Types Of Microorganisms! Hardest Trivia Quiz

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By Tammychoe
T
Tammychoe
Community Contributor
Quizzes Created: 1 | Total Attempts: 1,002
| Attempts: 1,002 | Questions: 72
Please wait...
Question 1 / 72
0 %
0/100
Score 0/100
1. Disease-causing microorganisms are called

Explanation

Pathogens are disease-causing microorganisms. They are able to invade and multiply within the host, causing various infections and diseases. Pathogens can be bacteria, viruses, fungi, or parasites. They have specific mechanisms and virulence factors that allow them to evade the host's immune system and cause harm. Identifying and understanding pathogens is crucial in the field of medicine to develop effective treatments and preventive measures against infectious diseases.

Submit
Please wait...
About This Quiz
Types Of Microorganisms! Hardest Trivia Quiz - Quiz

Explore the challenging world of microorganisms with our 'Types of Microorganisms! Hardest Trivia Quiz'. Delve into the roles and characteristics of microbes, including pathogens, decomposers, and prokaryotes, and their applications in biotechnology. Ideal for enhancing understanding in microbiology.

2. The microorganisms that recycle nutrients by breaking down dead matter and wastes are called

Explanation

Decomposers are microorganisms that play a crucial role in ecosystems by breaking down dead matter and wastes. They break down organic material into simpler forms, releasing nutrients back into the environment. This process, known as decomposition, is essential for nutrient cycling and the overall health of the ecosystem. Prokaryotes are a type of microorganism that lack a nucleus, but not all prokaryotes are decomposers. Fermenters are microorganisms that carry out fermentation, a metabolic process that does not involve oxygen, but they are not specifically involved in nutrient recycling. Pathogens are microorganisms that cause diseases and are not involved in the decomposition process.

Submit
3. The microorganisms that do not have a nucleus in their cell wall are called

Explanation

Prokaryotes are microorganisms that do not have a nucleus in their cell wall. They are single-celled organisms that lack membrane-bound organelles, including a nucleus. Prokaryotes include bacteria and archaea. They have a simple cellular structure and are capable of various functions such as decomposition, nitrogen fixation, and photosynthesis. Unlike eukaryotes, which have a nucleus and other membrane-bound organelles, prokaryotes have their DNA floating freely in the cytoplasm. Therefore, prokaryotes are the correct answer to the question.

Submit
4. The Dutch merchant who made and used quality magnifying lenses to see and record microorganisms was

Explanation

Leeuwenhoek is the correct answer because he was a Dutch merchant who made and used quality magnifying lenses to see and record microorganisms. He is considered one of the pioneers of microbiology and is known for his meticulous observations and accurate drawings of microorganisms, which he made using his handmade lenses. His discoveries greatly contributed to the understanding of the microscopic world and laid the foundation for the field of microbiology.

Submit
5. Koch's postulates are criteria used to establish that 

Explanation

Koch's postulates are criteria used to establish that a specific microbe is the cause of a specific disease. These postulates were developed by Robert Koch and are still widely used in microbiology to determine the causative agent of a disease. According to Koch's postulates, the microbe must be present in all cases of the disease, it must be isolated from the diseased individual and grown in pure culture, it should cause the same disease when inoculated into a healthy individual, and it must be re-isolated from the newly infected individual. These steps help establish a causal relationship between a specific microbe and a specific disease.

Submit
6. The outcome of the gram stain is based on differences in cell's 

Explanation

The outcome of the gram stain is based on differences in the cell wall. Gram staining is a technique used to differentiate bacteria into two groups: Gram-positive and Gram-negative. Gram-positive bacteria have a thick peptidoglycan layer in their cell wall, which retains the crystal violet stain, giving them a purple color. On the other hand, Gram-negative bacteria have a thinner peptidoglycan layer and an outer membrane, which does not retain the stain, resulting in a pink color. Therefore, the cell wall plays a crucial role in determining the outcome of the gram stain.

Submit
7. The fossil record has est. that prokaryotes existed on earth for approx 2 billion years before eukaryotes appeared

Explanation

The explanation for the given correct answer is that the fossil record, which consists of preserved remains or traces of organisms from the past, has provided evidence that prokaryotes, which are single-celled organisms without a nucleus, existed on Earth for approximately 2 billion years before eukaryotes, which are organisms with a nucleus, appeared. This evidence supports the statement that the given statement is true.

Submit
8. Which activity is an example of biotechnology?

Explanation

Using yeast to make beer and wine is an example of biotechnology because it involves the use of living organisms, in this case yeast, to produce a desired product. Biotechnology refers to the use of biological systems, organisms, or their components to develop or create useful products or processes. In this case, yeast is used to ferment sugars and produce alcohol, which is then used to make beer and wine.

