Free Kingdom Prokaryotae MCQs with Answers

201. Cell wall of gram-positive bacteria is composed of:

• A. Glycolipids
• B. Glycoproteins
• C. Lipoproteins
• D. Peptidoglycan

Explanation: Bacterial cell walls are made of peptidoglycan, also called as murein, which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids.

202. Many bacteria are motile due to presence of:

• A. Flagella
• B. Pilli
• C. Cilia
• D. Microtubules

Explanation: "The explanation for this question will be added soon!".

203. Cell wall is only absent in:

• A. Archaeobacteria
• B. Eubacteria
• C. Mycoplasma
• D. Cyanobateria

Explanation: Mycoplasmas are a group of bacteria that are characterized by their lack of a cell wall, which makes them unique among bacteria. They belong to the class Mollicutes. Mycoplasmas are some of the smallest known free-living organisms and have a simple cell structure.

204. Moist heat cause_and kill the microbes:

• A. Oxidation of proteins
• B. Coagulation of proteins
• C. Degeneration of nucleic acids
• D. Bursting up of cells

Explanation: Moist heat can cause the coagulation or denaturation of proteins. When proteins are exposed to high temperatures, their three-dimensional structure can be disrupted, leading to the loss of their functional shape. This process is often irreversible and causes the proteins to form clumps or solidify, which can be detrimental to the survival of microbes. The coagulation of proteins can result in the inactivation or destruction of essential microbial enzymes and structures, ultimately killing the microbes. In summary, moist heat primarily causes the coagulation of proteins, which leads to the inactivation of microbial enzymes and structures, ultimately killing the microbes. While the degeneration of nucleic acids and the bursting of cells can also occur, they are generally secondary effects in the context of microbial death caused by moist heat.

205. Diameter of E. coli is_ to_ micrometer:

• A. 0.5-1.5
• B. 2.0-4.0
• C. 1.1-1.6
• D. 2.0-6.0

Explanation: The diameter of E. coli falls within the range of 1.1 to 1.5 micrometers. E. coli is a bacterium, and its typical size can vary depending on various factors such as growth conditions and strain. On average, E. coli cells are approximately 1-2 micrometers long and 0.5-1 micrometer in diameter. The given range of 1.1-1.5 micrometers falls within the expected diameter range of E. coli. In summary, option A) 1.1-1.5 micrometers is the most accurate choice for the diameter range of E. coli, based on its typical size.

206. Killing bacteria from a living surface by using some chemical substance is called:

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

Explanation: Antisepsis refers to the process of killing or inhibiting the growth of microorganisms, particularly bacteria, on living surfaces such as the skin or mucous membranes. Antiseptics are chemical substances that are applied to living tissues to achieve this purpose. Examples of antiseptics include iodine, and alcohol. Antisepsis is commonly used in medical settings to prevent infections during surgical procedures or to clean wounds.

207. Pick up the component which is comparatively in greater amount in Gram -ve cell wall:

• A. Lipids
• B. Peptidoglycan
• C. Teichoic acid
• D. Lipoteichoic acid

Explanation: "The explanation for this question will be added soon!".

208. DNA of bacteria is present in:

• A. Nucleoid
• B. Nucleus
• C. Mitochondria
• D. Mesosome

Explanation: The DNA of bacteria is present in the nucleoid. The nucleoid is a distinct region within the bacterial cell where the genetic material (chromosomal DNA) is located. Unlike eukaryotic cells, bacteria do not have a membrane-bound nucleus, so their genetic material is dispersed within the nucleoid region.

209. Antibiotics act against:

• A. Bacterial diseases
• B. Allergies
• C. Viral Diseases
• D. Bacterial and Viral Diseases

Explanation: Antibiotics are medications that are used to treat bacterial infections. They work by killing or preventing the growth of bacteria. Antibiotics do not work against viruses, fungi, or parasites. Antibiotics are medications specifically designed to treat bacterial infections and diseases. They work by targeting and killing bacteria or inhibiting their growth. Antibiotics are not effective against viral infections, such as the common cold or flu, as viruses are different from bacteria in terms of their structure and replication mechanisms.

210. It is responsible for drug resistance in bacteria:

• A. Slime
• B. Plasmid
• C. Capsule
• D. Pili

Explanation: Plasmids can be responsible for drug resistance in bacteria. Plasmids are small, circular pieces of DNA that can be found in bacteria. They are not essential for the survival of bacteria, but they can carry genes that confer resistance to antibiotics.