Free Introduction to Biology MCQs with Answers

91. A cell or individual and its entire asexually produced offspring is called what?

• A. Clone
• B. Mutant
• C. Eugenic organisms
• D. Transgenic organisms

Explanation: The correct answer is "Clone." A clone refers to a cell or organism, along with its entire asexually produced offspring, that is genetically identical to the original. This occurs because asexual reproduction does not involve the combination of genetic material from two distinct cells or organisms, which is the case in sexual reproduction.The other options are incorrect: "Mutant" refers to an organism that has undergone a genetic mutation; "Eugenic organisms" are related to selective breeding practices; and "Transgenic organisms" are genetically modified to include genes from another species.

92. A technology for achieving eugenic aims?

• A. Cloning
• B. Hydroponic culture technique
• C. Bioremediation
• D. Tissue culture technique

Explanation: The correct answer is cloning. Cloning is a technology that can be used to achieve eugenic aims by replicating organisms with desirable traits to create genetically identical copies. It directly manipulates genetic material to ensure specific hereditary outcomes, which aligns with the concept of eugenics. The hydroponic culture technique is focused on plant growth without soil and does not involve genetic manipulation. Bioremediation involves using organisms to clean environmental pollutants and is unrelated to genetic goals. Tissue culture technique is used for growing cells in artificial conditions, often for research, and is not primarily used for eugenic purposes.

93. Commercial production of valuable animals of known pedigree can be done by?

• A. Genetic engineering
• B. Tissue culture technique
• C. Cloning
• D. Gene therapy

Explanation: Cloning is the process of producing genetically identical individuals, which is ideal for the commercial production of valuable animals with a known pedigree. It ensures that the desirable traits of the original animal are preserved in the clone. Genetic engineering involves modifying genes, which may not result in identical animals. Tissue culture is not a method used for animals and is more associated with plant propagation. Gene therapy focuses on treating genetic disorders rather than producing animals with specific pedigrees.

94. Integrated disease management includes what?

• A. Using all methods to combat disease
• B. Participation of community
• C. Both A and B
• D. None of these

Explanation: The correct answer is Option C: 'Both A and B' Integrated disease management is a comprehensive approach that effectively combines various strategies and methods to control diseases. This approach typically involves using a combination of biological, chemical, cultural, and mechanical methods. Community participation is crucial for the successful implementation and sustainability of these strategies, as it ensures that the measures are tailored to local needs and conditions. Options A and B are incomplete because they each cover only one aspect of integrated disease management. Option D is incorrect, as it contradicts the comprehensive nature of this approach.

95. One of the major difficulties in the biological control of insect pests is that:

• A. The method is less effective as compared with the use of insecticides
• B. The practical difficulty of introducing the predator to specific areas
• C. The predator develops a preference for other diets and may itself become a pest
• D. The predator does not always survive when transferred to a new environment

Explanation: Insect enemies play an important role in nature for managing the phytophagous insect pests and keeping a balance. It is just possible that predators of a particular plant pest are unable to get established and multiply in a particular environment. In such cases, the predators are reared in the laboratory and let off at a particular time when the pests are about to threaten the crops. And then this practice becomes expensive.

96. Eliminating bacteria from a living surface using a chemical substance is referred to as:

• A. Antisepsis
• B. Disinfection
• C. Disinfestation
• D. Chemotherapy

Explanation: Antisepsis refers to the use of chemicals on living tissues to kill or inhibit bacteria, preventing infections, particularly in medical settings like surgeries and wound care. In contrast, disinfection applies to non-living surfaces, disinestation is for pest control, and chemotherapy is related to cancer treatment. Unlike these other processes, antisepsis specifically targets infection prevention in living tissue.

97. Which one of the following is not as well-defined in plants as in animals?

• A. Tissues
• B. Organs
• C. Cells
• D. All of these

Explanation: Organs in plants, such as leaves, stems, and roots, are less distinctly defined compared to the highly specialized organs found in animals. In animals, organs are part of complex systems that perform specific functions, whereas in plants, organs are simpler and often perform multiple functions. Tissues and cells are well-defined in both plants and animals, making them incorrect choices.

98. The organ level of organization is much less definite in?

• A. Plants
• B. Animals
• C. Bacteria
• D. Viruses

Explanation: The correct answer is plants. While plants do have organs such as roots, stems, and leaves, their organ systems are not as distinct or specialized as those in animals. This makes the organ level of organization less definite in plants compared to animals.Animals have highly specialized and distinct organ systems, making their organ level of organization more definite. Bacteria are unicellular organisms and do not possess organs; thus, they do not have an organ level of organization at all. Similarly, viruses are not considered living organisms and lack cellular structures, including organs.

99. A group of different tissues organized to perform a function with great efficiency is known as what?

• A. An organism
• B. An organ
• C. Tissue
• D. Population

Explanation: The correct answer is an organ. An organ is a structure made up of different types of tissues that work together to perform a specific function. This differs from a tissue, which is a group of similar cells, and from an organism, which is a complete living being composed of multiple organs and systems. A population refers to a group of the same species in a given area and is not related to tissue organization.

100. The study of organisms living in rivers or lakes is known as what?

• A. Microbiology
• B. Marine Biology
• C. Social Biology
• D. Freshwater Biology

Explanation: The correct answer is freshwater biology. This field specializes in studying organisms that inhabit freshwater environments like rivers and lakes. While microbiology focuses on microorganisms generally, it does not specifically address the freshwater environment. Marine biology is concerned with marine environments such as oceans and seas, not freshwater. Social biology looks at the social behaviors of organisms, which can occur in any environment and are not specific to freshwater ecosystems.