1. Which of the following bacteria forms an endosymbiotic nitrogen fixing association with roots of legumes that helps in Nitrogen Fixation?
- Salmonella
- Staphylococcus
- Clostridium
- Rhizobium
Show Answer
Answer: Rhizobium
Rhizobium is a nitrogen-fixing bacterium that forms a symbiotic relationship with the roots of leguminous plants. This bacterium resides within root nodules and converts atmospheric nitrogen into ammonia through a process known as nitrogen fixation. The ammonia is then further transformed into essential amino acids, providing a valuable nitrogen source to the host plant. This symbiotic association enhances the fertility of the soil and promotes the growth of leguminous crops.
2. Effective TB treatment is difficult because of the unusual structure and chemical composition of which part of the cells of Tuberculosis Bacteria (Mycobacterium tuberculosis)?
- Nucleus
- Plasama
- Cell membrane
- Cell wall
Show Answer
Answer: Cell wall
Tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis, characterized by a unique cell wall composition containing mycolic acids. This distinctive cell wall structure poses challenges for effective treatment as it contributes to the bacterium’s resistance to various antibiotics. TB is a contagious respiratory disease that primarily affects the lungs, and its treatment often involves a prolonged course of multiple antibiotics to target the resilient nature of Mycobacterium tuberculosis.
3. What is the shape of Vibrio bacteria?
- Clusters
- Sticks
- Comma Shaped
- Dot shaped
Show Answer
Answer: Comma Shaped
Vibrio bacteria are characterized by their comma-shaped morphology and are commonly found in specific coastal waters. These bacteria include various species, such as Vibrio cholerae, which is responsible for causing cholera, a waterborne infectious disease. The comma shape of Vibrio bacteria facilitates their movement through water, and their prevalence in coastal environments underscores their ecological significance and potential public health implications.
4. Which bacterial cells are found in cubical packets ?
- Staphylococci
- Sarcinae
- Tetracocci
- Streptococci
Show Answer
Answer: Sarcinae
Sarcina bacteria exhibit a unique arrangement in cubical packets and belong to the genus Clostridiaceae. These bacteria are known for their distinctive cellular morphology, forming packets of cells arranged in a cubic pattern. While Sarcina species are generally harmless, some strains may be associated with health issues, particularly in the context of the gastrointestinal tract.
5. How can Gram Positive Bacteria be identified through Gram staining?
- The Cells membrane has more fatty acids
- The plasma has Peptidoglycans
- The cell walls have more lipids compared to peptidoglycan
- The Cells walls have more Peptidoglycan compared to Lipids
Show Answer
Answer: The Cells walls have more Peptidoglycan compared to Lipids
Gram-positive bacteria, as revealed by the Gram staining technique, retain the violet stain due to the higher peptidoglycan content in their cell walls. This characteristic is a result of the thick peptidoglycan layer present in the cell wall of Gram-positive bacteria, which traps the violet stain. The Gram staining technique is a fundamental tool in microbiology and helps classify bacteria into two major groups based on differences in their cell wall structures—Gram-positive and Gram-negative.
6. Where is the bacterium ‘Escherichia coli’ mainly found?
- Root Nodules of leguminous plants
- Paddy fields for nitrogen fixation
- Human Intestine
- Pteridophytes
Show Answer
Answer: Human Intestine
Escherichia coli, commonly known as E. coli, is a bacterium that resides in the human intestine and is classified as a type of coliform bacterium. While many strains of E. coli are harmless and contribute to the normal flora of the human gut, certain pathogenic strains can cause gastrointestinal infections, leading to symptoms such as diarrhea and abdominal cramps. The presence of coliform bacteria in water is often used as an indicator of fecal contamination.
7. Cholera disease is caused by which type of microorganism?
- Bacteria
- Protozoa
- Fungi
- Virus
Show Answer
Answer: Bacteria
Cholera is a severe diarrheal disease caused by the bacterium Vibrio cholerae. This waterborne pathogen is transmitted through contaminated water or food, particularly in areas with poor sanitation and inadequate access to clean water. Vibrio cholerae produces a toxin that leads to acute diarrhea, dehydration, and, if untreated, can result in severe complications and death. Cholera outbreaks are a significant public health concern, particularly in regions facing challenges related to water and sanitation.
8. Which of the following is not a cause of Food Poisoning?
- E. coli & Shigella
- Yersinia pestis
- Salmonella
- Campylobacter
Show Answer
Answer: Yersinia pestis
Yersinia pestis is the causative agent of plague, a highly infectious and often fatal disease. Unlike food poisoning, Yersinia pestis is primarily transmitted through the bites of infected fleas, which often infest rodents. Plague can manifest in different forms, including bubonic, septicemic, and pneumonic plague. Historically, the bacterium has been responsible for devastating pandemics, such as the Black Death in the 14th century. Although uncommon today, plague remains a concern in some regions.
9. Syphilis is caused by which of the following bacteria?
- Neisseria gonorrhoeae
- Campylobacter
- Treponema pallidum
- Yersinia pestis
Show Answer
Answer: Treponema pallidum
Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. This spirochete bacterium is transmitted through sexual contact, including vaginal, anal, or oral sex. Syphilis progresses through distinct stages, starting with painless sores or ulcers, followed by a rash, and potentially leading to severe complications affecting various organs. Early detection and treatment with antibiotics such as penicillin are crucial to effectively manage and cure syphilis, underscoring the importance of regular screening and safe sexual practices.
10. Which of the following bacteria spreads Plague?
- E. coli & Shigella
- Yersinia pestis
- Salmonella
- Campylobacter
Show Answer
Answer: Yersinia pestis
Plague is a severe infectious disease caused by the bacterium Yersinia pestis. This bacterium is commonly transmitted through the bites of fleas that infest rodents, particularly rats. Plague can manifest in different forms, including bubonic, septicemic, and pneumonic plague. Historically, Yersinia pestis has been responsible for devastating pandemics, such as the Black Death in the 14th century.
11. Whooping cough is caused by which of the following?
- Yersinia pestis
- Treponema pallidum
- Bordetella pertussis
- Helicobacter pylori
Show Answer
Answer: Bordetella pertussis
Whooping cough, or pertussis, is caused by the bacterium Bordetella pertussis. This highly contagious respiratory infection primarily affects the airways, causing severe coughing fits that may be accompanied by a characteristic “whooping” sound during inhalation. Vaccination, particularly in childhood, is crucial for preventing whooping cough and its potentially serious complications.
12. Which of the following is not a form of bacteria?
- Vibrio
- Lobosa
- Coccus
- Bacillus
Show Answer
Answer: Lobosa
Lobosa refers to a taxonomic group of amoeba and is not a form of bacteria. Amoebas are unicellular organisms that belong to the phylum Amoebozoa, and Lobosa is one of the subgroups within this diverse phylum. Amoebas are characterized by their flexible cell membranes and unique method of movement through the formation of pseudopodia.
13. Which of the following is not caused by bacteria?
- Plague
- Chicken pox
- Typhoid
- Tetanus
Show Answer
Answer: Chicken pox
Chickenpox is caused by the varicella-zoster virus (VZV), which is not a bacterium but a virus. Varicella-zoster virus is a member of the herpesvirus family and is highly contagious. Chickenpox typically presents with a characteristic itchy rash, and the infection usually resolves on its own. However, the virus can persist in the body and may later re-emerge as shingles.
14. On which of the following do putrefying bacteria act?
- Carbohydrate
- Vitamins
- Fat
- Protein
Show Answer
Answer: Protein
Putrefying bacteria play a role in the decay of organic matter, particularly proteins. These bacteria are involved in the process of putrefaction, breaking down proteins into simpler compounds, including foul-smelling substances such as amines and sulfides. Putrefaction contributes to the decomposition of organic materials, such as animal carcasses, and is a key aspect of the natural recycling of nutrients in ecosystems.
15. Which bacteria are used in production of biogas/gobar gas plants?
- Propanogens
- N-butane
- Methanogens
- Ethanogens
Show Answer
Answer: Methanogens
Methanogens are crucial microorganisms employed in the production of biogas, commonly known as gobar gas. These anaerobic bacteria play a pivotal role in the anaerobic digestion process, breaking down organic matter in the absence of oxygen and producing methane gas as a byproduct. Biogas plants utilize this methane-rich gas for various purposes, including energy generation.
16. Bacteria used in making of chocolate?
- Monosodium glutamate
- Lactobacillus casei
- Lactobacillus bucheri
- Lactobacillus cacaonum
Show Answer
Answer: Lactobacillus cacaonum
Lactobacillus cacaonum is not a recognized bacterial species; however, various strains of Lactobacillus, such as Lactobacillus plantarum, are employed in the food industry, including chocolate production. Lactobacillus strains contribute to the fermentation process involved in chocolate-making, influencing flavor and texture. The controlled fermentation of cocoa beans by these bacteria is essential for the development of the characteristic taste and aroma of chocolate.
17. Which bacteria are helpful in the Nitrification Process?
- Campylobacter
- Actinomycetes
- Acetobacter
- Nitrosococcus
Show Answer
Answer: Nitrosococcus
Nitrosococcus, Nitrosomonas, Nitrosospira, and related bacteria are integral to the nitrification process in the nitrogen cycle. These bacteria contribute to the conversion of ammonia (NH3) to nitrite (NO2-) and subsequently to nitrate (NO3-). This step is crucial for making nitrogen compounds accessible to plants and plays a key role in nutrient cycling in soil.
18. Which bacteria do not have a cell wall and are therefore resistant to penicillin?
- Bdellovibrios
- Spirochetes
- Cyanobacteria
- Mycoplasmas
Show Answer
Answer: Mycoplasmas
Mycoplasma represents a genus of bacteria characterized by their unique feature of lacking a cell wall. This absence of a rigid cell wall makes them resistant to antibiotics like penicillin, which typically target bacterial cell wall synthesis. Mycoplasma species are known to cause various human and animal infections, and their ability to survive without a cell wall presents challenges in developing effective antibiotic treatments.
19. The protein from which the hooks and filaments of the flagella are made is called?
- Gelatin
- Casein
- Keratin
- Flagellin
Show Answer
Answer: Flagellin
The flagellar hooks and filaments, essential components of bacterial flagella responsible for motility, are composed of a protein called flagellin. Flagella are whip-like appendages that protrude from the bacterial cell surface and are involved in the movement of bacteria towards favorable environments or away from harmful conditions. The structure and composition of flagella, including flagellin, are vital for bacterial motility and chemotaxis.
20. Cocci which are mostly single or in pairs are called?
- Tetracocci
- Diplococci
- Streptococci
- None of these
Show Answer
Answer: Diplococci
Diplococci refer to a specific arrangement of spherical bacteria (cocci) where cells occur mostly in pairs. This distinctive pairing is a characteristic feature observed in microscopic examinations and aids in the identification of certain bacterial species. Examples of bacteria that commonly exhibit a diplococci arrangement include Neisseria species, including Neisseria gonorrhoeae, the causative agent of gonorrhea.
21. Fimbriae can be found in which of the following?
- Both (a) and (b)
- Gram-negative bacteria
- Gram-positive bacteria
- None of these
Show Answer
Answer: Gram-negative bacteria
Fimbriae are short, hair-like structures present on the surface of some Gram-negative bacteria. These structures play a crucial role in bacterial attachment to surfaces, including host tissues. Fimbriae enable bacteria to adhere to specific host cells or other surfaces, facilitating the initiation of infection or colonization. The ability to adhere is a key virulence factor in many pathogenic bacteria.
22. Chemotaxis is a phenomenon of __?
- Swimming away or towards bacteria in the presence of a chemical compound
- All of the above
- Swimming away of bacteria
- Swimming towards bacteria
Show Answer
Answer: Swimming away or towards bacteria in the presence of a chemical compound
Chemotaxis is a biological process involving the movement of bacteria in response to a chemical gradient in their environment. Bacteria sense and respond to changes in chemical concentrations, moving towards attractants or away from repellents. This directional movement allows bacteria to navigate towards favorable conditions or avoid harmful substances, contributing to their survival and adaptation.
23. Which structure is responsible for the motility of bacteria?
- Sheath
- Capsules
- Pili
- Flagella
Show Answer
Answer: Flagella
Flagella are whip-like appendages that protrude from the surface of bacterial cells and are responsible for bacterial motility. The rotation of flagella propels bacteria through liquid environments, facilitating their movement towards nutrients or away from harmful conditions. Flagellar motion is a critical aspect of bacterial behavior, enabling them to explore and navigate their surroundings.
