Class 12 Biology - Organisms and Population MCQs #biologyquiz #class12Biology #eduvictors

Class 12 Biology - Organisms and Population MCQs

Q1. A majority of organisms that are restricted to a narrow range of temperature are called as

(a) stenothermal 

(b) endothermal

(c) ectothermal 

(d) eurythermal

Q2. Most animals are tree-dwellers in a:

(a) Thorn woodland

(b) Temperate deciduous forest

(c) Tropical rainforest

(d) Coniferous forest

Q3. Formation of major biomes such as deserts, rainforest takes place by

(a) rotation of our planet around the sun

(b) tilting our planet to its axis

(c) Both (a) and (b)

(d) seasonal periodicity

Q4. Benthic organisms are affected most by

(a) Water-holding capacity of soil

(b) Light reaching the forest floor

(c) Surface turbulence of water

(d) Sediment characteristics of aquatic ecosystems

Q5. To avoid summer - related problems such as heat and desiccation fish undergoes

(a) hibernation 

(b) diapause

(c) aestivation 

(d) none of these

Q6. According to Allen’s rule, the mammals from colder climates have

(a) shorter ears and longer limbs

(b) longer ears and shorter limbs

(c) longer ears and longer limbs

(d) shorter ears and shorter limbs

Q7. Homeostasis is

(a) the tendency of biological systems to change with change in the environment

(b) the tendency of biological systems to resist change

(c) disturbance of the self-regulatory system and natural controls

(d) biotic materials used in homoeopathic medicines

Q8. In a population unrestricted reproductive capacity is called as:

(a) biotic potential

(b) fertility

(c) carrying capacity

(d) birth rate

Q9. The population is the total number of

(a) interbreeding individuals of a species found in a geographical area

(b) interbreeding individuals of a species found in a different geographical area

(c) Both (a) and (b)

(d) None of the above

Q10. Natality refers to

(a) Death rate

(b) Birthrate

(c) Number of individuals entering a habitat

(d) Number of individuals leaving the habitat

Answer: 

1: (a) stenothermal 

2: (c) Tropical rainforest since the floor is humid and is full of organic waste and insects.

3: (c) Both (a) and (b)

Both rotation and tilt cause annual changes in the intensity and duration of the temperature, resulting in the formation of major biomes like deserts, rainforests and tundra.

4: (d) Sediment characteristics of aquatic ecosystems

5: (c) aestivation 

Aestivation is the cessation or slowing of metabolic activity during the summer period to avoid problems of

heat and desiccation.

6: (d) shorter ears and shorter limbs

7: (b) tendency of biological systems to resist change

8: (a) biotic potential

9: (a) interbreeding individuals of a species found in a geographical area

10: (b) Birthrate

👉See Also:

Biodiversity and Conservation (MCQs)

Biotechnology and Its Applications (Very Short Answer Based Questions - Solved)