Organisms and Populations NEET PYQs (2005–2026) with Solutions

10 solved Organisms and Populations PYQs

Real NEET and AIPMT questions from this chapter, newest first. Try each one, then open the answer and the step-by-step explanation.

1. Question 1 (NEET 2026)

   NEET 2026MediumSex Determination in Honeybees

   Which of the following statements are true with reference to the sex-determination in honeybees? A. An offspring formed from the union of a sperm and egg develops as a female (queen or worker). B. An unfertilized egg develops as a male by parthenogenesis. C. A male has half the number of chromosomes than that of a female. D. Males produce sperms by meiosis. E. Honeybees have a haplodiploid sex-determination system. Choose the correct answer from the options given below :

   1. AOption A: A, B, C and E only
   2. BOption B: B, C, D and E only
   3. COption C: A, B, C and D only
   4. DOption D: A, B, D and E only

   Show answer & explanationHide answer & explanation

   Correct answer: (A) A, B, C and E only

   Explanation

   Honeybees exhibit haplodiploid sex determination. Fertilized eggs develop into diploid females, while unfertilized eggs develop into haploid males by parthenogenesis. Male bees produce sperms by mitosis, not meiosis.

2. Question 2 (NEET 2026)

   NEET 2026MediumPopulation Growth

   Which of the following equations depicts Verhulst-Pearl logistic population growth?

   1. AOption A: Equation 1
   2. BOption B: Equation 2
   3. COption C: Equation 3
   4. DOption D: Equation 4

   Show answer & explanationHide answer & explanation

   Correct answer: (B) Equation 2

   Explanation

   The Verhulst-Pearl logistic growth equation is dN/dt = rN((K−N)/K), where K is carrying capacity, r is intrinsic growth rate and N is population size.

3. Question 3 (NEET 2026)

   NEET 2026EasyPopulation growth: birth and death rates

   Consider a population of 10 million cells. Given the per-capita birth rate of 0.002 (per unit time) and the per-capita death rate of 0.002 (per unit time), the expected number of cells after 10 generations is ______.

   1. AOption A: 1 million
   2. BOption B: 5 million
   3. COption C: 10 million
   4. DOption D: 100 million

   Show answer & explanationHide answer & explanation

   Correct answer: (C) 10 million

   Explanation

   For a population growing exponentially, $$\frac{dN}{dt} = (b - d)N = rN$$ where $b$is the per-capita birth rate and$d$is the per-capita death rate. Here$b = 0.002$and$d = 0.002$, so$r = b - d = 0$. Then$\frac{dN}{dt} = 0$: births exactly balance deaths and the population size does not change, i.e.,$N_t = N_0 e^{rt} = N_0 e^{0} = N_0$. So after 10 generations the population is still 10 million cells, option (C).

4. Question 4 (NEET 2026)

   NEET 2026EasyExponential and logistic growth models

   Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : The logistic growth model of populations is considered more realistic than the exponential growth model. Reason R : Resources are finite. In the light of the above statements, choose the most appropriate answer from the options given below :

   1. AOption A: Both A and R are correct and R is the correct explanation of A
   2. BOption B: Both A and R are correct but R is not the correct explanation of A
   3. COption C: A is correct but R is not correct
   4. DOption D: A is not correct but R is correct

   Show answer & explanationHide answer & explanation

   Correct answer: (A) Both A and R are correct and R is the correct explanation of A

   Explanation

   Exponential growth assumes unlimited resources. NCERT notes that no population in nature has unlimited resources at its disposal to permit exponential growth. Because resources are finite, competition among individuals increases and growth slows, so the population levels off at the carrying capacity (K). This gives the sigmoid curve of the Verhulst-Pearl logistic growth model, which is therefore considered more realistic. So A is correct, R is correct and R explains A, option (A).

5. Question 5 (NEET 2026)

   NEET 2026EasySpecies Interactions

   Which one of the following is an appropriate example of sexual deceit?

   1. AOption A: Female wasp and fig
   2. BOption B: Ophrys and bumblebee
   3. COption C: Sea anemone and clown fish
   4. DOption D: Cuckoo and crow

   Show answer & explanationHide answer & explanation

   Correct answer: (B) Ophrys and bumblebee

   Explanation

   Ophrys orchids mimic female insects to attract male pollinators, an example of sexual deceit.

