INI-CET 2012

Q: In humans, the genetic code is represented by a code of three nucleotides. If one amino acid is coded by more than one triplet, then this is known as?

Degeneracy. ### Explanation **1. Why "Degeneracy" is the Correct Answer:** The genetic code consists of 64 possible codons (triplets) that encode for only 20 standard amino acids. Because there are more codons than amino acids, most amino acids are specified by multiple codons. This phenomenon is termed **Degeneracy** (or Redundancy). * **Mechanism:** Degeneracy primarily occurs at the **third position** of the codon (the 3' end), often explained by the **Wobble Hypothesis**. For example, Leucine is coded by six different codons (UUA, UUG, CUU, CUC, CUA, CUG). This provides a protective mechanism against mutations, as a change in the third nucleotide may still result in the same amino acid (Silent Mutation). **2. Why Other Options are Incorrect:** * **Ambiguity:** This would mean one codon codes for multiple different amino acids. The genetic code is **non-ambiguous**; each specific codon always codes for only one specific amino acid. * **Frame-shift Mutation:** This occurs when the addition or deletion of nucleotides (not in multiples of three) shifts the reading frame, altering all subsequent amino acids. It is a type of mutation, not a property of the code itself. * **Mutation:** This is a general term for any permanent change in the DNA sequence. While degeneracy helps mitigate the effects of mutations, it is not a synonym for the process. **3. High-Yield Clinical Pearls for NEET-PG:** * **Universal Code:** The genetic code is nearly universal across all species. **Exception:** Human mitochondrial DNA (e.g., UGA codes for Tryptophan instead of a Stop codon). * **Non-overlapping & Comma-less:** The code is read sequentially from a fixed starting point without skipping any nucleotides. * **Initiation Codon:** **AUG** (Methionine). In prokaryotes, it codes for N-formylmethionine. * **Stop Codons (Nonsense Codons):** UAA (Ochre), UAG (Amber), UGA (Opal). These do not code for any amino acid. [Practice more INI-CET 2012 questions on OnCourse]

Q: In an act of tribadism, the active partner is known as: (AIIMS 12; COMEDK 14)

Butch. ***Butch*** - While this answer reflects the terminology used in the original examination, it's important to note that **"butch"** is primarily a **sociocultural identity term** describing masculine gender expression in lesbian relationships, rather than standard forensic medicine terminology. - In classical forensic medicine literature, the active partner in tribadism is more accurately termed a **"tribade"** (from Greek "tribein" = to rub). - Tribadism refers to a form of **female same-sex sexual activity** where the active partner achieves sexual gratification by **rubbing or pressing the vulva** against another woman's body, particularly the thigh, pubic region, or vulva. - This question reflects **historical exam terminology** rather than current forensic medicine standards. *Bugger* - This is an archaic/derogatory term historically used for a person who performs **anal intercourse** (buggery/sodomy). - The term is associated with **male same-sex activity** or unnatural sexual offenses under older legal frameworks. - It is **not related to tribadism**, which involves female same-sex activity without penetration. *Femme* - This is a sociocultural term describing the more **feminine-presenting partner** in some lesbian relationships. - It refers to **gender expression/identity**, not a forensic medicine classification of sexual acts. - This is **not standard medicolegal terminology** for describing roles in tribadism. *Catamite* - A catamite refers to a **young boy kept for homosexual purposes**, historically associated with pederasty in ancient civilizations. - This term is related to **male same-sex activity** and is entirely **irrelevant to tribadism**, which is a form of female same-sex sexual activity. - This is an archaic term rarely used in modern forensic medicine. [Practice more INI-CET 2012 questions on OnCourse]

Q: Which of the following is the aetiological agent most often associated with Epiglottitis in children -

Haemophilus influenzae type b. ***Haemophilus influenzae type b*** - Historically, **_Haemophilus influenzae_ type b (Hib)** was the most common cause of **epiglottitis** in children. - The introduction of the **Hib vaccine** has significantly reduced its incidence, but it remains a crucial consideration. *Neisseria sp* - **_Neisseria_ species** are typically associated with infections like **meningitis** and **gonorrhea**, not primary causes of epiglottitis. - While **_Neisseria meningitidis_** can cause invasive disease, it's not a common pathogen for epiglottitis. *Moraxella catarrhalis* - **_Moraxella catarrhalis_** is a common cause of **otitis media**, **sinusitis**, and **bronchitis**, especially in children. - It is not a principal cause of acute epiglottitis. *Streptococcus pneumoniae* - **_Streptococcus pneumoniae_** is a major cause of **pneumonia**, **otitis media**, **meningitis**, and **sepsis**. - While it can cause respiratory infections, it is not the most frequent pathogen associated with epiglottitis compared to Hib pre-vaccine era. [Practice more INI-CET 2012 questions on OnCourse]

Q: A patient on amphotericin B develops hypokalemia with a potassium level of 2.3 mEq/L. What is the appropriate K+ supplementation required for this patient?

80 mEq over 24 hours. ***80 mEq over 24 hours***- For a potassium level of 2.3 mEq/L (moderate to severe hypokalemia), **80 mEq over 24 hours** represents appropriate aggressive replacement while maintaining safety.- This dose accounts for both the **existing deficit** and **ongoing renal potassium wasting** caused by amphotericin B, which impairs renal tubular function.- Standard guidelines recommend **60-80 mEq daily** for moderate to severe hypokalemia, divided into multiple doses with continuous cardiac monitoring.- Higher doses risk **rebound hyperkalemia** and cardiac complications [1]; replacement should be titrated based on serial potassium measurements.*40 mEq over 24 hours*- This dosage is insufficient for correcting a potassium level of 2.3 mEq/L, particularly with **ongoing drug-induced renal losses**.- It may be appropriate for mild hypokalemia (3.0-3.5 mEq/L) or maintenance therapy, but not for this clinical scenario.*60 mEq over 24 hours*- While this represents a reasonable starting dose for moderate hypokalemia, it may be **insufficient** given the severity (K+ 2.3 mEq/L) and ongoing losses from amphotericin B.- This dose might require escalation after reassessment of potassium levels.*100-120 mEq over 24 hours*- This dose **exceeds standard safe replacement protocols** and risks causing rebound hyperkalemia and cardiac arrhythmias [1].- Maximum safe infusion rates are typically **10-20 mEq/hour** (up to 40 mEq/hour only in critical situations with intensive monitoring).- Such aggressive replacement is not recommended in standard clinical practice for this scenario. [Practice more INI-CET 2012 questions on OnCourse]

6 Previous Year Questions with Answers & Explanations

Questions

Subjects

All (6)Biochemistry (2)Forensic Medicine (1)Microbiology (1)Pharmacology (1)Physiology (1)

Biochemistry

2 questions

Q1Easy

Same amino acid is coded by multiple codons due to:

Q2Easy

In humans, the genetic code is represented by a code of three nucleotides. If one amino acid is coded by more than one triplet, then this is known as?

INI-CET 2012 - Biochemistry INI-CET Practice Questions and MCQs

Question 1: Same amino acid is coded by multiple codons due to:

