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NCERT Based Biology MCQ, 11th Class
NCERT Based MCQ with Explanation:
1. What is the primary condition for condensation in the atmosphere?
(a) Increase in air temperature
(b) Decrease in air temperature
(c) Increase in air volume
(d) Decrease in moisture content
Explanation: Condensation occurs when air temperature decreases, causing water vapor to reach its dew point and form liquid droplets or ice crystals.
2. Which form of condensation occurs when moisture is deposited as water droplets on solid objects?
(a) Frost
(b) Dew
(c) Fog
(d) Clouds
Explanation: Dew forms when moisture condenses as water droplets on cooler surfaces like grass or stones, typically under clear skies and calm conditions.
3. What is the key difference between fog and mist?
(a) Fog contains more moisture than mist
(b) Mist contains more moisture than fog
(c) Fog forms at higher altitudes
(d) Mist is mixed with smoke
Explanation: Mist has a thicker layer of moisture around each nucleus compared to fog, which is drier.
4. Which type of cloud is formed at altitudes of 8,000–12,000 meters?
(a) Cumulus
(b) Stratus
(c) Cirrus
(d) Nimbus
Explanation: Cirrus clouds are high-altitude clouds, thin and feathery, forming at 8,000–12,000 meters.
5. What is the term for precipitation in the form of fine snow flakes?
(a) Rainfall
(b) Sleet
(c) Snowfall
(d) Hail
Explanation: Snowfall occurs when precipitation takes the form of fine snow flakes at temperatures below 0°C.
6. Which type of rainfall is associated with air rising over mountains?
(a) Convectional
(b) Orographic
(c) Cyclonic
(d) Frontal
Explanation: Orographic rainfall occurs when moist air is forced to rise over mountains, cooling and condensing to produce rain.
7. What is the term for the area on the leeward side of a mountain that receives less rainfall?
(a) Windward slope
(b) Rain-shadow area
(c) Convection zone
(d) Cyclonic belt
Explanation: The leeward side of a mountain, where air descends and warms, receives less rainfall, known as the rain-shadow area.
8. Which cloud type is characterized by a flat base and cotton wool appearance?
(a) Cirrus
(b) Cumulus
(c) Stratus
(d) Nimbus
Explanation: Cumulus clouds resemble cotton wool, have a flat base, and form at 4,000–7,000 meters.
9. What is the primary source of nuclei for condensation in fog?
(a) Water vapor
(b) Dust and smoke particles
(c) Nitrogen gas
(d) Oxygen molecules
Explanation: Fog forms when water vapor condenses around fine dust, smoke, or salt particles acting as nuclei.
10. Which form of precipitation consists of frozen raindrops?
(a) Snow
(b) Sleet
(c) Hail
(d) Dew
Explanation: Sleet is formed when raindrops freeze into small ice pellets as they pass through a subfreezing layer near the ground.
NCERT Based Biology 12th MCQ11. What condition is necessary for dew formation?
(a) Dew point below freezing
(b) Dew point above freezing
(c) High wind speed
(d) Low relative humidity
Explanation: Dew forms when the dew point is above the freezing point, allowing moisture to condense as liquid droplets.
12. Which cloud type is black or dark gray and associated with heavy rain?
(a) Cirrus
(b) Cumulus
(c) Stratus
(d) Nimbus
Explanation: Nimbus clouds are dense, dark, and associated with heavy precipitation, often forming near the ground.
13. What causes convectional rainfall?
(a) Air rising over mountains
(b) Heated air rising in convection currents
(c) Collision of warm and cold air masses
(d) Descending air masses
Explanation: Convectional rainfall occurs when heated air rises, expands, cools, and condenses to form cumulus clouds and rain.
14. Which regions receive the highest annual rainfall?
(a) Polar regions
(b) Equatorial belt and windward slopes
(c) Interior continental areas
(d) High latitude deserts
Explanation: The equatorial belt and windward slopes in temperate zones receive over 200 cm of rainfall annually due to high moisture availability.
15. What is the primary factor influencing the global distribution of rainfall?
(a) Altitude
(b) Latitude
(c) Soil type
(d) Vegetation
Explanation: Rainfall decreases from the equator to the poles, influenced by latitude and atmospheric circulation patterns.
16. Which form of condensation is most likely to reduce visibility to zero?
(a) Dew
(b) Frost
(c) Fog
(d) Clouds
Explanation: Fog, being a cloud near the ground, can significantly reduce visibility, sometimes to zero.
17. What type of cloud is associated with extensive vertical development?
(a) Cirrus
(b) Stratus
(c) Cumulonimbus
(d) Altostratus
Explanation: Cumulonimbus clouds have extensive vertical development, often leading to thunderstorms and heavy rain.
18. Which condition favors frost formation?
(a) Dew point above freezing
(b) Dew point at or below freezing
(c) High relative humidity and strong winds
(d) Clear skies and high temperatures
Explanation: Frost forms when condensation occurs at or below 0°C, depositing ice crystals on surfaces.
19. What is the term for a mixture of fog and smoke?
(a) Mist
(b) Smog
(c) Haze
(d) Dew
Explanation: Smog is a combination of fog and smoke, common in urban areas with high pollution.
