CAT 2025 Slot 2 VARC Question Paper with Solution: PDF Download

DIRECTIONS for questions 1-4: The passage below is accompanied by a set of questions. Choose the best answer to each question.

Time and again, whenever a population [of Mexican tetra fish] was swept into a cave and survived long enough for natural selection to have its way, the eyes disappeared. "But it's not that everything has been lost in cavefish . . . Many enhancements have also happened." . . . Studies have found that cave-dwelling fish can detect lower levels of amino acids than surface fish can. They also have more tastebuds and a higher density of sensitive cells alongside their bodies that let them sense water pressure and flow. . . 

Killing the processes that support the formation of the eye is quite literally what happens. Just like non-cavedwelling members of the species, all cavefish embryos start making eyes. But after a few hours, cells in the developing eye start dying, until the entire structure has disappeared. [Developmental biologist Misty] Riddle thinks this apparent inefficiency may be unavoidable. "The early development of the brain and the eye are completely intertwined-they happen together," she says. That means the least disruptive way for eyelessness to evolve may be to start making an eye and then get rid of it. . . . 

It's easy to see why cavefish would be at a disadvantage if they were to maintain expensive tissues they aren't using. Since relatively little lives or grows in their caves, the fish are likely surviving on a meager diet of mostly bat feces and organic waste that washes in during the rainy season. Researchers keeping cavefish in labs have discovered that, genetically, the creatures are exquisitely adapted to absorbing and storing nutrients.

Fats can be toxic for tissues, [evolutionary physiologist Nicolas] Rohner explains, so they are stored in fat cells. "But when these cells get too big, they can burst, which is why we often see chronic inflammation in humans and other animals that have stored a lot of fat in their tissues." Yet a 2020 study by Rohner, Krishnan and their colleagues revealed that even very well-fed cavefish had fewer signs of inflammation in their fat tissues than surface fish do. Even in their sparse cave conditions, wild cavefish can sometimes get very fat, says Riddle. This is presumably because, whenever food ends up in the cave, the fish eat as much of it as possible, since there may be nothing else for a long time to come. Intriguingly, Riddle says, their fat is usually bright yellow, because of high levels of carotenoids, the substance in the carrots that your grandmother used to tell you were good for your...eyes. "The first thing that came to our mind, of course, was that they were accumulating these because they don't have eyes," says Riddle. In this species, such ideas can be tested: Scientists can cross surface fish (with eyes) and cavefish (without eyes) and look at what their offspring are like. When that's done, Riddle says, researchers see no link between eye presence or size and the accumulation of carotenoids. Some eyeless cavefish had fat that was practically white, indicating lower carotenoid levels. Instead, Riddle thinks these carotenoids may be another adaptation to suppress inflammation, which might be important in the wild, as cavefish are likely overeating whenever food arrives.

Question 1: Which one of the following results for the cross between surface fish (with eyes) and cavefish (without eyes) would invalidate Riddle's inference from the experiment?

1. Some offspring with eyes had white fat.

2. Some offspring with eyes had yellow fat.

3. Some eyeless offspring had white fat.

4. Only eyeless offspring had yellow fat. 

Answer: Option 4

Question 2: Which one of the following best explains why the "apparent inefficiency" is "unavoidable"?

1. The lack of light in the caves kills the eye cells in the developing Mexican tetra cavefish embryo.

2. The inefficiency resulting from eyelessness is compensated by enhancements like more tastebuds in Mexican tetra cavefish.

3. Mexican tetra cavefish are similar to non-cave-dwelling variants in their early stages of development.

4. The caves have poor and inconsistent availability of food and nutrition for Mexican tetra cavefish.

Answer: Option 4

Question 3: On the basis of the information in the passage, what is the most likely function of carotenoids in Mexican tetra cavefish?

1. To render bright yellow colour to the cavefish.

2. To act as a substitute for eyes.

3. To help the fat cells store nutrients.

4. To control inflammation from the bursting of fat cells.

Answer: Option 4

Question 4. All of the following statements from the passage describe adaptation in Mexican tetra cavefish EXCEPT:

1. "Since relatively little lives or grows in their caves, the fish are likely surviving on a meager diet of mostly bat feces and organic waste that washes in during the rainy season."

2. "But when these cells get too big, they can burst, which is why we often see chronic inflammation in humans and other animals that have stored a lot of fat in their tissues.'"

3. "It's easy to see why cavefish would be at a disadvantage if they were to maintain expensive tissues they aren't using."

4. "Even in their sparse cave conditions, wild cavefish can sometimes get very fat, says Riddle." 

Answer: Option 2

Listed below is the break up of MCQ and TITA questions in the VARC section of CAT 2025 slot 2 question paper. It was same as Slot 1

Check the below table for the break up of VARC section of CAT 2025 slot 2 question paper difficulty level.

Check below Frequently Asked Questions (FAQs) on CAT Question Paper: