Applying critical thinking to the material you have studied can help better retention and understanding. Retention based on clarity of thought about a concept will always be much better. One skill which is a potent tool for diving into critical thinking is the art of questioning? When you start solving a sample question paper, then, even if you do not know the answer, you should be able to give reasons for your choice, which may or may not be correct.

Let us consider an example. Following is a multiple choice question asked in 2011.

Which one of the following aspects is an exclusive characteristic of living things?

(A) Isolated metabolic reactions occur in vitro.

(B) Increase in mass from inside only.

(C) perception of events happening in the environment and their memory.

(D) Increase in mass by accumulation of material both on surface as well as internally.

You can answer an MCQ correctly for three reasons. First, for the reason that you have come across the question and already know the correct choice, second, you can easily rule out the other possibilities (by elimination) and third, you are absolutely sure of the correct answer, based on your study. 

Most student’s strategy to crack the NEET is to go on mindlessly solving MCQ’s with the aim of solving all probable questions that might be asked in the exams. Well, then that may not be of much use.

Let’s apply the critical thinking technique:

Option A given for the said question is based on the assumption that metabolic reactions do not occur outside a living being. Option (A) is incorrect if metabolic reaction in living things does not occur in vitro? But is this true? What about metabolic reactions brought about by enzymes in vitro i.e. in a glass tube? The entire science of biocatalysts in biotechnology is based on exploiting the ability of enzymes to carry out enzymic reactions in vitro, the same reaction which it catalyses in the cell. Both prokaryotic and eukaryotic enzymes can be used in this manner. So can option (A) be the right answer, ‘YES’. 

Option (B) is incorrect if increase in body mass of a living thing can never occur only from inside. Well, here this question does not specify inside of what? If it indicates that the inside of an animal body, then it is not true and if it indicates inside of a cell, then too it is not true. Increase in mass of cells and animals is almost always from inside of the body or a unicellular life and in plant cells, it can be from inside and outside. Or maybe the criteria cannot be applied at all to plant cells. Thus, option (B) also cannot be ruled out as a probable right answer. 

Option (C) is the correct option marked in the book that I have referred to, if all living things perceive events in the environment and register in their memory. This could be true, if all living things have some known mechanism of retaining the memory of events. However, this is not true as bacteria and other multicellular organisms respond to the environment but are not known to have any memory mechanism.

If the increase in mass in living things by accumulation of material both on surface and internally never occurs, Option (D) is incorrect. Again, this can’t be true, as in plants, it is a normal occurrence, where growth i.e. accumulation of material by growth of cell mass can occur both on surface, as well as, internally. The term internally and on the surface is not clearly defined and therefore option (D) too cannot be ruled out as the correct option.

The intention is not to confuse you. This is to highlight the fact that such questions can surface on your question paper. Now if you are confused because you know your science, well then you should not blame yourself. If you have already practised this question, then you may never be confused and will choose the correct option, i.e. (C). If this question did not confuse you, then definitely your approach towards studying requires improvement.

All questions may not be confusing as this one. The problem with this question is many things are assumed, and the language used to explain things is not clear, there is ambiguity (vagueness). Ambiguity is acceptable in social science and not in science. Science is about what is known and definite. The reason for picking up this question is, it is the first question in the book referred to, no other reason.

Therefore, the critical thinking approach while studying your textbook literature or solving MCQ’s is indispensable, of course, if you know how to apply critical thinking? Whatever, pointed out can surely initiate you into critically thinking and how to apply it? I have revealed the first practical secret, the strategy of questioning the question. I will try to explain the concept with more examples in future articles.