Human Body System & Organs MCQs with Answers
Solved Human Body System & 78 Organs MCQs with answers — 206 bones, blood, brain, glands, organs & normal values. Free quiz + PDF for PPSC, FPSC, NTS, CSS & PMS.
Human Body System & Organs — Master Reference for Pakistani Competitive Exams
The chapter Human Body System & Organs is one of the highest-yield Everyday Science topics in Pakistan’s PPSC, FPSC, NTS, CSS, PMS, OTS, CTS, BPSC, KPPSC, SPSC and MDCAT exams. Almost every Junior Clerk, Tehsildar, Assistant, Sub-Inspector, Lecturer and BPS-14 to BPS-17 paper carries 3–5 MCQs from this chapter — and it is core CSS Screening MPT (General Science & Ability) content. This page consolidates 60 solved MCQs covering the 206 bones of the adult skeleton (80 axial + 126 appendicular), blood (5–6 L volume, RBCs, WBCs, platelets, haemoglobin, 13 clotting factors, ABO groups), the brain & nervous system (1.3 kg, cerebrum, motor cortex, medulla, hypothalamus), endocrine glands (master = pituitary, mixed = pancreas, largest = liver), major organs (heart, kidney with ~1 million nephrons, liver, spleen, eye/retina) and normal physiological values (body temp 37 °C, BP 120/80, blood pH 7.35–7.45). For wider context, see Wikipedia: Human Body and the official World Health Organization reference.
Bones, Blood & Vital Numbers — Quick Reference
| Parameter | Value |
|---|---|
| Bones in adult human body | 206 (80 axial + 126 appendicular) |
| Bones in human skull | 28 |
| Vertebrae in spinal column | 33 |
| Pairs of ribs | 12 |
| Adult permanent teeth | 32 |
| Total cells in body | ~37.2 trillion |
| Adult blood volume | 5–6 litres |
| RBC lifespan | 120 days |
| Blood-clotting factors | 13 |
| Brain weight | ~1.3 kg (3 lb) |
| Nephrons per kidney | ~1 million |
| Body temperature | 37 °C / 98.6 °F |
| Normal blood pressure | 120/80 mmHg |
| Blood pH | 7.35–7.45 |
| Iodine in adult body | 15–20 mg (70–80% in thyroid) |
Famous “Anchor Facts” — Most Tested in Exams
- Total bones in adult body — 206.
- Largest cell — Ovum (egg). Longest cell — Neuron. Smallest cell — Sperm.
- Largest organ (external) — Skin (~16% of body weight).
- Largest gland / largest solid organ — Liver.
- Master gland — Pituitary.
- Mixed gland (endocrine + exocrine) — Pancreas.
- Powerhouse of the cell — Mitochondria; brain of the cell — Nucleus.
- Functional unit of kidney — Nephron (~1 million per kidney).
- First organ transplanted (1954) — Kidney.
- Bile made by liver, stored in gallbladder.
- Most digestion & absorption — Small intestine.
- Heart membrane — Pericardium.
- “Graveyard of RBCs” — Spleen.
- Retina = light-sensitive layer of eye, acts like camera film (image is real & inverted).
- Universal donor — O−; universal recipient — AB+.
- ABO gene on chromosome 9. Sex chromosomes: XY = male, XX = female.
- Haemoglobin — iron-containing protein in RBCs (4 subunits, 4 heme groups).
- WBCs fight infection; platelets = blood clotting.
- Hookworm enters through soles of the feet.
- Allergy = antigen-antibody reaction.
- Fertilization in humans occurs in the fallopian tube (oviduct).
- Enzymes = biological catalysts that lower activation energy.
Exam tip: Lock the “numbers anchors” — 206 bones, 33 vertebrae, 12 pairs of ribs, 32 teeth, 5–6 L blood, 13 clotting factors, 1 million nephrons, 1.3 kg brain — these alone cover ~50% of all body-system MCQs in PPSC/FPSC/NTS papers.
Frequently Asked Questions
206 bones — 80 axial (skull, spine, ribs, sternum) and 126 appendicular (limbs and limb girdles).
The ovum (egg cell) is the largest cell in the human body. The neuron is the longest (up to ~1 m), and the sperm is the smallest.
Mitochondria — they produce ATP, the energy currency of the cell.
The pituitary gland — about the size of a pea, sitting in a bony hollow behind the bridge of the nose. It controls many other endocrine glands.
Liver — also the largest solid organ in the human body.
O negative is the universal donor; AB positive is the universal recipient.
Yes — essential. Human body MCQs are tested in every One Paper, NTS NAT, GAT, OTS, CTS, BPSC, KPPSC, SPSC, PPSC and FPSC exam — and core CSS Screening MPT (General Science & Ability) content.
Yes. Click the Download PDF button to get all Human Body System MCQs as a branded QuizWing PDF for offline revision.