24. Where is teichoic acid commonly found?
- Cell walls of gram-negative bacteria
- Outer membranes of gram-negative bacteria
- Cell walls of gram-positive bacteria
- Outer membranes of gram-positive bacteria
Show Answer
Answer: Cell walls of gram-positive bacteria
Teichoic acid is a component commonly found in the cell walls of Gram-positive bacteria. It is a crucial part of the complex structure of the bacterial cell wall and contributes to its overall stability. Teichoic acid plays a role in cell wall maintenance, regulation of ion movement, and interactions with host cells in Gram-positive bacteria. Its presence is a distinguishing feature between Gram-positive and Gram-negative bacterial cell walls.
25. How many ribosomes are there in eukaryotic cells?
- 80S
- Not specific
- 70S
- 60S
Show Answer
Answer: 80S
Eukaryotic cells contain large ribosomes known as 80S ribosomes within their cytosol. These ribosomes play a crucial role in protein synthesis. The term “80S” refers to the sedimentation coefficient of these ribosomes, indicating their size in comparison to prokaryotic ribosomes. Eukaryotic cells, which include those of plants, animals, fungi, and protists, possess membrane-bound organelles and a defined nucleus, distinguishing them from prokaryotic cells.
26. Porins are located in?
- The cytoplasmic membrane of both gram-negative and gram-positive bacteria
- The periplasmic space of gram-negative bacteria
- The outer membrane of gram-negative bacteria
- The peptidoglycan layer of gram-positive bacteria
Show Answer
Answer: The outer membrane of gram-negative bacteria
Porins are protein channels located in the outer membrane of Gram-negative bacteria. These channels function as selective pores, allowing the passage of certain molecules, such as ions and nutrients, across the bacterial outer membrane. The presence of porins is a characteristic feature of Gram-negative bacteria, which have a double-membrane structure consisting of an outer membrane and an inner membrane.
27. Which of the following is analogous to mesosome of bacteria?
- Lysosomes of eukaryotes
- None of these
- Mitochondria of eukaryotes
- Golgi apparatus of eukaryotes
Show Answer
Answer: Mitochondria of eukaryotes
The mitochondria in eukaryotic cells are analogous to the mesosomes found in bacteria. Both mitochondria and mesosomes are membrane-bound structures involved in energy-related processes. Mitochondria are the powerhouse of eukaryotic cells, playing a central role in cellular respiration and ATP production. Mesosomes, on the other hand, are infoldings of the bacterial plasma membrane, and their exact function remains a subject of scientific debate and investigation.
28. Cyanobacteria have___?
- Neither (a) nor (b)
- No cell wall
- A gram-positive cell wall
- A gram-negative cell wall
Show Answer
Answer: A gram-negative cell wall
Cyanobacteria, despite having certain similarities to Gram-negative bacteria, do not strictly adhere to the Gram classification system. While they possess a double-membrane structure similar to Gram-negative bacteria, their cell walls are more complex. Cyanobacteria have a unique cell envelope with a Gram-negative outer membrane, but their cell wall contains peptidoglycan, a characteristic feature of Gram-positive bacteria. As such, the classification of cyanobacteria based on Gram staining is not entirely straightforward due to their distinct cell wall composition.
29. Which of the following may be most likely to be missing from a gram-positive bacterium?
- Lipopolysaccharide
- Phospholipid bilayer membrane
- Penicillin-binding protein
- Peptidoglycan
Show Answer
Answer: Lipopolysaccharide
Gram-positive bacteria lack lipopolysaccharide in their cell envelope, a component prominently found in the outer membrane of Gram-negative bacteria. The cell envelope of Gram-positive bacteria consists of a thick layer of peptidoglycan, which retains the violet stain during Gram staining, giving them their characteristic purple color. In contrast, Gram-negative bacteria possess a thinner layer of peptidoglycan sandwiched between an inner and outer membrane, with lipopolysaccharide contributing to the structure of the outer membrane.
