जीव विज्ञान – Biology MCQ
जीव विज्ञान – कृषि/वन प्रवेश
Biology · Agriculture, Veterinary & Forestry Entrance · ८४० प्रश्न
८४० प्रश्न उपलब्ध। मोड छान्नुहोस्:
जीव विज्ञान: प्रश्न र उत्तर
सही लागेको विकल्पमा थिच्नुहोस्। सही भए हरियो, गलत भए रातो देखिन्छ; ३ सेकेन्डपछि सही उत्तर र व्याख्या देखिन्छ।
सही: ० / ०
-
Which vitamin is required for the synthesis of clotting factors such as prothrombin?
सही उत्तर: ग) Vitamin K
Vitamin K is needed by the liver to make prothrombin and other clotting factors; its deficiency delays blood clotting.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The average life span of human red blood cells is about:
सही उत्तर: ख) 120 days
Human RBCs survive about 120 days, after which they are destroyed mainly in the spleen ('graveyard of RBCs').
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Erythropoietin, the hormone that stimulates formation of red blood cells, is secreted mainly by the:
सही उत्तर: क) Kidneys
The juxtaglomerular cells of the kidney release erythropoietin when oxygen is low, stimulating RBC formation in bone marrow.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The tidal volume of a normal healthy adult at rest is approximately:
सही उत्तर: क) 500 mL
Tidal volume, the air inspired or expired in a normal breath, is about 500 mL (6000-8000 mL per minute).
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The normal blood pressure of a healthy adult human (systolic/diastolic) is about:
सही उत्तर: ग) 120/80 mm Hg
Normal systolic (pumping) pressure is about 120 mm Hg and diastolic (resting) pressure about 80 mm Hg.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Which part of the nephron is impermeable to water but actively transports NaCl out?
सही उत्तर: ग) Ascending limb of loop of Henle
The ascending limb pumps out salts but does not let water follow, so the filtrate becomes dilute and the medulla becomes hypertonic.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
During strenuous exercise, anaerobic respiration in human skeletal muscle produces:
सही उत्तर: क) Lactic acid
When oxygen is short, pyruvate is reduced to lactic acid by lactate dehydrogenase; its build-up causes muscle fatigue.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The net gain of ATP from glycolysis of one glucose molecule (by substrate-level phosphorylation) is:
सही उत्तर: क) 2
Glycolysis makes 4 ATP but uses 2 ATP in the preparatory steps, giving a net gain of 2 ATP (plus 2 NADH).
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
The reaction centre chlorophyll of photosystem II is:
सही उत्तर: ग) P680
Photosystem II has reaction centre P680 (absorption peak 680 nm), while photosystem I has P700.
💬 टिप्पणी / गल्ती रिपोर्ट (०)
-
Which plant hormone is known for delaying leaf senescence by promoting nutrient mobilisation?
सही उत्तर: घ) Cytokinin
Cytokinins delay ageing of leaves by maintaining chlorophyll and protein synthesis (Richmond-Lang effect).
💬 टिप्पणी / गल्ती रिपोर्ट (०)
यी अभ्यास प्रश्न हुन्, आधिकारिक प्रश्न होइनन्। पाठ्यक्रम, विज्ञापन र नतिजाका लागि सम्बन्धित निकायको आधिकारिक वेबसाइट हेर्नुहोस्। उत्तरमा गल्ती भेटे प्रश्नमुनिको "टिप्पणी / गल्ती रिपोर्ट" मा लेख्नुहोस्।
नमस्ते! पाठ्यक्रम, सामान्य ज्ञान, भाषा परीक्षा वा कुनै प्रश्नको उत्तर बुझ्न सोध्नुहोस्।
AI ले गल्ती गर्न सक्छ। महत्वपूर्ण कुरा आधिकारिक स्रोतमा जाँच्नुहोस्।