Home » Question Bank » Food—Source of Energy for man
General Science

Food—Source of Energy for man

Chapter: Health & Diseases

Question 1 of 5 NDA MCQ

Which one of the following is caused by abacterial pathogen?

Detailed Explanation

Correct Answer

✓ Option D is correct. Typhoid fever is caused by a bacterial pathogen.

📖 Governing Law / Core Concept

Typhoid fever is primarily caused by Salmonella typhi, a Gram-negative bacterium.

🧪 Step-by-Step Breakdown

Typhoid fever transmission occurs through ingestion of contaminated food and water, leading to:

  • High fever
  • Abdominal pain
  • Diarrhea or constipation

The bacterium can survive in water and food, especially in unsanitary conditions.

🔍 Option Analysis

  • AIDS: Caused by the HIV virus (viral pathogen).
  • Dengue fever: Caused by the dengue virus (viral pathogen).
  • COVID-19: Caused by the SARS-CoV-2 virus (viral pathogen).

⚡ Mnemonic / Speed-Run

Remember: "Typhoid is the 'T' in Bacteria" to recall that typhoid is bacterial, while others in the options are viral.

6. Visual Suggestion

6. Visual Suggestion

Include a flowchart illustrating the transmission pathway of Salmonella typhi from contaminated food/water to infected individuals, highlighting symptoms and prevention methods.

📖 Factual Verification & Reference

📖 Factual Verification & Reference:

Verified against NCERT Class 11 Biology, Chapter on Diseases.

Question 2 of 5 NDA MCQ

Which of the following pairs is/are correctly matched?

1. Malaria: Mycobacterium

2. TB: Plasmodium

Select the answer using the code given below:

Detailed Explanation
✓

1. Correct Answer

Option D is correct. [Neither pair is matched correctly]

📖 Core Concept

This question tests knowledge of diseases and their causative agents, specifically identifying the organisms responsible for malaria and tuberculosis.

💡 3. Explanation

Malaria is primarily caused by the parasite Plasmodium, transmitted through the bite of an infected female Anopheles mosquito. It leads to symptoms like fever, chills, and flu-like illness. On the other hand, tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis, transmitted through the air when an infected person coughs or sneezes, causing respiratory issues such as a persistent cough, chest pain, and fever. Hence, both the pairs mentioned in the question are incorrect.

❌ 4. Option Analysis

  • •Option A: Incorrect because malaria is caused by Plasmodium, not Mycobacterium.
  • •Option B: Incorrect because TB is caused by Mycobacterium tuberculosis, not Plasmodium.
  • •Option C: Incorrect because neither of the pairs is matched correctly.
⚡

NDA Speed-Run / Mnemonic Shortcut

Remember: "Plasmodium for Mosquito, Mycobacterium for Cough" helps recall the causative agents for malaria and tuberculosis.

🎯

5. Key Takeaways

Know the primary causative agents of major diseases: Plasmodium for malaria and Mycobacterium tuberculosis for TB.

Question 3 of 5 NDA MCQ

Match List-I with List-II and select the answer using the code given below the lists 

Detailed Explanation

1. Correct Answer

✓

1. Correct Answer

Option C is correct. [Temperature is measured in Kelvin, Weight in Newton, Mass in Kilogram, Pressure in Pascal]

Short Explanation

📖 Short Explanation

This question tests your knowledge of the SI units for different physical quantities like temperature, weight, mass, and pressure.

3. Why Correct Answer is Correct

💡 3. Why Correct Answer is Correct

The reasoning behind the correct option C is based on the International System of Units (SI):

  • Temperature is measured in Kelvin. It's the base SI unit for temperature.
  • Weight is the force exerted by gravity on an object, hence it's measured in Newton, which is the SI unit for force.
  • Mass is the amount of matter in an object, measured in Kilograms. This is the base unit for mass in the SI system.
  • Pressure is the force applied perpendicular to the surface of an object per unit area, measured in Pascal (Pa).

4. Why Other Options are Wrong

❌ 4. Why Other Options are Wrong

  • •Option A: Incorrect because it wrongly lists Newton as the SI unit for weight, Kelvin for temperature, and Pascal for pressure but has no correct options for mass.
  • •Option B: Incorrect as it incorrectly matches Pascal and Newton to wrong quantities without any link to the base units.
  • •Option D: Incorrect as it mistakenly identifies units for mass and weight and pressure without adhering to the SI units mapping.
⚡

NDA Speed-Run / Mnemonic Shortcut

Remember "King Newton Caught Pascal" - Temperature (Kelvin), Weight (Newton), Mass (Kilogram), Pressure (Pascal)

5. Key Learning Point

🎯

5. Key Learning Point

Understanding SI units is crucial for relating physical quantities accurately and is a key concept in physics and engineering examinations.

6. Visual Suggestion

6. Visual Suggestion

Consider a chart diagram aligning each physical phenomenon like temperature, mass, pressure, etc., with their respective SI unit, associating concepts with respective units and symbols for visual learners.

Question 4 of 5 NDA MCQ

The optimum pH at which the enzymes pepsin and trypsin of the human alimentary canal works are

Detailed Explanation

Correct Answer

✓ Option A is correct. Pepsin and trypsin operate optimally in highly differing pH environments.

📖 Governing Law / Core Concept

Pepsin is an enzyme that digests proteins in the acidic environment of the stomach, while trypsin functions in the slightly alkaline conditions of the small intestine.

🧪 Step-by-Step Breakdown

Enzymes are proteins that catalyze biochemical reactions. The activity of enzymes is sensitive to pH, and each enzyme has an optimum pH:

  • Pepsin: Optimum pH = 1.5 - 2.0 (stomach)
  • Trypsin: Optimum pH = 7.5 - 8.0 (small intestine)

In the human alimentary canal:

  • Pepsin functions optimally in an acidic environment (pH ~2), essential for protein digestion in gastric juices.
  • Trypsin functions optimally in a slightly alkaline environment (pH ~8), necessary for protein degradation and absorption in intestinal fluids.

🔍 Option Analysis

Option A: Correct, as it accurately describes the pH range for pepsin and trypsin.

Option B: Incorrect; the pH values are not optimal for either enzyme.

Option C: Incorrect; these pH levels do not match the physiological conditions.

Option D: Incorrect; both enzymes require different pH levels outside of these ranges.

⚡ Mnemonic / Speed-Run

Remember: “2 Protein Gets Peppy” for Pepsin (pH 2) and “76 Tryp Stays Alkaline” for Trypsin (pH 8).

📖 Factual Verification & Reference

📖 Factual Verification & Reference:

Verified against NCERT Class 11 Biology, Chapter 5 (Human Physiology).

Question 5 of 5 NDA MCQ

Iodised salt is a vital part of our diet as it is essential for the synthesis of

Detailed Explanation

Correct Answer

✓ Option B is correct. Iodized salt is vital for synthesizing thyroxine.

📖 Core Biological Concept

Iodine is an essential nutrient that the body uses to produce thyroid hormones, primarily thyroxine (T4), which regulates metabolism and growth.

🧪 Step-by-Step Breakdown

The thyroid gland uses iodine to synthesize two major hormones:

  • Thyroxine (T4) - Contains four iodine atoms, it plays a critical role in metabolic processes.
  • Triiodothyronine (T3) - Contains three iodine atoms, it's more active than T4.

A deficiency in iodine leads to goitre and other metabolic disorders.

🔍 Option Analysis

Estrogen, insulin, and adrenaline are produced by different glands:

  • Estrogen - A hormone mainly produced in the ovaries.
  • Insulin - Produced by the pancreas, regulates blood sugar.
  • Adrenalin - Produced by the adrenal glands, involved in fight-or-flight responses.

⚡ Memory Hook (Mnemonic)

Remember: “Iodine is for Thyroid.” This can help recall that iodine is crucial for producing thyroid hormones.

6. Visual Suggestion

6. Visual Suggestion

A diagram illustrating the thyroid gland, showing the synthesis of thyroxine and triiodothyronine from iodine, highlighting the consequences of iodine deficiency.

📖 Factual Verification & Reference

📖 Factual Verification & Reference:

Verified against NCERT Class 11 Biology, Chapter on Human Physiology.

Unlock 10,000+ Practice Questions

This is a preview of the SenaPrep Question Bank. To access comprehensive chapter-wise exercises, bookmark questions, attempt custom tests, and track your progress, download the official SenaPrep Android App.

Download Android App