30. The cocci which form a bunch and irregular pattern are___?
- Tetracocci
- Streptococci
- Staphylococci
- Diplococci
Show Answer
Answer: Staphylococci
Staphylococci are a group of bacteria characterized by their spherical shape (cocci) and their tendency to form irregular clusters. These clusters resemble grapes, with individual cells arranged in a random, non-specific pattern. Staphylococci are Gram-positive bacteria, and some species, such as Staphylococcus aureus, can be pathogenic and are associated with various human infections. The distinctive clustering pattern aids in the identification of staphylococci under a microscope and in laboratory settings.
31. What is the role of pili in bacteria?
- Locomotion
- DNA transfer
- Photosynthesis
- Nutrient absorption
Show Answer
Answer: DNA transfer
Pili are involved in the transfer of genetic material (conjugation) between bacterial cells.
32. Which bacterial shape is characterized by a spherical structure?
- Bacillus
- Spirillum
- Coccus
- Vibrio
Show Answer
Answer: Coccus
Cocci are bacteria with a spherical shape.
33. Which bacterial structure is responsible for genetic variability through mutation?
- Ribosome
- Plasmid
- Nucleoid
- Endospore
Show Answer
Answer: Plasmid
Plasmids can carry genes that confer advantages, and their transfer can contribute to genetic diversity.
34. What is the function of the bacterial capsule?
- Protection
- Locomotion
- DNA storage
- Nutrient absorption
Show Answer
Answer: Protection
The capsule protects bacteria from the host’s immune system and desiccation.
35. Which bacterial process involves the conversion of atmospheric nitrogen into a form usable by plants?
- Nitrogen fixation
- Nitrification
- Denitrification
- Ammonification
Show Answer
Answer: Nitrogen fixation
Nitrogen fixation is the process by which certain bacteria convert atmospheric nitrogen into ammonia.
36. Which bacterial structure is associated with adhesion to surfaces?
- Flagellum
- Pili
- Capsule
- Endospore
Show Answer
Answer: Pili
Pili help bacteria adhere to surfaces, facilitating the formation of biofilms.
37. Which bacterial group is known for its ability to fix nitrogen and form root nodules in plants?
- Cyanobacteria
- Proteobacteria
- Actinobacteria
- Rhizobia
Show Answer
Answer: Rhizobia
Rhizobia form symbiotic relationships with leguminous plants, aiding in nitrogen fixation.
38. Which bacterial process involves the breakdown of complex organic matter into ammonia?
- Nitrification
- Ammonification
- Nitrogen fixation
- Denitrification
Show Answer
Answer: Ammonification
Ammonification is the conversion of organic nitrogen into ammonia.
39. What is the primary function of bacterial plasmids?
- Locomotion
- Antibiotic resistance
- Nutrient absorption
- DNA replication
Show Answer
Answer: Antibiotic resistance
Plasmids often carry genes that provide bacteria with resistance to antibiotics.
40. What is the primary role of bacterial ribosomes?
- Photosynthesis
- Protein synthesis
- DNA replication
- ATP production
Show Answer
Answer: Protein synthesis
Bacterial ribosomes are responsible for synthesizing proteins.
41. Which bacterial group includes the causative agent of tuberculosis?
- Proteobacteria
- Actinobacteria
- Firmicutes
- Spirochaetes
Show Answer
Answer: Actinobacteria
Mycobacterium tuberculosis, the causative agent of tuberculosis, belongs to the Actinobacteria group.
42. What is the primary function of bacterial endospores?
- Locomotion
- Reproduction
- Resistance to harsh conditions
- Nutrient absorption
Show Answer
Answer: Resistance to harsh conditions
Endospores provide bacteria with a high level of resistance to heat, radiation, and chemicals.
43. Which bacterial structure is involved in the exchange of genetic material through horizontal gene transfer?
- Ribosome
- Plasmid
- Pilus
- Nucleoid
Show Answer
Answer: Pilus
The pilus is involved in conjugation, allowing for the transfer of genetic material between bacterial cells.
44. What is the primary role of bacterial spirochetes?
- Nitrogen fixation
- Motility
- Photosynthesis
- Endospore formation
Show Answer
Answer: Motility
Spirochetes are spiral-shaped bacteria known for their unique motility using axial filaments.