A. Degeneracy (Correct Answer)
B. Frame-shift mutation
C. Transcription
D. Mutation

Explanation: ### Explanation **Correct Option: A. Degeneracy** The genetic code consists of 64 codons, but only 20 standard amino acids. **Degeneracy** (or redundancy) refers to the phenomenon where a single amino acid is specified by two or more different codons. This occurs because the third position of the codon (the **Wobble position**) is often less specific, allowing one tRNA to recognize multiple codons. For example, Leucine is coded by six different codons. This redundancy acts as a protective mechanism against minor mutations. **Why Incorrect Options are Wrong:** * **B. Frame-shift mutation:** This is a genetic mutation caused by the insertion or deletion of nucleotides in a number not divisible by three. This shifts the reading frame, usually resulting in a completely different or non-functional protein, rather than explaining the coding mechanism. * **C. Transcription:** This is the biological process of copying a segment of DNA into RNA by the enzyme RNA polymerase. It is a step in gene expression, not a property of the genetic code itself. * **D. Mutation:** This is a general term for any change in the DNA sequence. While mutations can lead to changes in amino acids (missense) or premature stops (nonsense), they do not define the multi-codon relationship for a single amino acid. **High-Yield Clinical Pearls for NEET-PG:** * **Universal Code:** The genetic code is the same in almost all organisms, with minor exceptions (e.g., **Mitochondrial DNA**, where UGA codes for Tryptophan instead of a Stop codon). * **Non-overlapping & Commaless:** The code is read sequentially, three bases at a time, without skipping any nucleotides. * **Wobble Hypothesis:** Proposed by Francis Crick; it explains why we don't need 61 different tRNAs for 61 codons. The 5' base of the tRNA anticodon can form non-standard base pairs with the 3' base of the mRNA codon. * **Unambiguous:** While one amino acid can have many codons (Degeneracy), **one codon always codes for only one specific amino acid.**

Question 2: In humans, the genetic code is represented by a code of three nucleotides. If one amino acid is coded by more than one triplet, then this is known as?

A. Degeneracy (Correct Answer)
B. Frame-shift mutation
C. Ambiguity
D. Mutation

Explanation: ### Explanation **1. Why "Degeneracy" is the Correct Answer:** The genetic code consists of 64 possible codons (triplets) that encode for only 20 standard amino acids. Because there are more codons than amino acids, most amino acids are specified by multiple codons. This phenomenon is termed **Degeneracy** (or Redundancy). * **Mechanism:** Degeneracy primarily occurs at the **third position** of the codon (the 3' end), often explained by the **Wobble Hypothesis**. For example, Leucine is coded by six different codons (UUA, UUG, CUU, CUC, CUA, CUG). This provides a protective mechanism against mutations, as a change in the third nucleotide may still result in the same amino acid (Silent Mutation). **2. Why Other Options are Incorrect:** * **Ambiguity:** This would mean one codon codes for multiple different amino acids. The genetic code is **non-ambiguous**; each specific codon always codes for only one specific amino acid. * **Frame-shift Mutation:** This occurs when the addition or deletion of nucleotides (not in multiples of three) shifts the reading frame, altering all subsequent amino acids. It is a type of mutation, not a property of the code itself. * **Mutation:** This is a general term for any permanent change in the DNA sequence. While degeneracy helps mitigate the effects of mutations, it is not a synonym for the process. **3. High-Yield Clinical Pearls for NEET-PG:** * **Universal Code:** The genetic code is nearly universal across all species. **Exception:** Human mitochondrial DNA (e.g., UGA codes for Tryptophan instead of a Stop codon). * **Non-overlapping & Comma-less:** The code is read sequentially from a fixed starting point without skipping any nucleotides. * **Initiation Codon:** **AUG** (Methionine). In prokaryotes, it codes for N-formylmethionine. * **Stop Codons (Nonsense Codons):** UAA (Ochre), UAG (Amber), UGA (Opal). These do not code for any amino acid.

Forensic Medicine

1 questions

In an act of tribadism, the active partner is known as: (AIIMS 12; COMEDK 14)

Microbiology

1 questions

Which of the following is the aetiological agent most often associated with Epiglottitis in children -

Pharmacology

1 questions

A patient on amphotericin B develops hypokalemia with a potassium level of 2.3 mEq/L. What is the appropriate K+ supplementation required for this patient?

Physiology

1 questions

At what temperature does heat stiffening occur in the body?

About INI-CET 2012 Questions

This page contains 6 questions from the INI-CET 2012 paper, organised across 5 subjects for focused practice. Every question comes with the correct answer and a detailed explanation to help you understand the underlying concept. Subject-wise organisation lets you target specific areas and identify which topics carried the most weight in this particular year.

Practising year-wise papers is essential for understanding how the INI-CET exam evolves — you can spot trending topics, gauge difficulty shifts, and benchmark your readiness against a real paper. To take your preparation further, download the Oncourse app for AI-driven performance insights, spaced repetition of questions you got wrong, and a personalised study plan built around your INI-CET goals.