BIOL 260 STAGE 01 EXAM
The cellulose that makes up the plant cell walls of grass can be digested by certain species of...
Microbes
Why do microorganisms serve as important models for study of higher organisms?
Microorganisms have the same fundamental metabolic and genetic properties as other organisms
In the 1700s, Lazzaro Spallanzani boiled and sealed flasks of broth and then looked for growth. Based on the results of his experiments, he concluded that...
Microorganisms in air could enter open flasks
In research, bacteria often serve as __________________________, meaning that they are studied as a means to better understand processes fundamental to higher life forms
Model organisms
Compared to the diversity of plants and animals, microbes as a group are...
More diverse
What is normal microbiota?
Organisms that populate the human body and which protect it from disease
Which disease is less common due to rat control, precautions taken with infected patients, and antibiotic treatment?
Plague
What is a paralysis-inducing disease that has been nearly eliminated due to vaccination?
Polio
Which is the most resistant to sterilization techniques?
Prions
Which of the following are composed solely of proteins?
Prions
Which of the following cannot reproduce independently?
Prions, viroids
Lazzaro Spallanzani's experiments in the 1700s showed that flasks of broths that had been boiled for long periods of time and sealed...
Remained sterile
Although archaea and bacteria differ in a number of important characteristics, it was ultimately significant differences in their ________________ that provided the basis for separating the two groups of prokaryotes into different domains
Ribosomal RNA sequences
When an extensive amount of experimental evidence supports a hypothesis, the explanation may become a...
Scientific theory
Algae are...
Single-celled photosynthetic eukaryotes Multicellular photosynthetic eukaryotes
Yeast
Single-felled fungus
The species name of Escherichia coli and Escherichia vulneris reflect the...
Site where the organism may be found
The Golden Age of Microbiology occurred soon after...
Spontaneous generation was disproved, and led to a time when the field of microbiology blossomed
If cattle, sheep, and deer had a microbe-free digestive tract, they would...
Starve
To indicate slight differences, members of the same species may be given special __________ designations
Strain
The human body and its microbial inhabitants can be best compared to _______________
The earth's environments and their interacting inhabitants
The human intestinal microbiome allows the body to extract more energy from foods. One reason for this is that...
The human genome encodes relatively few enzymes that degrade complex carbohydrates
The genus name Escherichia originates from...
The name of a scientist
A patient living in Seattle is diagnosed with malaria. What is the most likely explanation for this diagnosis?
The patient was infected while visiting a country where malaria is endemic
Bacteremia
The presence of bacteria in the bloodstream
Viremia
The presence of free viral particles in the blood
Toxemia
The presence of toxins circulating in the bloodstream
When oral antibiotics inhibit the Lactobacillus species that normally predominates in the vagina of mature females, what occurs?
The yeast Candida albicans is allowed to multiply unchecked, resulting in a fungal infection of the area
What feature is unique to bacteria?
Their cell walls contain peptidoglycan
Solid, repeatable, extensive amounts of scientific evidence leads to...
Theory
Which of the following describes how fungi gain energy?
They degrade organic materials with enzymes
Why were Louis Pasteur's experiments with swan-necked flasks so important in helping disprove the theory of spontaneous generation?
They ended arguments that a "vital force" was necessary for spontaneous generation, while preventing contamination from microbes in the air
What is direct damage caused by microorganisms?
Toxins
Virulence factors
Traits of a microbe that specifically allow it to cause disease
T/F: Even though the best studied archaea inhabit extreme environments, many others are widely distributed in soils, oceans, marshes, and even the intestinal tracts of animals
True
T/F: Without microorganisms, we would run out of certain nutrients
True
T/F: Some scientists could not reproduce the results of Pasteur's swan-necked flask experiment
True - when scientists used hay instead of sugar or yeast to make the broth, growth occurred even after boiling
Resident microbiota
Typically inhabit body sites for extended periods of time
Eukaryotic organisms can be...
Unicellular or multicellular
Which of the following are classified as acellular infectious agents?
Viruses, viroids, prions
Emerging infectious disease
- An infectious disease that has become more common in the last 35 years - Newly recognized or have recently increased in incidence
Which of the following can be infected by viruses?
- Animals - Plants - Fungi - Protists - Bacteria - NOT viroids - NOT prions
Which of the following are produced metabolically by microorganisms?
- Ethanol as biofuel - Antibiotics - Cellulose used in stereo headsets
Examples of signs
- Fever - Rash - Elevated WBC count - Pus formation
A human baby will acquire normal microbiota...
- From ingested food and from the environment - From passage through the birth canal - From contact with other humans - Due to exposure to microbes in the environment
A carrier is an individual who has which characteristics?