6. Question 6 (NEET 2026)

   NEET 2026EasyPopulation interactions: competition

   Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Abingdon tortoise in Galapagos islands became extinct within a decade after goats were introduced. Reason R : Goats were more efficient at browsing than Abingdon tortoise. In the light of the above statements, choose the most appropriate answer from the options given below:

   1. AOption A: Both A and R are correct and R is the correct explanation of A
   2. BOption B: Both A and R are correct but R is not the correct explanation of A
   3. COption C: A is correct but R is not correct
   4. DOption D: A is not correct but R is correct

   Show answer & explanationHide answer & explanation

   Correct answer: (A) Both A and R are correct and R is the correct explanation of A

   Explanation

   NCERT gives this as an example of interspecific competition between totally unrelated species: the Abingdon tortoise in the Galapagos Islands became extinct within a decade after goats were introduced on the island, apparently due to the greater browsing efficiency of the goats. So A is correct, and R (goats browsed more efficiently and outcompeted the tortoise for food) is correct and explains A. Hence option (A).

7. Question 7 (NEET 2026)

   NEET 2026EasyPopulation interactions

   Match List-I with List-II. List-I: A. Both species are harmed B. One species is harmed and the other is benefited C. Both species are benefited D. One is benefited while the other has no effect List-II: I. Predation II. Mutualism III. Competition IV. Commensalism Choose the correct answer from the options given below:

   1. AOption A: A-III, B-IV, C-II, D-I
   2. BOption B: A-I, B-II, C-III, D-IV
   3. COption C: A-II, B-I, C-IV, D-III
   4. DOption D: A-III, B-I, C-II, D-IV

   Show answer & explanationHide answer & explanation

   Correct answer: (D) A-III, B-I, C-II, D-IV

   Explanation

   A. In competition both interacting species lose (− −) → III. B. In predation one species benefits (the predator) and the other is harmed (the prey) (+ −) → I. C. In mutualism both species benefit (+ +) → II. D. In commensalism one species benefits and the other is neither harmed nor benefited (+ 0) → IV. So A-III, B-I, C-II, D-IV, option (D).

8. Question 8 (NEET 2026)

   NEET 2026MediumPopulation Attributes

   Choose the correct statements regarding population interactions between two species: A. In both parasitism and commensalism, only one species benefits and the other species is harmed. B. Both species benefit in mutualism. C. Both species benefit in commensalism. D. In parasitism, only one species benefits and the other species is harmed. E. In amensalism, one species is harmed and the other is unaffected.

   1. AOption A: B and E only
   2. BOption B: A and B only
   3. COption C: B, D and E only
   4. DOption D: A and D only

   Show answer & explanationHide answer & explanation

   Correct answer: (C) B, D and E only

   Explanation

   Mutualism benefits both species; parasitism benefits one and harms the other; amensalism harms one species while the other remains unaffected.

9. Question 9 (NEET 2025)

   NEET 2025MediumSpecies Interactions

   Given below are two statements : Statement I : Fig fruit is a non-vegetarian fruit as it has enclosed fig wasps in it. Statement II : Fig wasp and fig tree exhibit mutual relationship as fig wasp completes its life cycle in fig fruit and fig gets pollinated by fig wasp. In light of the above statements, choose the most appropriate answer from the options given below :

   1. AOption A: Both statement I and statement II are correct
   2. BOption B: Both statement I and statement II are incorrect
   3. COption C: Statement I is correct but statement II is incorrect
   4. DOption D: Statement I is incorrect but statement II is correct

   Show answer & explanationHide answer & explanation

   Correct answer: (B) Both statement I and statement II are incorrect

   Explanation

   The fig–fig wasp association is a classic example of mutualism, making statement II correct biologically. However, statement I is incorrect because figs consumed commercially generally do not contain enclosed wasps in the edible fruit.

10. Question 10 (NEET 2025)

    NEET 2025MediumPopulation Growth

    Which one of the following equations represents the Verhulst-Pearl Logistic Growth of population?

    1. AOption A: Option (1)
    2. BOption B: Option (2)
    3. COption C: Option (3)
    4. DOption D: Option (4)

    Show answer & explanationHide answer & explanation

    Correct answer: (B) Option (2)

    Explanation

    The Verhulst-Pearl logistic growth equation is: $$\frac{dN}{dt} = rN\left(\frac{K-N}{K}\right)$$ where N is population size, r is intrinsic rate of increase, and K is carrying capacity.