20. Which type of rainfall is common in equatorial regions?
(a) Orographic
(b) Cyclonic
(c) Convectional
(d) Frontal
Explanation: Convectional rainfall is prevalent in equatorial regions due to intense heating and rising air currents.
21. What is the primary source of moisture for precipitation over oceans?
(a) Evaporation from land
(b) Evaporation from ocean surfaces
(c) Transpiration from plants
(d) Melting of ice caps
22. Which cloud type covers large portions of the sky in layers?
(a) Cirrus
(b) Cumulus
(c) Stratus
(d) Nimbus
23. What is the term for precipitation in the form of rounded ice pieces?
(a) Sleet
(b) Snow
(c) Hail
(d) Frost
24. Which factor contributes to the formation of cirrus clouds?
(a) Low altitude and high moisture
(b) High altitude and low temperature
(c) High temperature and strong winds
(d) Low humidity and calm air
25. What is the main characteristic of orographic rainfall?
(a) Heavy rainfall on leeward slopes
(b) Greater rainfall on windward slopes
(c) Uniform rainfall across all slopes
(d) Rainfall due to cyclonic activity
26. Which type of cloud is most likely to cause thunderstorms?
(a) Cirrus
(b) Cumulonimbus
(c) Stratus
(d) Altostratus
27. What is the primary cause of snowfall?
(a) Condensation above freezing point
(b) Condensation below freezing point
(c) Evaporation of water vapor
(d) Melting of hailstones
28. Which regions experience moderate rainfall of 100–200 cm annually?
(a) Equatorial belt
(b) Interior continental areas
(c) Polar regions
(d) Rain-shadow zones
29. What is the role of dust particles in fog formation?
(a) They absorb moisture
(b) They act as condensation nuclei
(c) They increase air temperature
(d) They reduce humidity
30. Which type of rainfall is associated with the collision of air masses?
(a) Convectional
(b) Orographic
(c) Cyclonic
(d) Relief
31. What is the appearance of cirrus clouds?
(a) Thick and dark
(b) Thin and feathery
(c) Layered and flat
(d) Puffy and white
32. Which form of precipitation is sporadic and limited in occurrence?
(a) Rainfall
(b) Snowfall
(c) Hail
(d) Dew
33. What is the primary factor for the formation of cumulus clouds?
(a) Cooling of air at high altitudes
(b) Heating of air at the surface
(c) Mixing of air masses
(d) Descending air currents
34. Which cloud type is most likely to form on clear, sunny days?
(a) Stratus
(b) Nimbus
(c) Cumulus
(d) Cirrostratus
35. What is the main difference between sleet and hail?
(a) Sleet is larger than hail
(b) Hail forms in warmer conditions
(c) Sleet is frozen raindrops, hail is layered ice
(d) Sleet forms in cumulonimbus clouds
36. Which condition is least favorable for dew formation?
(a) Clear skies
(b) High relative humidity
(c) Strong winds
(d) Cold nights
37. What is the primary source of moisture for clouds?
(a) Condensation of nitrogen
(b) Evaporation of water vapor
(c) Melting of ice crystals
(d) Transpiration from plants
38. Which type of cloud is opaque to sunlight?
(a) Cirrus
(b) Cumulus
(c) Stratus
(d) Nimbus
39. What is the term for clouds formed at middle altitudes?
(a) Cirrostratus
(b) Altostratus
(c) Stratocumulus
(d) Cumulonimbus
40. Which factor contributes to the low rainfall in rain-shadow areas?
(a) High humidity
(b) Descending, warming air
(c) Rising, cooling air
(d) Cyclonic activity
41. What is the primary cause of cyclonic rainfall?
(a) Heating of air at the surface
(b) Collision of air masses
(c) Air rising over mountains
(d) Evaporation from oceans
42. Which cloud type is associated with fair weather?
(a) Nimbus
(b) Cumulus
(c) Stratus
(d) Cirrostratus
43. What is the term for the process of water vapor turning into liquid droplets?
(a) Evaporation
(b) Condensation
(c) Precipitation
(d) Transpiration
44. Which regions receive the least rainfall annually?
(a) Equatorial belt
(b) Rain-shadow zones and high latitudes
(c) Coastal areas
(d) Temperate zones
45. What is the primary factor for the formation of nimbus clouds?
(a) High altitude and low humidity
(b) Low altitude and high moisture
(c) Clear skies and calm air
(d) Strong winds and low temperature
46. Which type of precipitation is associated with thunderstorms?
(a) Sleet
(b) Hail
(c) Snow
(d) Dew
47. What is the main characteristic of stratus clouds?
(a) Feathery and thin
(b) Layered and widespread
(c) Puffy and white
(d) Dark and dense
48. Which condition is necessary for frost to form instead of dew?
(a) Air temperature above freezing
(b) Air temperature at or below freezing
(c) High wind speed
(d) Low relative humidity
49. What is the primary source of nuclei for cloud formation?
(a) Nitrogen molecules
(b) Dust and salt particles
(c) Oxygen atoms
(d) Water droplets
50. Which type of rainfall is short-lived but heavy?
(a) Orographic
(b) Cyclonic
(c) Convectional
(d) Frontal