241. In basic biology, which vitamin is essential for normal blood clotting?
✅ C. Vitamin K
a: Vitamin C | b: Vitamin B1 | c: Vitamin K | d: Vitamin D Read more
Biology MCQs – Page 13
242. In basic biology, which cells help defend the body against infection?
✅ D. White blood cells
a: Adipocytes | b: Platelets | c: Red blood cells | d: White blood cells Read more
243. In basic biology, which part of a plant absorbs most water from soil?
✅ C. Roots
a: Flowers | b: Fruits | c: Roots | d: Leaves only Read more
244. In basic biology, which organ is primarily responsible for gas exchange in humans?
✅ B. Lungs
a: Spleen | b: Lungs | c: Gallbladder | d: Heart Read more
245. In basic biology, which pigment gives many plants their green colour?
✅ A. Chlorophyll
a: Chlorophyll | b: Melanin | c: Haemoglobin | d: Keratin Read more
246. In basic biology, which organ filters blood to produce urine?
✅ C. Kidney
a: Stomach | b: Pancreas | c: Kidney | d: Lung Read more
247. In basic biology, which blood type is commonly called the universal red-cell donor in emergency contexts?
✅ A. O negative
a: O negative | b: B negative | c: A positive | d: AB positive Read more
248. In basic biology, which molecule carries hereditary information in most organisms?
✅ D. DNA
a: Cellulose | b: Glucose | c: ATP | d: DNA Read more
249. In basic biology, what is the basic structural and functional unit of life?
✅ D. Cell
a: Organ system | b: Tissue | c: Organ | d: Cell Read more
250. In basic biology, which organelle is often called the powerhouse of the cell?
✅ C. Mitochondrion
a: Lysosome | b: Golgi apparatus | c: Mitochondrion | d: Ribosome Read more
251. Which gas is released by plants during photosynthesis?
✅ C. Oxygen
a: Carbon monoxide | b: Methane | c: Oxygen | d: Ammonia Read more
252. Which process reduces chromosome number to form gametes?
✅ B. Meiosis
a: Mitosis | b: Meiosis | c: Budding | d: Binary fission Read more
253. Which plant tissue transports water upward?
✅ B. Xylem
a: Epidermis | b: Xylem | c: Phloem | d: Cortex only Read more
254. Which plant tissue transports sugars?
✅ D. Phloem
a: Cuticle | b: Xylem | c: Stomata | d: Phloem Read more
255. Which blood component helps form clots?
✅ A. Platelets
a: Platelets | b: Neurons | c: Red blood cells | d: Alveoli Read more
256. Which part of the eye controls the amount of light entering?
✅ A. Iris
a: Iris | b: Optic nerve | c: Retina | d: Cornea only Read more
257. What is the largest organ of the human body?
✅ A. Skin
a: Skin | b: Brain | c: Lung | d: Liver Read more
258. Which structure controls what enters and leaves a cell?
✅ A. Cell membrane
a: Cell membrane | b: Nucleolus | c: Chromosome | d: Cell wall only Read more
259. Which organisms make their own food using sunlight in most ecosystems?
✅ D. Producers
a: Decomposers only | b: Predators | c: Primary consumers | d: Producers Read more
260. Which molecule is the main immediate energy currency of cells?
✅ B. ATP
a: DNA | b: ATP | c: Starch | d: RNA Read more