Submit
9. Microorganisms are best defined as organisms that 

Explanation

Microorganisms are best defined as organisms that are too small to be seen with the unaided eye. This definition encompasses a wide range of microscopic organisms such as bacteria, viruses, fungi, and protozoa. These organisms play a crucial role in various ecosystems and have both beneficial and harmful effects on human health and the environment.

Submit
10. These bacteria are small gram neg, obligate intracellular parasites and they tend to alternate between two forms elementary body and reticulate body

Explanation

Chlamydia is the correct answer because it matches the given description of being small, gram-negative, obligate intracellular parasites that alternate between two forms - elementary body and reticulate body. Chlamydia is a genus of bacteria that includes several species known to cause various infections in humans and animals.

Submit
11. The primary purpose of staining cells on a microscope slide is to

Explanation

Staining cells on a microscope slide is done to add contrast, which helps in visualizing the cells better. By using specific dyes or stains, the cells can be highlighted and differentiated from their surroundings, making it easier to observe their structure, morphology, and any abnormalities. This contrast enhancement enables researchers and scientists to study and analyze cells more effectively under a microscope.

Submit
12. _____ organelles in algae and plants are known to have evolved from cyanobacteria by the process of endosymbiosis.

Explanation

Chloroplasts in algae and plants are believed to have evolved from cyanobacteria through endosymbiosis. Endosymbiosis is a process where one organism lives inside another and both benefit from the relationship. In this case, it is believed that cyanobacteria were engulfed by a host cell and eventually became chloroplasts. This theory is supported by the fact that chloroplasts have their own DNA, similar to cyanobacteria, and can carry out photosynthesis, a process that cyanobacteria are also capable of. Therefore, the correct answer is chloroplast.

Submit
13. What is the correct sequence for gram stain?

Explanation

The correct sequence for the gram stain is crystal violet, gram's iodine, alcohol, safranin. This staining technique is used to differentiate bacteria into two groups: gram-positive and gram-negative. Crystal violet is the primary stain that colors all bacteria purple. Gram's iodine is the mordant that forms a complex with crystal violet, making it more resistant to decolorization. Alcohol is the decolorizing agent that removes the crystal violet-iodine complex from gram-negative bacteria, leaving them colorless. Safranin is the counterstain that stains gram-negative bacteria pink, allowing them to be differentiated from the gram-positive bacteria.

Submit
14. Why is immersion oil often used when viewing specimens under the microscope

Explanation

Immersion oil is often used when viewing specimens under the microscope to increase the resolution. Immersion oil has a similar refractive index as glass, which reduces the amount of light that is scattered or refracted as it passes through the specimen and the microscope lens. This reduction in scattering and refraction allows more light to be collected by the lens, resulting in a clearer and more detailed image. By using immersion oil, the resolution of the microscope is improved, allowing for better visualization and analysis of the cells or organisms being observed.

Submit
15. This bacterium causes a commonly acquired sexually transmitted bacterial disease and Trachoma, the most common cause of blindness

Explanation

Chlamydia is the correct answer because it is a bacterium that is known to cause both a commonly acquired sexually transmitted bacterial disease and Trachoma, which is the most common cause of blindness. Chlamydia is transmitted through sexual contact and can cause infections in the genital tract, leading to symptoms such as discharge, pain, and infertility. Additionally, if left untreated, Chlamydia can spread to the eyes and cause Trachoma, a chronic infection that can lead to blindness. Therefore, Chlamydia fits the description provided in the question.

Submit
16. Which bacterium was the first organisms to produce oxygen as a byproduct of photosynthesis

Explanation

Cyanobacteria were the first organisms to produce oxygen as a byproduct of photosynthesis. They are a group of bacteria that are capable of photosynthesis and have the ability to convert sunlight into energy. Through this process, they release oxygen into the atmosphere, which played a crucial role in the evolution of life on Earth. Cyanobacteria are often referred to as blue-green algae, but they are not true algae. They are found in various environments, including freshwater, marine, and terrestrial habitats.

Submit
17. Spontaneous generation is the belief that

Explanation

The belief of spontaneous generation states that living organisms can arise from nonliving matter. This theory was widely accepted in the past, as people observed the apparent emergence of organisms from decaying matter or stagnant water. However, this belief was later disproven by experiments conducted by Louis Pasteur and others, which demonstrated that living organisms only arise from preexisting living organisms through processes such as reproduction or germination.

Submit
18. When humans manipulate the genes of microorganisms the process is called

Explanation

Genetic engineering refers to the process of manipulating the genes of microorganisms, plants, or animals to produce desired traits or characteristics. This can involve inserting, deleting, or modifying specific genes to enhance their functions or create new ones. Bioremediation, on the other hand, is the use of microorganisms to clean up pollutants in the environment. Epidemiology is the study of diseases and their patterns, while immunology focuses on the immune system and its response to diseases. Therefore, genetic engineering is the correct answer as it specifically relates to the manipulation of genes in microorganisms.

Submit
19. The most immediate result of destruction of a cell's ribosomes would be 

Explanation

If a cell's ribosomes are destroyed, the most immediate result would be that protein synthesis would stop. Ribosomes are responsible for translating the genetic information from DNA into proteins, so without functioning ribosomes, the cell would not be able to produce proteins.

Submit
20. Endospores are 

Explanation

Endospores are a unique form of bacterial survival structures that are metabolically inactive, meaning they are not actively carrying out any metabolic processes. They are also highly resistant to heat, chemical destruction, and radiation. This allows them to withstand harsh environmental conditions such as extreme temperatures, exposure to chemicals, and high levels of radiation. Therefore, the correct answer is that all of the choices are correct.

Submit
21. Which of the following is present in gram positive and gram negative cell wall

Explanation

Peptidoglycan is present in both gram positive and gram negative cell walls. It is a polymer made up of sugars and amino acids that provides structural support to the cell wall. Gram positive bacteria have a thick layer of peptidoglycan, while gram negative bacteria have a thinner layer surrounded by an outer membrane. Teichoic acid is only present in gram positive cell walls, and lipopolysaccharides are only present in gram negative cell walls. Therefore, the correct answer is peptidoglycan.

Submit
22. The function of bacterial endospores is

Explanation

Bacterial endospores serve the purpose of protecting the genetic material during harsh conditions. This is achieved by forming a tough outer layer that shields the DNA and other essential components from extreme temperatures, radiation, desiccation, and harmful chemicals. The endospores allow the bacteria to remain dormant and survive in unfavorable environments until conditions become favorable again for growth and reproduction.

Submit
23. A microbiologist makes a fixed smear of bacterial cells and stains them with methylene blue. all the cells appear blue under the oil lens. this is an example of 

Explanation

In this scenario, the microbiologist made a fixed smear of bacterial cells and stained them with methylene blue. The fact that all the cells appear blue under the oil lens suggests that the stain is uniformly coloring the cells, without any contrast or differentiation. This indicates that the staining technique used is simple staining, where a single dye is used to color all the cells in a sample.

Submit
24. Using microbes to break down and remove toxic wastes in water and soil is called

Explanation

Bioremediation is the process of using microorganisms to break down and remove toxic wastes in water and soil. This technique takes advantage of the natural ability of certain microbes to degrade or transform harmful substances into less toxic forms. By introducing these beneficial microbes into contaminated areas, bioremediation can help restore the environmental balance and reduce the harmful effects of pollutants.

Submit
25. If microbiologist is studying a specimen at a total mag of 950x, what is the magnifying power of the objective lens if the ocular lens is 10x

Explanation

The magnifying power of a microscope is determined by multiplying the magnification of the objective lens by the magnification of the ocular lens. In this case, the ocular lens has a magnification of 10x. Since the total magnification is given as 950x, we can divide 950 by 10 to find the magnification of the objective lens. This gives us a magnifying power of 95x for the objective lens.

Submit
26. This bacterium has a life cycle that includes elementary and reticulate bodies

Explanation

Chlamydia is the correct answer because it is a bacterium that has a unique life cycle involving two distinct forms: elementary bodies and reticulate bodies. The elementary bodies are the infectious form that can survive outside the host, while the reticulate bodies are the replicative form that multiply within host cells. This life cycle allows Chlamydia to successfully infect and reproduce in various host organisms, causing a range of diseases such as sexually transmitted infections and respiratory tract infections.

Submit
27. Positive stain use two or more stains it is referred to as _____ stain

Explanation

When a positive stain uses two or more stains, it is referred to as a differential stain. Differential stains are used to differentiate between different types of microorganisms or different parts of a microorganism. This staining technique allows for the visualization and distinction of specific structures or components within the microorganisms, helping in their identification and classification.

Submit
28. Gram stain, acid-fast stain, and endospore stain 

Explanation

Gram stain, acid-fast stain, and endospore stain are all examples of differential stains. Differential stains are used to distinguish between different types of cells or cell structures based on their physical or chemical properties. In this case, these stains are used to differentiate between different cell wall structures. The staining process involves using heat to force the dye into the cell structures, allowing for better visualization and differentiation.

Submit
29. A prokaryotic cell wall that is primarily peptidoglycan with small amounts of teichoic acid and lipoteichoic acid is

Explanation

A prokaryotic cell wall that is primarily composed of peptidoglycan with small amounts of teichoic acid and lipoteichoic acid is classified as gram-positive. Gram-positive bacteria have a thick layer of peptidoglycan in their cell walls, which retains the crystal violet stain during the Gram staining process, causing them to appear purple under a microscope. Teichoic acid and lipoteichoic acid are unique components found in the cell walls of gram-positive bacteria, further supporting this classification. Gram-negative bacteria, on the other hand, have a thinner layer of peptidoglycan and an outer membrane, which makes them appear pink after the Gram staining process. Archaea have a different cell wall composition and structure compared to bacteria, and spheroplasts are bacterial cells that have had their cell walls partially or completely removed.

