Read the following passage and answer the next five questions:
In nature, populations of different species in a habitat do not live in isolation but interact in many ways. Depending on the outcome, these interactions between two species are classified as competition, predation and parasitism, commensalism, amensalism and mutualism. Through these interactions trophic energy transfer is facilitated. Some predators help in controlling their prey populations, whereas plants have evolved diverse morphological and chemical defences against herbivores.
Select the incorrect pair in response to abiotic factors:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → We maintain a constant body temperature of 37°C – Conformer
Option (1) We maintain a constant body temperature of 37°C – Conformer — An incorrect pair. An organism that keeps its body temperature constant is a regulator, not a conformer. We sweat in summer and shiver in winter to hold our temperature at 37°C. A conformer, like most animals and nearly all plants, lets its body temperature change with the surroundings.
Option (2) Every winter Keoladeo National Park hosts the birds coming from Siberia – Migration — A correct pair. The birds move away for a time from the cold Siberian winter to a better place, Keoladeo National Park (Bharatpur) in Rajasthan.
Option (3) Under unfavourable conditions many zooplankton species in ponds enter the stage of suspended development – Diapause — A correct pair. Diapause is a stage of suspended development. It lets the zooplankton of lakes and ponds pass the bad season.
Option (4) If a predator is too efficient it overexploits its prey – Extinction — A correct pair. A predator that overexploits its prey can make the prey extinct, and then the predator dies out too for lack of food. This is why predators in nature are ‘prudent’.
Note 1: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
Note 2: This question is from the topic “Responses to Abiotic Factors” in Chapter 13, Organisms and Populations, of the pre-rationalised NCERT book. This portion is not in the present NCERT book, where the chapter is now Chapter 11, Organisms and Populations. The extract below is from the pre-rationalised edition.
NCERT Extract (Pre-rationalised edition, Chapter 13, Organisms and Populations):
Responses to Abiotic Factors – “… (i) Regulate: Some organisms are able to maintain homeostasis by physiological (sometimes behavioural also) means which ensures constant body temperature, constant osmotic concentration, etc. All birds and mammals, and a very few lower vertebrate and invertebrate species are indeed capable of such regulation (thermoregulation and osmoregulation). Evolutionary biologists believe that the ‘success’ of mammals is largely due to their ability to maintain a constant body temperature and thrive whether they live in Antarctica or in the Sahara desert. The mechanisms used by most mammals to regulate their body temperature are similar to the ones that we humans use. We maintain a constant body temperature of 370C.”