Free Kingdom Prokaryotae MCQs with Answers

321. Arrangement of coccus bacteria in chain is called:

• A. Streptococci
• B. Staphylococci
• C. Tetrad
• D. Sarcina

Explanation: Streptococci is the correct answer. Streptococci refer to a chain-like arrangement of spherical bacteria (cocci). In this arrangement, the cocci divide in one plane, and the resulting daughter cells remain attached to form a chain. The term "strepto" in "streptococci" indicates this linear arrangement.

322. The flagella of bacteria are composed of:

• A. Fibrin
• B. Tubulin
• C. Keratin
• D. Flagellin

Explanation: The flagella of bacteria are composed of flagellin, which is a protein. Flagellin is arranged in a helix, which forms the long, whip-like structure of the flagellum. The flagellum is attached to the cell membrane and the cell wall of the bacterium. Flagellin is a protein that makes up the structural components of flagella, the whip-like appendages that some microorganisms, including bacteria, use for motility (movement). Flagella allow these microorganisms to swim or move through their environment, and flagellin is an essential protein for their function.

323. Which of the following are spiral-shaped bacteria?

• A. Cocci
• B. Bacilli
• C. Pseudomonas
• D. Spirillum

Explanation: A spirillum is a type of bacteria that has a spiral shape. They are typically rod-shaped, but they have a helix that can vary in length and tightness. Spirilla are often motile, meaning that they can move around. They have flagella, which are whip-like structures that help them to move.

324. A bacterial cell, having plasma membrane with all things present within it is called:

• A. Cytoplasmic matrix
• B. Cytoplasm
• C. Protoplast
• D. Cell Structure

Explanation: A bacterial protoplast refers to a bacterial cell that has had its cell wall removed or partially digested, leaving only the cell membrane and cytoplasm. Protoplasts are typically derived from Gram-positive bacteria, as Gram-negative bacteria have an outer membrane that makes the removal of the cell wall more complex.

325. All of the following are characteristics of prokaryotic cells except?

• A. Unicellular
• B. Lack of membrane-bound organelle
• C. Lack of a nucleus
• D. They are found in protists and fungi

Explanation: Prokaryotic cells are not typically found in protists or fungi. Instead, prokaryotic cells are a characteristic of bacteria and archaea. These two domains of life consist of organisms with prokaryotic cells. In prokaryotic cells, the genetic material is not enclosed within a true nucleus and is found in a nucleoid region within the cytoplasm. They lack membrane-bound organelles such as a nucleus, mitochondria, and endoplasmic reticulum, which are features of eukaryotic cells.

326. Which of the following structures helps cyanobacteria to move?

• A. Flagella
• B. Capsule
• C. Gas vesicles
• D. None of these

Explanation: Cyanobacteria, also known as blue-green algae, can exhibit motility through a few different mechanisms, although many species are non-motile. Motility in cyanobacteria, when present, is generally slower and less efficient than that of flagellated bacteria. Some cyanobacteria exhibit gliding motility, while others may perform limited movement via the action of gas vesicles.

327. In Prokaryotes,_are involved in respiration.

• A. Mesosomes and cell membrane
• B. Cell membraneand ribosome
• C. Mesosomes and ribosomes
• D. All of Above

Explanation: The cell membrane regulates the transport of proteins, nutrients, sugar, and electrons or other metabolites. The plasma membranes of bacteria also contain enzymes for respiratory metabolism. Respiratory enzymes are also present on the mesosomes.

328. Methicillin-resistant Staphylococcus aureus is an antibiotic-resistant "superbug" that can cause deadly infections in humans. What would these Gram-positive bacteria look like under a microscope?

• A. Purple spheres
• B. Clear rods
• C. Pink rods
• D. Purple spirals

Explanation: Methicillin-resistant Staphylococcus aureus (MRSA) is a type of Gram-positive bacterium that is resistant to multiple antibiotics, including methicillin and other β-lactam antibiotics. When viewed under a microscope after Gram staining, MRSA appears as Gram-positive cocci(purple spheres).

329. The filamentous appendages called pili are present only on:

• A. Gram-positive bacteria
• B. Gram-negative bacteria
• C. Chemosynthetic bacteria
• D. None of above

Explanation: Pili, are more commonly found in Gram-negative bacteria. While some Gram-positive bacteria may have surface appendages or structures that serve similar functions, true pili are a characteristic feature of many Gram-negative bacteria.

330. Pili are hollow appendages in bacteria that are used for:

• A. Motility
• B. Conjugation
• C. Chemical detection
• D. None of above

Explanation: Based on the explanations provided, the correct answer to the question is option B) Conjugation. Pili in bacteria are used for bacterial conjugation, which involves the transfer of genetic material between bacterial cells.