Submit
30. Organisms called parasites are 

Explanation

Parasites are organisms that live in or on another organism (host) and obtain nutrients from the host, often causing harm in the process. They rely on the host for survival and reproduction, which can lead to negative effects on the host's health and well-being. Therefore, parasites may be harmful to their host.

Submit
31. Which microscope achieves the greatest resolution and highest magnification

Explanation

The electron microscope achieves the greatest resolution and highest magnification among the options given. Unlike light microscopes, which use visible light to magnify and resolve images, electron microscopes use a beam of electrons. Electrons have a much shorter wavelength than visible light, allowing for higher resolution and greater magnification. This enables electron microscopes to visualize extremely small structures and details that would be impossible to see with other types of microscopes.

Submit
32. Enzymes are 

Explanation

Enzymes are proteins and some are RNA that function as catalysts. Proteins and RNA can both act as enzymes, facilitating and speeding up chemical reactions. Enzymes work by lowering the activation energy required for a reaction to occur, thereby increasing the rate of the reaction. They are not used up in the reactions they catalyze and can be reused multiple times. Therefore, the correct answer is that enzymes can be proteins and some are RNA that function as catalysts.

Submit
33. The majority of reduced NAD/NADH is produced in

Explanation

The Krebs cycle, also known as the citric acid cycle, is a series of chemical reactions that occur in the mitochondria of cells. This cycle is an essential part of cellular respiration, which is the process by which cells convert glucose into energy. During the Krebs cycle, reduced NADH is produced through the oxidation of glucose and other molecules. This reduced NADH carries high-energy electrons that are used in the electron transport chain (ETC) to generate ATP, the main energy currency of the cell. Therefore, the majority of reduced NAD/NADH is produced in the Krebs cycle.

Submit
34. The transfer of genes during bacterial conjugation involve rigid, tubular appendages called

Explanation

Bacterial conjugation is a process where genetic material is transferred between bacterial cells through direct contact. During this process, the transfer of genes is facilitated by the presence of rigid, tubular appendages called sex pili. These sex pili help in establishing physical contact between the donor and recipient bacterial cells, allowing for the transfer of genetic material. Flagella are whip-like structures used for bacterial movement, cilia are short hair-like structures used for movement or sensing, and fimbriae are short, hair-like appendages used for attachment to surfaces. None of these structures are directly involved in the transfer of genes during bacterial conjugation.

Submit
35. The term that refers to the presence of flagella all over the cell surface is 

Explanation

Peritrichous refers to the presence of flagella all over the cell surface. This means that the flagella are distributed evenly around the cell, allowing it to move in any direction. Amphitrichous refers to the presence of flagella at both ends of the cell, atrichous refers to the absence of flagella, and monotrichous refers to the presence of a single flagellum. Therefore, peritrichous is the correct term to describe the presence of flagella all over the cell surface.

Submit
36. This bacterium is a member parasite that adheres to and damages the mucous membrane of the respiratory, urinary, and reproductuve tracts

Explanation

Mycoplasma is a bacterium that is known to be a member parasite, as it adheres to and causes damage to the mucous membranes of various tracts in the body, including the respiratory, urinary, and reproductive tracts. This bacterium lacks a cell wall, which allows it to attach to and invade the host's cells, leading to infection and subsequent damage. Mycoplasma infections can result in a range of symptoms depending on the affected tract, including respiratory issues, urinary tract infections, and reproductive problems.

Submit
37. Which of the following IS NOT an example of biofilm

Explanation

The correct answer is "single bacterial cell growing on an agar surface." This is because biofilms are communities of microorganisms that adhere to surfaces and form a protective matrix. In contrast, a single bacterial cell growing on an agar surface does not form a biofilm as it does not involve the formation of a community or a protective matrix.

Submit
38. CO2 IS 

Explanation

The correct answer is "all of the above". This means that CO2 is removed from the atmosphere during photosynthesis, it is a source of carbon, it is returned to the atmosphere during respiration and fermentation, and it is used by marine organisms to make limestone for their hard shells.

Submit
39. Identification of bacteria require a study of all but which of the following

Explanation

To identify bacteria, a study of their microscopic and macroscopic morphology is necessary to observe their physical characteristics. Bacterial physiology helps understand their metabolic processes and behavior. Serological analysis involves studying the antibodies produced in response to bacterial antigens. However, quantitative analysis refers to the measurement and analysis of quantities or amounts, which may not be directly relevant to identifying bacteria. Therefore, it is not required for the identification process.

Submit
40. All of the following are correct about slime layer, except

Explanation

The slime layer is a type of glycocalyx that surrounds the cell and protects it from the loss of water and nutrients. It forms a sticky layer that can be difficult to wash off the cell. However, it does not play a role in cell motility.

Submit
41. Oxidation of ammonia (NH4+) to nitrate (NO3-) is called

Explanation

Nitrification is the correct answer because it is the process by which ammonia (NH4+) is oxidized to nitrate (NO3-). This process is carried out by two types of bacteria: ammonia-oxidizing bacteria that convert ammonia to nitrite (NO2-) and nitrite-oxidizing bacteria that convert nitrite to nitrate. Nitrification is an important step in the nitrogen cycle, as it converts ammonia, which is toxic to many organisms, into a less toxic form that can be utilized by plants for growth. Ammonification, nitrogen fixation, and photosynthesis are not related to the oxidation of ammonia to nitrate.

Submit
42. Which scientist discovered heat resistant bacterial spores

Explanation

Ferdinand Cohn is credited with discovering heat resistant bacterial spores. He was a German biologist and botanist who made significant contributions to the field of microbiology. Cohn conducted extensive research on bacteria and was the first to describe and classify bacterial endospores, which are highly resistant to heat and other adverse conditions. His work on spore formation and resistance laid the foundation for understanding the survival mechanisms of bacteria and their ability to withstand extreme environments.

Submit
43. The rash and/or hemorrhage associated to Rocky Mountain spotted fever and Typhus occur when this bacterium targets the endotheilal cells that line blood vessels

Explanation

Rickettsia is a bacterium that causes diseases such as Rocky Mountain spotted fever and Typhus. These diseases are characterized by a rash and/or hemorrhage. The explanation for the correct answer is that Rickettsia specifically targets the endothelial cells that line the blood vessels. This leads to damage and inflammation of the blood vessels, resulting in the symptoms observed in patients with these diseases.

Submit
44. What does a positive stain color

Explanation

not-available-via-ai

Submit
45. Glycocalyx is

Explanation

The correct answer is capsule. The glycocalyx is a layer of polysaccharides that surrounds the cell wall of some bacteria. It can exist in two forms: capsule and slime layer. The capsule is a well-organized and tightly bound layer that helps protect the bacteria from the host's immune system and allows them to adhere to surfaces. It also helps in the formation of biofilms. Pili are hair-like structures that help in bacterial attachment and conjugation. The outer membrane is a unique feature of gram-negative bacteria. The cell wall provides structural support and protection to the bacterial cell.

Submit
46. The conversion of gaseous nitrogen (N2) to ammonium (NH4+) occurs during

Explanation

Nitrogen fixation is the process in which gaseous nitrogen (N2) is converted into ammonium (NH4+). This process is carried out by certain bacteria, either free-living or symbiotic, which have the ability to convert atmospheric nitrogen into a form that can be used by plants and other organisms. Ammonification, on the other hand, is the process of converting organic nitrogen into ammonium, while nitrification is the process of converting ammonium into nitrate (NO3-). Photosynthesis is the process by which plants convert sunlight into energy, and it does not involve the conversion of nitrogen. Therefore, the correct answer is nitrogen fixation.

Submit
47. Type of microscope in which you would see bright illuminated specimens against a black background is

Explanation

In a dark field microscope, the specimens appear bright and illuminated against a black background. This is achieved by using a special condenser that blocks direct light from reaching the objective lens. Instead, only light that is scattered or refracted by the specimen enters the objective lens, creating a contrasting image. This technique is particularly useful for observing transparent or unstained specimens, as it enhances their visibility and allows for better examination of their fine details.

Submit
48. An apoenzyme

Explanation

An apoenzyme refers to the protein component of a holoenzyme. A holoenzyme is an active enzyme that consists of both a protein component (apoenzyme) and a non-protein component (coenzyme or prosthetic group). The apoenzyme alone is inactive and requires the binding of the coenzyme or prosthetic group to become functional. Therefore, the correct answer is that an apoenzyme is the protein part of a holoenzyme.

Submit
49. Bacterial endospores function in

Explanation

Bacterial endospores function in survival. Endospores are a dormant and highly resistant form of bacteria that can withstand harsh environmental conditions such as extreme temperatures, lack of nutrients, and exposure to chemicals or radiation. By forming endospores, bacteria can protect their genetic material and survive unfavorable conditions until more favorable conditions arise. This ability to enter a dormant state and then revive when conditions are suitable is crucial for the long-term survival of bacteria.

Submit
50. Which of the following is INCORRECT regarding bacterial cell wall?

Explanation

The bacterial cell wall is not composed of a repeating framework of lipids. Instead, it is primarily composed of peptidoglycan, a polymer made up of repeating units of sugars and amino acids. The peptidoglycan provides strength and rigidity to the cell wall, which helps determine the shape of the bacterium and prevents it from bursting due to changes in osmotic pressure. The cell wall is also a target for certain antibiotics, which disrupt its synthesis and weaken the bacterium.

