All Free Biology MCQs with Answers

2391. There --- many difficulties regarding the situation.

• A. should
• B. was
• C. were
• D. is

Explanation: The correct answer is 'were' because it matches the plural subject 'difficulties.' The sentence 'There were many difficulties regarding the situation' indicates that multiple challenges existed in the past. The use of 'were' properly reflects the plural nature of the subject. The other options are incorrect because 'should' and 'is' do not fit the required verb form for plural subjects, while 'was' is a singular past tense verb that does not agree with the plural subject 'difficulties.'

2392. Spot the error.The couples have been so close that they even lived next door to each other themselves for a while.

• A. Have been
• B. Even
• C. Each
• D. Themselves

Explanation: The correct answer is Themselves because in this context, the reflexive pronoun 'themselves' is unnecessary. The phrase 'next door to each other' adequately expresses the mutual proximity of the couples, making 'themselves' redundant. The other options are correct in their grammatical form and do not contain errors: 'Have been' appropriately indicates a state of being, 'Even' effectively emphasizes the situation, and 'Each' correctly refers to the couple members.

2393. In this section of logical deduction, the question consists of a brief passage (usually a report containing certain data regarding some social or economic problem), followed by certain inferences based on it. The student is required to analyze the contents (or data) of the passage and grasp the desirable facts from it. Then, student has to consider each of the given inferences in the context of the given passage. decide upon its degree of truth or falsity and then choose the hest alternative provided accordingly.A radical new surgery procedure, laughed at not long ago, is holding out fresh hope for patients of cardiac myopathy, or enlargement of the heart. The technique, now in Pakistan, allows patients to go home two weeks after the Operation, to lead a near-normal sedentary life. Cardiac myopathy is a condition that has a variety of causative factors. An attack from one of the 20 identified viruses, parasite infection, long-term alcohol abuse and blood pressure could bring it on, and in rare cases, it could follow child birth and is even known to run in families. The condition is marked by an increase in the size of the heart's chambers and a decrease in the efficiency of pumping.Cardiac myopathy is hereditary.

• A. Definitely true
• B. Probably true
• C. Data inadequate
• D. Probably false
• E. Definitely false

Explanation: The correct answer is 'Probably true' because the passage states that cardiac myopathy is 'even known to run in families,' suggesting a potential hereditary link. However, it does not provide definitive proof, which is why 'probably true' is more fitting than 'definitely true.' Other options such as 'Data inadequate' and 'Probably false' are less appropriate because the passage does provide some evidence of a hereditary component. 'Definitely false' is incorrect as it contradicts the information given in the passage.

2394. Find the missing term in the sequence: 87, 102, 119, 138, 159, ?

• A. 184
• B. 180
• C. 182
• D. 185

Explanation: The difference between consecutive terms is a sequence of increasing odd numbers: +15, +17, +19, +21. The next difference should be +23. Therefore, the missing term is 159 + 23 = 182.

2395. Passage: A, P, R, X, S and Z are sitting in a row. S and Z are in the centre, and A and P are at the ends. R is sitting on the left of A. Then who is sitting on the right of P?

• A. A
• B. S
• C. X
• D. Z

Explanation: The statement "R is sitting on the left of A" establishes the orientation. If A is at one end and R is to his left, A must be at the right end. This makes P the left end. With S and Z in the center, the only person left to sit between P and the center is X. The order is P, X, (S, Z), R, A.

2396. In the following question, two statements numbered I and II are given. There may be cause and effect relationship between the two statements. These two statements may be the effect of the same cause or independent causes. These statements may be independent causes without saving any relationship. Read both the statements in question and mark your answer as:A. If statement I is the cause and statement II is its effect;B. If statement II is the cause and statement, I is its effect;C. If both the statements I and II are independent causes;D. If both the statements I and II are effects of independent causes;E. If both the statements I and II are effects of some common causes;I. The fanners have decided against selling their kharif crops to the Government agencies.II. The Government has reduced the procurement price of kharif crops starting from last month to the next six months.

• A. A. If statement I is the cause and statement II is its effect;
• B. B. If statement II is the cause and statement I is its effect;
• C. C. If both the statements I and II are independent causes;
• D. D. If both the statements I and II are effects of independent causes;
• E. E. If both the statements I and II are effects of some common cause;

Explanation: Statement II describes a governmental action of reducing procurement prices for kharif crops, which could naturally lead to Statement I, where farmers decide against selling to government agencies due to unfavorable prices. Therefore, Statement II is the cause, and Statement I is its effect. Other options are incorrect because they either misinterpret the causal relationship or suggest independence or a common cause that is not supported by the given information.

2397. In this question, a statement is given followed by two courses of action numbered I and II. It is required to grasp the statement, analyze the problem or policy it mentions and then decide which of the courses of action logically follow / most appropriate.Statement:A large number of people die every year due to drinking polluted water during the summer.Courses of action:I) The government should make adequate arrangements to provide safe drinking water to all its citizens.II) The people should be educated about the dangers of drinking polluted water.

• A. If only I follows
• B. If only II follows
• C. If either I or II follows
• D. If neither I nor II follows
• E. If both I and II follow

Explanation: The correct answer is Option E: If both I and II follow. Providing safe drinking water (Course I) is a direct solution to the problem, ensuring that people have access to non-polluted water. Simultaneously, educating the public about the dangers of drinking polluted water (Course II) ensures that individuals are aware of the risks and can make informed decisions to protect their health. Both actions together create a comprehensive approach to addressing the issue effectively. Relying on only one of these actions may not fully resolve the problem, as education without access to safe water still leaves people vulnerable, and infrastructure without awareness may lead to misuse or negligence.

2398. Which of the following is derived from the host by HIV?

• A. Envelope
• B. RNA
• C. Reverse Transcriptase
• D. All of these

Explanation: The envelope of a virus is derived from the host cell's membrane during the process of viral budding. As enveloped viruses assemble inside the host cell, they acquire a portion of the host's lipid bilayer, which forms the outer envelope surrounding the viral capsid. Viral proteins, such as glycoproteins, are inserted into this membrane before or during budding, allowing the virus to recognize and attach to new host cells. Because the envelope is made from the host cell's own membrane, it helps the virus evade the immune system to some extent, but it also makes enveloped viruses more sensitive to detergents, heat, and drying compared to non-enveloped viruses.

2399. Which event of the life cycle of HIV occurs in the nucleus

• A. Uncoating
• B. Reverse Transcription
• C. Provirus Integration
• D. Assembly

Explanation: The provirus is the integrated viral DNA in the host cell genome, and its formation involves the reverse transcription process in the cytoplasm and integration into the nucleus. Provirus formation is not exclusive to the nucleus.

2400. Adeel observed the given microscopic view of a permanent slide in the laboratory. The CORRECT identification and the reason for identification is

• A. A
• B. B
• C. C
• D. D

Explanation: Paramecium is slipper shaped which matches the figure, so option D is correct. Euglena is spindle shaped and elongated with tapered anterior and posterior ends, which does not match the picture. So A and B are incorrect. Option C gives wrong description of Paramecium.