Level 1
Biology MCQs set 3 for NTS Pakistan Railways Everyday Science — 20 solved questions.
Q1. Copper wires are generally used for electrical power transmission instead of iron wires because:
Answer: Copper is a better conductor than iron
Explanation: Copper has much lower electrical resistivity (~1.68 × 10⁻⁸ Ω·m) than iron (~1.0 × 10⁻⁷ Ω·m), making it a significantly better electrical conductor and reducing energy losses.
Q2. The total number of bones in the human body is what?
Answer: 206
Explanation: 206 is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q3. The vitamin which is generally excreted by humans in urine is:
Answer: Vitamin C
Explanation: Water-soluble vitamins like Vitamin C and B-complex are not stored in the body and are excreted through urine when consumed in excess, unlike fat-soluble vitamins A, D, E, and K.
Q4. The average adult has a blood volume of about:
Answer: 5 liters
Explanation: An average adult human body contains approximately 5 liters of blood, which accounts for about 7-8% of total body weight.
Q5. One cell thick vessels are called:
Answer: Capillaries
Explanation: Capillaries are the smallest blood vessels with walls only one cell thick, enabling efficient exchange of oxygen, nutrients, and waste between blood and surrounding tissues.
Q6. Stimulus intensity is detected in the brain by:
Answer: The number of action potentials per second
Explanation: The brain interprets the intensity (strength) of a stimulus by the frequency of action potentials (nerve impulses per second) arriving along sensory neurons, not by their amplitude.
Q7. All of the following organs in the human body are located on both the right and left sides, except the:
Answer: Spleen
Explanation: The spleen is a single, unpaired organ located only on the left side of the abdomen, unlike kidneys, eyes, and lungs which each occur in bilateral pairs.
Q8. Morphine can cause constipation and a lowering of blood pressure.
Answer: Right
Explanation: Morphine, an opioid, slows gastrointestinal motility causing constipation, and acts on the cardiovascular system to cause vasodilation and a reduction in blood pressure.
Q9. Who discovered blood circulation?
Answer: William Harvey
Explanation: William Harvey is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q10. Blood which the heart pumps to the lungs is:
Answer: Deoxygenated blood
Explanation: The right ventricle of the heart pumps deoxygenated (oxygen-poor) blood to the lungs via the pulmonary artery for oxygenation, completing the pulmonary circuit.
Q11. The monomers of proteins are ____.
Answer: Amino Acids
Explanation: Amino Acids is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q12. Which vitamin gets destroyed by heating?
Answer: C
Explanation: Vitamin C (ascorbic acid) is highly sensitive to heat and oxidation; cooking, boiling, or prolonged heating destroys it rapidly, making it the most heat-labile common vitamin.
Q13. Al-Qanun fi al-Tibb is an encyclopedia of medicine in five books written by:
Answer: Avicenna
Explanation: Al-Qanun fi al-Tibb (The Canon of Medicine) was written by Ibn Sina (Avicenna) in the 11th century and served as a standard medical textbook in Europe and Asia for centuries.
Q14. Solar plates consist of which type of cells?
Answer: Photovoltaic cell
Explanation: Photovoltaic cell is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q15. Red blood cells (RBCs) are also known as:
Answer: Erythrocytes
Explanation: Erythrocytes is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q16. All the metabolic reactions in organisms are catalysed by:
Answer: Enzymes
Explanation: Enzymes are biological catalysts (proteins) that lower the activation energy of metabolic reactions, enabling the thousands of chemical processes that sustain life to occur at body temperature.
Q17. Any disease or infection that is naturally transmissible from vertebrate animals to humans is called:
Answer: Zoonosis
Explanation: Zoonosis is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q18. Ophthalmology is the study of:
Answer: Eyes
Explanation: Ophthalmology is the medical specialty dealing with the anatomy, physiology, and diseases of the eye, practiced by ophthalmologists who perform eye surgery and treat eye conditions.
Q19. Chromosomes are:
Answer: Made up of DNA as a main component
Explanation: Chromosomes are primarily composed of DNA (deoxyribonucleic acid) tightly wound around histone proteins, forming the structural basis for genetic information storage and transmission.
Q20. Which of the following groups of compounds constitute carbohydrates?
Answer: Starch and sugar
Explanation: Carbohydrates are organic compounds made up of carbon, hydrogen, and oxygen; they include monosaccharides and disaccharides (sugars) and polysaccharides (starch, glycogen, cellulose).