Submit
51. Which microscope bombard a whole, metal-coated specimen with electrons moving back and forth over it

Explanation

A scanning electron microscope (SEM) bombards a whole, metal-coated specimen with electrons moving back and forth over it. SEMs use a focused beam of electrons to scan the surface of a sample, creating detailed images of the specimen's surface morphology. The electrons interact with the atoms in the sample, producing signals that can be detected and used to create an image. This technique is particularly useful for studying the surface features of materials and provides high-resolution images with great depth of field.

Submit
52. Which term is not used to describe bacterial cell shape

Explanation

The term "tetrad" is not used to describe bacterial cell shape. A tetrad refers to a group of four cells that are formed by the division of a single bacterial cell in a specific pattern. It is not a specific shape of a bacterial cell, but rather a specific arrangement of cells. The other terms, coccus, vibrio, and rod, are all used to describe different shapes of bacterial cells.

Submit
53. Metabollic pathways that regenerate their starting point is called _____ pathways.

Explanation

Cyclic pathways are metabolic pathways that regenerate their starting point. In these pathways, the initial substrate is converted into intermediate products, which are then further metabolized to regenerate the starting substrate. This creates a circular flow of metabolites within the pathway. Unlike linear pathways, where the end product is different from the starting substrate, cyclic pathways maintain the same starting point throughout the process. Bi-directional pathways allow for reversible reactions, but they do not necessarily regenerate the starting point. Convergent pathways involve multiple substrates converging into a common intermediate, but they do not necessarily regenerate the starting point.

Submit
54. What chemical causes death in many eukaryotes because it blocks cytochrome c oxidase?

Explanation

Cyanide is a chemical that blocks cytochrome c oxidase, an enzyme involved in cellular respiration. This enzyme is responsible for the final step in the electron transport chain, which generates ATP, the energy currency of the cell. By blocking cytochrome c oxidase, cyanide prevents the production of ATP, leading to cellular dysfunction and ultimately death. This effect is observed in many eukaryotes, including humans, making cyanide a potent and lethal poison.

Submit
55. Magnification is achieved in a compound microscope through the initial magnification of the specimen by the ______ lens. This image is then projected to the _________ lens that will further magnify the specimen to form a virtual image received by the eye

Explanation

In a compound microscope, magnification is achieved through two lenses: the objective lens and the ocular lens. The objective lens initially magnifies the specimen, creating an image. This image is then projected to the ocular lens, which further magnifies the specimen to form a virtual image that is received by the eye. Therefore, the correct answer is objective for the first lens and ocular for the second lens.

Submit
56. All of the following are correct about prokaryotes, except

Explanation

Prokaryotes are single-celled organisms that lack a nucleus and membrane-bound organelles. They are generally smaller and less complex than eukaryotes. However, prokaryotes do not have organelles. Organelles are specialized structures within a cell that perform specific functions, such as mitochondria or chloroplasts in eukaryotic cells. Prokaryotes, on the other hand, have simpler internal structures and lack these membrane-bound organelles.

Submit
57. They contain pigment bacteriochlorophyll and do not give off oxygen as a product of photosynthesis

Explanation

Purple sulfur bacteria are a type of bacteria that contain pigment bacteriochlorophyll and do not produce oxygen as a byproduct of photosynthesis. These bacteria use a process called anoxygenic photosynthesis, where they utilize light energy to convert inorganic compounds such as hydrogen sulfide into organic compounds. Unlike plants and some other bacteria, purple sulfur bacteria do not release oxygen during this process.

Submit
58. Enzymes that are only produced when substrate is present are termed

Explanation

Induced enzymes are produced only when their specific substrate is present. These enzymes are not continuously produced by the organism but are synthesized in response to the presence of the substrate. This allows the organism to conserve energy by only producing enzymes when they are needed. Therefore, the correct answer is "induced enzyme".

Submit
59. Basic dyes are

Explanation

Basic dyes are attracted to the acidic substances of bacterial cells because they have a positive charge. Bacterial cells typically have negatively charged components, such as nucleic acids and certain proteins. The attraction between the positive charge of the basic dye and the negative charge of the bacterial cell components allows the dye to bind to the cell, resulting in staining. This property of basic dyes makes them suitable for negative staining techniques, where the background is stained while the cells remain unstained.

Submit
60. What is the key differentiating step in gram stain procedure?

Explanation

The key differentiating step in the gram stain procedure is the decolorization step. This step involves the application of a decolorizing agent, usually alcohol or acetone, which removes the primary stain from certain types of bacteria. This allows for differentiation between gram-positive and gram-negative bacteria. Gram-positive bacteria retain the primary stain and appear purple, while gram-negative bacteria lose the primary stain and are then counterstained with a contrasting color, usually pink or red. The decolorization step is crucial in determining the gram reaction of bacteria and plays a significant role in the identification and classification of bacterial species.

