Level 1
Life Science MCQs set 2 for OTS Water & Sanitation Dept (WSSP / PHED) Everyday Science — 20 solved questions.
Q1. In the hand, there are how many bones?
Answer: 27 bones
Explanation: The human hand contains 27 bones: 8 carpals (wrist), 5 metacarpals (palm), and 14 phalanges (fingers - 3 per finger and 2 for the thumb).
Q2. Leucocytes (white blood cells) are produced in the:
Answer: Bone marrow
Explanation: White blood cells (leukocytes) are produced in the red bone marrow from hematopoietic stem cells, along with red blood cells and platelets.
Q3. Excessive vomiting and diarrhea may result in a decrease of which of the following in the bloodstream?
Answer: Sodium
Explanation: Excessive vomiting and diarrhea cause hyponatremia - loss of sodium through fluid and electrolyte depletion - which can critically affect nerve and muscle function.
Q4. Which viruses are related to the ongoing COVID-19?
Answer: SARS & MERS
Explanation: SARS & MERS is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q5. Electrical activity of the brain is measured by:
Answer: Electroencephalography (EEG)
Explanation: Electroencephalography (EEG) is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q6. A branch of biology dealing with the structure and function of cells is called:
Answer: Cytology
Explanation: Cytology is the branch of biology that examines the structure, function, and chemistry of cells using microscopy and other analytical techniques.
Q7. Which of the following pollutants in water causes "Minamata disease"?
Answer: Methylmercury
Explanation: Minamata disease is severe neurological damage caused by methylmercury poisoning; it was first identified in Minamata, Japan, where industrial wastewater contaminated fish consumed by residents.
Q8. A heart attack is caused due to:
Answer: Cholesterol
Explanation: Excess cholesterol builds up in arterial walls forming plaques (atherosclerosis), narrowing coronary arteries and restricting blood flow to the heart, causing a heart attack.
Q9. When a disease occurs over a large area of the Earth's surface at one time, it is called a:
Answer: Pandemic disease
Explanation: Pandemic disease is the scientifically accurate choice. The concept tested here is core everyday science for MDCAT, ECAT, and general ability papers.
Q10. Which part of the human body is most affected by the hepatitis virus?
Answer: Liver
Explanation: Hepatitis viruses (A, B, C, D, E) primarily infect and damage liver cells (hepatocytes), causing inflammation, jaundice, and potentially cirrhosis or liver failure.
Q11. Which of the following diseases is caused by a virus?
Answer: Smallpox
Explanation: Smallpox is caused by the Variola virus; tuberculosis is bacterial (Mycobacterium), malaria is parasitic (Plasmodium), and cholera is bacterial (Vibrio cholerae).
Q12. 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.
Q13. 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.
Q14. 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.
Q15. 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.
Q16. 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.
Q17. 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.
Q18. 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.
Q19. 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.
Q20. 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.