Free Biodiversity and Variety of Life MCQs with Answers

2901. Plants of this group are called ferns:

• A. Filicinae
• B. Angiospermae
• C. Gymnospermae
• D. All of these options

Explanation: Refer to FTB, Ferns belong to the group Pteropsida, subgroup or class filicinae which are the most abundant group of seedless vascular plants in warm and moist tropical regions.

2902. Curve screw shaped bacteria are known:

• A. Cocci
• B. Bacilli
• C. Spirilla
• D. None of these

Explanation: Spirilla bacteria are also termed curve screw shaped.

2903. In many bacteria cell wall is enclosed within a slime capsule made up of:

• A. Polysaccharides
• B. Cellulose
• C. Amino Acids
• D. Proteins

Explanation: A bacteria consists of glycocalyx- the outermost covering of a bacteria, that exists in two forms i.e., capsule and slime. Glycocalyx is made up of polysaccharides in some cases proteins are also present.

2904. The bacteria can cope unfavourable condition by producing?

• A. Mesosomes
• B. Zygospores
• C. Endospores
• D. Cysts

Explanation: Endospores are dormant bodies that are capable of surviving for longer periods and are resistant to higher temperatures and UV radiations. They stay dormant until they meet the necessary conditions to germinate.

2905. Apparently which bacteria are more resistant to antibiotics?

• A. Gram positive bacteria
• B. Gram negative bacteria
• C. Both Gram positive & negative
• D. None of these

Explanation: In Gram-negative bacteria, periplasmic space - the space between the peptidoglycan layer of the cell wall and cell membrane which is the site of enzymes that degrade antibiotics.

2906. The unique macro-molecule in the bacterial cell wall is:

• A. Polysaccharides
• B. Proteins
• C. Peptidoglycan
• D. Cholesterol

Explanation: Bacterial cell walls are primarily composed of peptidoglycan, which is a unique macromolecule consisting of both sugars (polysaccharides) and amino acids. This gives bacterial cell walls their rigidity and shape.

2907. In bacteria, the resistance against heat is provided by:

• A. Granules
• B. Cysts
• C. Spores
• D. Plasmids

Explanation: Spores are thick, dormant, and tough structures produced by some bacteria that provide resistance or protection against harsh or adverse conditions.They are formed by the bacteria to protect themselves from adverse environmental conditions such as heat, UV rays, nutrient deprivation, presence of toxic chemicals, etc.

2908. The smallest known bacteria belong to the genus:

• A. Mycoplasma
• B. Streplococcus
• C. Escherichia
• D. Bacillus

Explanation: These bacteria lack a cell wall and are among the tiniest free-living organisms.

2909. An example of a bacteria requiring low concentration of oxygen is?

• A. Spirochete
• B. Ecoli
• C. Pseudomonas
• D. Campylobacter

Explanation: Option A: Spirochetes are a diverse group of bacteria that exhibit a helical or spiral shape. While some spirochetes are microaerophilic, many others can tolerate a wide range of oxygen levels.Option B: Escherichia coli (E. coli) is a facultative anaerobic bacterium, meaning it can survive and grow in both the presence and absence of oxygen.Option C: Pseudomonas is a genus of bacteria known for their ability to adapt to a variety of environmental conditions, including aerobic and anaerobic environments. While some species within the genus Pseudomonas are adapted to low-oxygen conditions, many others are capable of aerobic respiration. Option D: Campylobacter is an example of a bacteria that requires a low concentration of oxygen. It is considered a microaerophilic bacterium, meaning it thrives in environments with reduced levels of oxygen. Campylobacter species are commonly found in the gastrointestinal tracts of animals, including birds and mammals, and can cause infections in humans.

2910. The scientist who first reported about microbes was:

• A. Antonie Van Leeuwenhoek
• B. Robert Koch
• C. Louis Pasteur
• D. Twort

Explanation: Option A is the right answer. Leeuwenhoek first discovered microbes and called them animalcules.