Submit
61. Spirochetes have a twisting and flexing locomotion due to 

Explanation

Periplasmic flagella allow spirochetes to have a twisting and flexing locomotion. Unlike external flagella or cilia, periplasmic flagella are located within the periplasmic space, which is between the cell membrane and the outer membrane of spirochetes. This unique arrangement enables spirochetes to move in a corkscrew-like motion, propelling themselves forward and allowing them to navigate through various environments. The presence of periplasmic flagella is a distinguishing characteristic of spirochetes and contributes to their motility.

Submit
62. Substrate level phosphorylation in

Explanation

Glycolysis is the initial step in cellular respiration where glucose is broken down into pyruvate, producing a small amount of ATP through substrate-level phosphorylation. The pyruvate molecules then enter the Krebs cycle, a series of reactions that occur in the mitochondria. In the Krebs cycle, more ATP is produced through substrate-level phosphorylation, as well as the release of high-energy electrons. These electrons are then transferred to the electron transport chain (ETC), where they combine with oxygen to produce a large amount of ATP through oxidative phosphorylation. Therefore, the correct answer is glycolysis + Krebs cycle, as both processes involve substrate-level phosphorylation.

Submit
63. In bacterial cells, the ETC is located in 

Explanation

In bacterial cells, the electron transport chain (ETC) is located in the cell membrane. The cell membrane of bacteria serves as the site for various metabolic processes, including the ETC. The ETC is responsible for the transfer of electrons and the generation of a proton gradient, which is used to produce ATP. The location of the ETC in the cell membrane allows for efficient electron transfer and ATP synthesis. Unlike eukaryotic cells, bacteria lack mitochondria and chloroplasts, which are the organelles where the ETC is located in eukaryotic cells. Ribosomes, on the other hand, are responsible for protein synthesis and are not directly involved in the ETC.

Submit
64. Which of the following is mismatched

Explanation

The correct answer is b.burgdoferi: syphilis. This is a mismatch because b.burgdoferi is the bacterium that causes Lyme disease, not syphilis. Syphilis is caused by the bacterium Treponema pallidum.

Submit
65. The specimen preparation that is best for viewing cell motility is

Explanation

The hanging drop method is the best specimen preparation for viewing cell motility because it allows for the observation of live, moving cells. In this technique, a drop of the specimen is placed on a coverslip, which is then inverted and suspended over a depression slide. The hanging drop creates a moist environment that keeps the cells alive and allows them to move freely. This method provides a clear and dynamic view of cell motility, making it ideal for studying the movement and behavior of cells.

Submit
66. Which of the following prokaryotes lack cell wall

Explanation

Mycoplasmas lack a cell wall. Unlike other prokaryotes, they do not have a rigid cell wall made of peptidoglycan. Instead, they have a flexible cell membrane that gives them a unique shape and allows them to change their size and shape. This lack of a cell wall makes them resistant to certain antibiotics that target cell wall synthesis. Mycoplasmas are known for their small size and ability to cause various infections in humans and animals.

Submit
67. Important components of coenzymes are

Explanation

Coenzymes are organic molecules that work alongside enzymes to facilitate various biochemical reactions in the body. They are derived from vitamins, which are essential nutrients that the body needs in small amounts for proper functioning. Vitamins are important components of coenzymes because they provide the necessary chemical groups or functional units that are required for the coenzymes to carry out their specific roles in enzymatic reactions. Metallic ions, active sites, and substrates are also important in enzymatic reactions, but they are not the primary components of coenzymes.

Submit
68. Each of the following are true of enzymes except

Explanation

Enzymes are biological catalysts that speed up chemical reactions in living organisms. They achieve this by lowering the activation energy required for a reaction to occur. Therefore, the statement "they increase the activation energy of a reaction" is incorrect. Enzymes actually decrease the activation energy, making it easier for the reaction to proceed. This allows reactions to occur more quickly and efficiently in the body.

Submit
69. Acid-fast stain is used to identify organisms containing what chemical in their cell wall?

Explanation

The correct answer is mycolic acid. Acid-fast stain is a special staining technique used to identify organisms that have mycolic acid in their cell walls. Mycolic acid is a unique lipid found in the cell walls of certain bacteria, particularly those of the genus Mycobacterium, which includes the bacteria that cause tuberculosis and leprosy. The acid-fast stain helps to differentiate these bacteria from others by staining them a bright red color, while other bacteria are stained blue. This staining technique is important for the diagnosis and identification of these specific bacteria.

Submit
70. Glycolysis 

Explanation

Glycolysis is the metabolic pathway that breaks down glucose into pyruvate. It occurs in the cytoplasm of cells and is the first step in both aerobic and anaerobic respiration. During glycolysis, 2 ATP molecules are used to initiate the process. However, it produces 4 ATP molecules through substrate-level phosphorylation, resulting in a net gain of 2 ATP molecules. In the absence of oxygen, glycolysis can still occur, but the end product, pyruvate, is converted into either lactate or ethanol, depending on the organism. Therefore, the correct answer is "uses 2 ATP, produces 4 ATP, without oxygen."

