Free Kingdom Prokaryotae MCQs with Answers

101. Which part of bacteria is resistant to antibiotics?

• A. Capsule
• B. Slime
• C. Spore
• D. Cell wall

Explanation: In the bacterial cell wall, lying between the outer membrane layer and the cytoplasmic membrane is a site where some species of enzymes called beta-lactamases are present that degrade penicillins and other beta-lactam drugs. The capsule is a gelatinous layer covering the entire bacterium. It plays a role in the adherence of bacteria to human issues. A slime layer is an additional layer that can be produced in ground-dwelling prokaryotes to prevent unnecessary drying due to annual temperature and humidity shifts. Spore formation is a type of asexual reproduction in bacteria. In endospore formation, the bacterium divides within its cell wall, and one side then engulfs the other.

102. Bacteria and fungi are examples of

• A. Producers
• B. Decomposers
• C. Consumers
• D. Denvers

Explanation: Bacteria and fungi are examples of decomposers, and gain energy from breaking down dead organisms or waste from other organisms.

103. Most widespread problem of the antibiotics misuse is the

• A. Rapid cure
• B. Increased resistance in pathogen
• C. Disturbance of metabolism
• D. Immunity

Explanation: Misuse and overuse of antibiotics gives the bacteria more chances to develop resistance to that antibiotic, and this resistance can be shared between different species.

104. Bacterial 'death rate' is equal to 'birth rate; in:

• A. Lag phase
• B. Log phase
• C. Death phase
• D. Stationary phase

Explanation: Option A is incorrect because Lag phase is phase of no growth and bacteria prepare themselves for division.Option B is incorrect because Log phase is the phase of rapid growth, bacteria divide at exponential rate.Option C is incorrect because Death phase is phase in which bacteria start dying, and death rate is more than reproduction rate.Option D is correct since At stationary phase bacterial death rate is equal to reproduction rate.

105. Antibiotics are produced by fungi and certain bacteria of group:

• A. Actinomycetes
• B. Oomycetes
• C. Ascomycetes
• D. Basidiomycetes

Explanation: Antibiotics are synthesized and secreted by certain bacteria (actinomycetes) and fungi. (PTB)

106. Which of the following bacteria have more lipids in their cell wall?

• A. Gram-positive bacteria have more lipids in their cell wall
• B. Gram-negative bacteria have more lipids in their cell wall
• C. Lipids are absent in cell wall of both gram positive and negative bacteria
• D. Both have equal amount of lipids

Explanation: Gram-negative bacteria have a more complex cell wall structure compared to gram-positive bacteria. The outer membrane of gram-negative bacteria contains lipopolysaccharides (LPS), which are lipid-rich molecules. This presence of LPS contributes to a higher lipid content in the cell wall of gram-negative bacteria. In contrast, gram-positive bacteria have a simpler cell wall structure with a thicker layer of peptidoglycan and fewer lipids.

107. When cocci form long chain of cells, the arrangement is termed as:

• A. Staphylococcus
• B. Sarcinae
• C. Streptococci
• D. Cocci

Explanation: Pair of cocci are, called diplococci Rows or chains of cells are called streptococci. Grapelike clusters of cells are staphylococci. Packets of eight or more cells are, sarcinae. Group of four cells in a square arrangement is tetrad.

108. Which type of bacteria has less amount of lipids in them:

• A. Positive bacteria
• B. Negative bacteria
• C. Gram-negative
• D. Gram-positive

Explanation: Gram-positive bacteria have a thick peptidoglycan layer and no outer lipid membrane which gives a positive result in the gram stain test appearing purple. Gram-negative bacteria have a thin peptidoglycan layer and an outer lipid membrane that appears pink.

109. In nitrogen-fixing bacteria, the nitrogenase complex is sensitive to:

• A. O2
• B. CO2
• C. NO2
• D. NO3

Explanation: Nitrogen fixing bacteria contain an enzyme complex known as Nitrogenase which catalyses the conversion of nitrogen gas to ammonia. The nitrogenase complex is sensitive to oxygen. Oxygen will make the enzyme irreversibly inactive. So, the nitrogen-fixing bacteria needs to protect the nitrogenase enzyme from oxygen.

110. Sulphur bacteria belongs to which group of bacteria called

• A. Beta-proteo bacteria
• B. Alpha-proteobacteria
• C. Gamma-proteo bacteria
• D. Delta proteo bacteria

Explanation: Sulfur bacteria belongs to gamma-proteo bacteria which take part in nitrogen and sulfur cycling processes