Free Kingdom Prokaryotae MCQs with Answers

291. A tetrad is also known as

• A. Bivalent
• B. Duplicated chromosome
• C. Paired homologous chromosome
• D. Homologous and thickened chromosome

Explanation: A tetrad, formed during meiosis, consists of homologous chromosomes paired together.

292. Which one is Monera?

• A. Nostoc
• B. Both 'E. coli' and 'Nostoc'
• C. None of the given options
• D. E. coli - Incorrect. While E. coli is Monera

Explanation: Monera includes all prokaryotic organisms, such as bacteria and cyanobacteria, making both Nostoc and E. coli members of this kingdom.

293. Archaebacteria are mostly likely to occur in

• A. Soil
• B. Ice caps
• C. Freshwater
• D. Hydrothermal vents

Explanation: Archaebacteria, such as thermophiles, thrive in extreme environments like deep-sea hydrothermal vents.

294. In prokaryotes, the genetic material is without:

• A. RNA
• B. DNA
• C. Membrane
• D. Cell membrane

Explanation: In prokaryotes, the genetic material is not enclosed by any membrane. Unlike eukaryotes, which have a true nucleus surrounded by a nuclear membrane, prokaryotes have a nucleoid region where the DNA lies freely suspended in the cytoplasm. There is no nuclear envelope, no membrane-bound nucleus, and no membrane around the DNA, which makes this the correct answer.

295. Bacteria without any flagella is called:

• A. Monotrichous
• B. Amphitrichous
• C. Atrichous
• D. Peritrichous

Explanation: In atrichous bacteria, the cells do not possess flagella, so they are generally non-motile or have alternative means of movement. "Atrichous" is a term used to describe bacteria that lack flagella, which are the whip-like structures used for bacterial motility.

296. These all are the function of flagella in a bacterium but which is the primary one:

• A. Flagellated bacteria can detect chemicals
• B. The flagellated bacteria moves in response to a chemical signal
• C. Help in motility
• D. On some bacteria flagella has a role in immunity

Explanation: The primary function of flagella is to provide motility for microorganisms, allowing them to move through liquid environments. Flagella are whip-like, hair-like, or tail-like appendages that extend from the surface of certain cells, including bacteria, archaea, and some eukaryotic cells.

297. Pilli are hollow, non-helical, filamentous appendages in bacteria. Which one is not true for Pili:

• A. They are involved in mating process
• B. They are the means of attachments of bacteria to various surfaces
• C. They are made up of protein
• D. These are present in gram positive bacteria

Explanation: These are hollow, nonhelical, filamentous appendages. Pili are smaller than flagella and are not involved in motility. True pili are only present in gram-negative bacteria. They are made up of a special protein called pilin. They are primarily involved in a mating process between cells called the conjugation process. Some pili function as a means of attachment of bacteria to various surfaces.

298. The cytoplasmic matrix is the substance present between the plasma membrane and the nucleoid. The plasma membrane and everything present within it is termed as:

• A. Plasmid
• B. Mesosomes
• C. Protoplast
• D. Chromatin body

Explanation: In bacterial cell biology, the term "protoplast" is used to describe the entire cell minus the cell wall. It is often used when referring to Gram-negative bacteria or when the cell wall has been removed. The protoplast includes the plasma membrane, cytoplasm, nucleoid (genetic material), and all other cellular components within the plasma membrane.

299. As we know certain species of bacteria produce spores, these all are the characterstics of a spore except:

• A. Spores can be outside the vegatitive cells
• B. Spores are resistant to adverse environment
• C. Spores may be within the vegetative cells
• D. Spores can never germinate and form vegetative cells

Explanation: Bacterial spores, often referred to as endospores, are a specialized form of reproductive structure formed by certain types of bacteria, primarily within the genera Bacillus and Clostridium. Bacterial spores are highly resistant to adverse environmental conditions, such as heat, desiccation, and radiation. They allow the bacterium to survive in a dormant state until more favorable conditions arise. When conditions become favorable, bacterial spores can germinate, and the spore reverts to its vegetative, actively growing form.

300. If we say that bacteria become dormant, thick-walled, and desiccation resistant during differentiation of vegetative cells which can germinate under suitable conditions. Which structure we are talking about?

• A. Granules
• B. Ribosomes
• C. Cysts
• D. Nucleoid

Explanation: Cysts are protective structures formed by various microorganisms, including some bacteria and protozoa, to help them survive unfavorable environmental conditions. These cysts are typically dormant or resting stages that are more resistant to external stresses and provide a means for the microorganism to wait until conditions improve.