Submit
71. All of the following are exoenzymes except

Explanation

ATP synthase is not an exoenzyme because it is not secreted outside of the cell. Exoenzymes are enzymes that are produced and released by cells to act on substrates outside of the cell. Streptokinase, penicillinase, and collagenase are all examples of exoenzymes as they are secreted by cells to act on substrates outside of the cell.

Submit
72. Chemical analysis of bacterial cell structure detects calcium dipicolinic acid. What is the identity of this structure?

Explanation

The presence of calcium dipicolinic acid is a characteristic feature of endospores. Endospores are specialized structures produced by certain bacteria as a means of survival in harsh conditions. They are highly resistant to heat, radiation, and chemicals. The calcium dipicolinic acid helps in stabilizing the DNA within the endospore, protecting it from damage. Therefore, the identity of the structure being described in the question is an endospore.

Submit
View My Results

Quiz Review Timeline (Updated): Mar 21, 2023 +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

  • Current Version
  • Mar 21, 2023
    Quiz Edited by
    ProProfs Editorial Team
  • Jun 07, 2016
    Quiz Created by
    Tammychoe
Cancel
  • All
    All (72)
  • Unanswered
    Unanswered ()
  • Answered
    Answered ()
Disease-causing microorganisms are called
The microorganisms that recycle nutrients by breaking down dead matter...
The microorganisms that do not have a nucleus in their cell wall are...
The Dutch merchant who made and used quality magnifying lenses to see...
Koch's postulates are criteria used to establish that 
The outcome of the gram stain is based on differences in...
The fossil record has est. that prokaryotes existed on earth for...
Which activity is an example of biotechnology?
Microorganisms are best defined as organisms that 
These bacteria are small gram neg, obligate intracellular parasites...
The primary purpose of staining cells on a microscope slide is to
_____ organelles in algae and plants are known to have evolved from...
What is the correct sequence for gram stain?
Why is immersion oil often used when viewing specimens under the...
This bacterium causes a commonly acquired sexually transmitted...
Which bacterium was the first organisms to produce oxygen as a...
Spontaneous generation is the belief that
When humans manipulate the genes of microorganisms the process is...
The most immediate result of destruction of a cell's ribosomes...
Endospores are 
Which of the following is present in gram positive and gram negative...
The function of bacterial endospores is
A microbiologist makes a fixed smear of bacterial cells and stains...
Using microbes to break down and remove toxic wastes in water and soil...
If microbiologist is studying a specimen at a total mag of 950x, what...
This bacterium has a life cycle that includes elementary and...
Positive stain use two or more stains it is referred to as _____ stain
Gram stain, acid-fast stain, and endospore stain 
A prokaryotic cell wall that is primarily peptidoglycan with small...
Organisms called parasites are 
Which microscope achieves the greatest resolution and highest...
Enzymes are 
The majority of reduced NAD/NADH is produced in
The transfer of genes during bacterial conjugation involve rigid,...
The term that refers to the presence of flagella all over the cell...
This bacterium is a member parasite that adheres to and damages the...
Which of the following IS NOT an example of biofilm
CO2 IS 
Identification of bacteria require a study of all but which of the...
All of the following are correct about slime layer, except
Oxidation of ammonia (NH4+) to nitrate (NO3-) is called
Which scientist discovered heat resistant bacterial spores
The rash and/or hemorrhage associated to Rocky Mountain spotted fever...
What does a positive stain color
Glycocalyx is
The conversion of gaseous nitrogen (N2) to ammonium (NH4+) occurs...
Type of microscope in which you would see bright illuminated specimens...
An apoenzyme
Bacterial endospores function in
Which of the following is INCORRECT regarding bacterial cell wall?
Which microscope bombard a whole, metal-coated specimen with electrons...
Which term is not used to describe bacterial cell shape
Metabollic pathways that regenerate their starting point is called...
What chemical causes death in many eukaryotes because it blocks...
Magnification is achieved in a compound microscope through the initial...
All of the following are correct about prokaryotes, except
They contain pigment bacteriochlorophyll and do not give off oxygen as...
Enzymes that are only produced when substrate is present are termed
Basic dyes are
What is the key differentiating step in gram stain procedure?
Spirochetes have a twisting and flexing locomotion due to 
Substrate level phosphorylation in
In bacterial cells, the ETC is located in 
Which of the following is mismatched
The specimen preparation that is best for viewing cell motility is
Which of the following prokaryotes lack cell wall
Important components of coenzymes are
Each of the following are true of enzymes except
Acid-fast stain is used to identify organisms containing what chemical...
Glycolysis 
All of the following are exoenzymes except
Chemical analysis of bacterial cell structure detects calcium...
Alert!

Advertisement