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Example Questions
Example Question #72 : Microbiology
Prokaryotes that can utilize oxygen if available, but do not require it, are called __________.
constitutive aerobes
obligate aerobes
constitutive anaerobes
facultative anaerobes
obligate anaerobes
facultative anaerobes
Facultative anaerobes are adaptive prokaryotes that can survive in either aerobic or anaerobic environments. These organisms are capable of both cellular respiration, through use of the electron transport chain along the cell membrane, and fermentation. They will adopt the more efficient process (cellular respiration) when oxygen is present, but can easily switch between one metabolism and the other.
Obligate anaerobes cannot produce energy in the presence of oxygen, and obligate aerobes cannot produce energy in the absence of oxygen.
Example Question #75 : Microbiology
All of the following are true about bacilli bacteria except:
I. All bacilli are rod-shaped
II. All bacilli are gram positive
III. All bacilli are aerobic
II and III
II only
I and III
III only
II and III
Bacilli is a genus of bacteria that are characterized by their rod-shaped cells. Bacilli can be either gram positive, such as Bacillus anthracis, or gram negative, such as Salmonella enterica. Bacilli bacteria can be either aerobic (require oxygen) or facultative anaerobes (can thrive in both oxygen rich and oxygen poor environment). Bacilli are not exclusively aerobic, nor are they exclusively gram positive.
Example Question #1 : Fungi
A fungus that always reproduces asexually is most likely classified as __________.
Basidomycetes
Zygomycetes
Deuteromycetes
Asomycetes
Microsporidia
Deuteromycetes
Fungi are typically characterized based on reproductive methods and structures. All fungi can reproduce asexaully, but only deuteromycetes lack a sexual reproduction phase, only reproducing asexually.
Example Question #1012 : Biology
What characteristic do both all plants and fungi have in common?
Both use chitin primarily in their cell walls
They have nothing in common
Both use spores to propagate
Both use photosynthesis for energy production
Both consist of eukaryotic cells
Both consist of eukaryotic cells
Both plants and fungi consist of eukaryotic cells. Their cells contain membrane-enclosed nuclei and organelles which is a defining characteristic of eukaryotic cells.
Fungi do not photosynthesize. While seedless plants and fungi use spores, this trait is not common to all plants. Plant cell walls are composed of collagen, while fungi use chitin.
Example Question #1013 : Biology
An antifungal cream advertises to chemically attack the fungal cells without harming the skin. The antifungal chemical most likely acts on which of the following?
Eukaryotic membranes
There is not enough information provided
Mitochondria
The nucleus
Chitin
Chitin
The antifungal compound is likely specific to chitin, as it is a common material of many fungi cell wall structures. Chitin is resistant to breakdown, and is actually found in insect exoskeletons. The incorrect answers are found in skin cells as well as fungal cells, and would harm the skin if the chemical attacked these structures.
Example Question #1 : Fungi
A scientist is interested in genetically engineering a fungus that has a limited reproductive process so that it does not accidentally cross breed with other fungi in the laboratory. Which process should be disrupted to hinder fungal reproduction?
None of these
Septa formation
Spore formation
Mycelium formation
Nutrient absorption
Spore formation
Most fungi reproduce by creating microscopic spores, which are reproductive cells than can be dispersed by wind, water, or animals. Spores can be generated sexually or asexually. If the scientist disrupts spore formation, the fungus will not be able to spread spores to other areas of the laboratory.
Inhibition of spore formation would limit the fungus's ability to reproduce over distance, however fungi have multiple methods of reproduction and would still be able to generate progeny even if spore production is disabled.
Example Question #1015 : Biology
Fungal hyphae form a mesh of tissue that infiltrates food sources and absorbs nutrients. This tissue structure is called __________.
None of these
Fungal roots
Mycelium
Gametangia
Zygospores
Mycelium
Congregation of hyphae form mycelium, the tissue that allows fungi to absorb nutrients from surrounding food sources. Often, the majority of mycelium mass is not visible to the observer. "Fungal roots" is a misleading answer, even though mycelium looks similar to root structures of plants. Gametangia is where gametes are produced in the fungus.
Example Question #81 : Microbiology
Fungi can reproduce in all of the following manners except __________.
by binary fission
by sexual spores
by axsexual spores
vegetatively
by binary fission
Binary fission occurs in prokaryotes and is a form of asexual reproduction. Fungi are considered haploid eukaryotes and undergo reproduction through processes like asexual spore release, vegetative reproduction, and sexual spore release. Asexual spores do not have DNA mixing, while sexual spores do have DNA mixing. Vegetative reproduction is when part of the fungus breaks off and forms a new fungus.
Example Question #82 : Microbiology
The life cycle of most fungi is best described by which of the following statements?
Fungi only reproduce asexually
Fungi have both sexual and asexual portions of their life cycle
Fungi only reproduce sexually
None of these
Fungi are unique and have different mechanisms of reproduction
Fungi have both sexual and asexual portions of their life cycle
Most fungi have a life cycle that consists of both sexual and asexual periods. Spores can be produced sexually or asexually, depending on the availability of male or female gametes. This has provided an advantage to fungi to be able to spread and propagate in a variety of environments.
Example Question #81 : Microbiology
Which of the following types of microscopy is best for the visualization of living organisms?
Electron microscope
Compound light microscope
Phase contrast microscope
Scanning electron microscope
Light microscope
Phase contrast microscope
A phase contrast microscope is best for the visualization of living things because the other types of microscopy require methods of mounting onto a slide that can kill the organisms.
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