process that has evolved around RNA, indicating that life began around RNA.'

● ● ● ● ●

What is the primary structural difference between the secondary structures of DNA and RNA?

A. DNA forms a single-stranded helix, while RNA forms a double helix. B. DNA forms a double-stranded helix, while RNA forms a single-stranded helix which sometimes folds back on itself. C. Both DNA and RNA form triple helices, but with different base pairings. D. DNA is always linear, while RNA is always circular.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The text states: 'James Watson and Francis Crick gave a double strand helix structure for DNA... In secondary structure of RNA single stranded helics is present which sometimes foldsback on itself.'

● ● ● ● ●

Which of the following criteria for a genetic material is better fulfilled by DNA than by RNA?

A. Ability to generate its replica. B. Ability to undergo slow changes (mutation). C. Structural and chemical stability. D. Ability to express itself in the form of 'Mendelian Characters'.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The text lists criteria for genetic material and states: 'The genetic material should be stable enough not to change with different stages of life cycle... Therefore, DNA chemically is less reactive and structurally more stable when compared to RNA. Therefore, among the two nucleic acids, the DNA is a better genetic material.'

● ● ● ● ●

In the context of genetic material and evolution, what is the implication of RNA's higher mutation rate?

A. It makes RNA a less effective genetic material for all organisms. B. It allows organisms with RNA genomes to evolve faster. C. It leads to increased genomic stability in RNA viruses. D. It prevents RNA from being used as genetic material.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The context highlights: 'RNA being unstable, mutate at a faster rate. Consequently, viruses having RNA genome and having shorter life span mutate and evolve faster.'

● ● ● ● ●

A nucleotide is composed of which three components?

A. nitrogenous base, a hexose sugar, and a phosphate group. B. nitrogenous base, a pentose sugar, and a phosphate group. C. An amino acid, a pentose sugar, and a fatty acid. D. nitrogenous base, an amino sugar, and a lipid.

You've reached today's free limit of 20 questions. Log in to keep practising for free.

Explanation

The NCERT text explicitly states: 'A nucleotide has three components â€“ a nitrogenous base, a pentose sugar (ribose in case of RNA, and deoxyribose for DNA), and a phosphate group.'

Ready to ace NEET?

Free access · No credit card required

Browse All Questions Create Free Account

Frequently Asked Questions

Yes. You can attempt every Chemistry question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.

No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.

The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.