- Harbors an infectious agent for a long time after infection, often without signs or symptoms - Is still contagious to individuals around him or her - Exhibits none of the symptoms of the illness
Which of the following describes a viroid?
- It consists of RNA - It can infect plants
Process of publishing in peer-reviewed journals is important because...
- It helps ensure that published results are valid and founded in science - It allows scientists to repeat the experiment to ensure the validity of the findings
Microorganisms are useful in the study of higher life forms for which of the following reasons?
- Microorganisms have the same fundamental genetic properties - Microorganisms have the same basic metabolic mechanisms - Microorganisms multiply quickly - Microorganisms are cheaper to study
Examples of symptoms
- Nausea - Muscle soreness or weakness - Pain
Which of the following are true regarding viruses?
- Outside of host cells, viruses are inactive - Viruses can only multiply within host cells
Infectious diseases can reemerge as a result of...
- Pathogens becoming resistant to antimicrobial medications - Parents refusing to vaccinate their children
Like plants, some microorganisms...
- Produce oxygen (O2) - Are photosynthetic
Characteristics of archaea that are similar to bacteria include their...
- Prokaryotic cell structure - Energy sources used - Methods of multiplication - Shapes
Which is true regarding scientific names?
- Scientific names are italicized or underlined - Genus names are commonly abbreviated - The species name should not be capitalized (only the genus name)
Which of the following are characteristics of protozoa?
- Single-celled eukaryotes - Microscopic - Do NOT possess a rigid cell wall - Are NOT multicellular eukaryotes
Archaea are commonly found in which roles or environments?
- Soils - Oceans - Hot springs - Extremely salty water such as the Great Salt Lake and Dead Sea
Where are algae most likely to be found?
- Surfaces of oceans, lakes, and streams - Moist terrestrial habitats
Which of the following variables may reasonably be assumed to affect the duration of the incubation period?
- The host's general physical condition - The number of infectious particles encountered - Growth rate of the pathogen - NOT the time of year - NOT the gender - NOT the air temperature
The term "microbiome" has which two overlapping meanings?
- The total genetic content of a microbial community - The microbial community itself
Which is true about microorganisms?
- They have killed less people than have been killed in wars - They are not always harmful - We could not survive without them
What are some of the benefits of the normal microbiota to our health?
- They protect us against infection - They produce beneficial compounds - They help us digest our food
Phagocytosis involves multiple steps, each of which is potentially a target for microbes to modify or avoid as a means of evading immune response mechanisms. What is the correct order for the steps involved in phagocytosis of a microbe?
1. Chemotaxis - how does the phagocyte find its way to the microbe(s)? 2. Recognition and attachment - how does the phagocyte know what to gobble up? 3. Engulfment - what does the phagocyte do once it has found its target? 4. Fusion of phagosome with lysosomes
First four steps of the scientific process
1. Make an observation about something and ask a question about the situation 2. Develop an explanation and then devise an experiment to test this explanation 3. Collect data from this experiment 4. Draw a conclusion
Koch's Postulates
1. The microorganism must be present in every case of the disease 2. The organism must be grown in pure culture from diseased hosts 3. The same disease must be produced when a pure culture of the organism is introduced into susceptible hosts 4. The organism must be recovered from the experimentally infected hosts
What is a helminth?
A worm, some of which are parasitic A multicellular parasite such as a roundworm or tapeworm
What is a pathogen?
Any disease-causing microorganism
Members of which domains can be infected by viruses?
Archaea, bacteria, eukarya
Bacteria, such as members of the genus Staphylococcus, belong to the domain ________________
Bacteria
Which organisms lack a membrane-bound nucleus?
Bacteria, archaea
Which of the following are manufactured by microbial fermentation?
Beer, cheese, yogurt (NOT fresh milk + ice cream)
Using microorganisms to degrade toxic chemical spills is an example of _____________________
Biodegradation
Bacteria produce ethanol, hydrogen gas, and certain oils, which all have the potential to be used as...
Biofuels
Which process is the decomposition of harmful pollutants by microbes?
Bioremediation
What is the use of microorganisms to solve practical problems?
Biotechnology
Opportunistic pathogen
Causes disease only when the body's innate or adaptive defenses are compromised / can cause disease in immunocompromised people
All of the following are commonly found in algae...
Cell wall, chloroplasts, flagella, nucleus
Viruses are not microorganisms b/c they are not...
Composed of cells
What is a viroid?
Consists of a single short piece of RNA
Example of direct result of activities of the human host
Consuming different amounts of food. These would be changes in the way a human interacts with the surrounding environment that may alter the normal microbiota composition. - Is this something that human hosts can influence and change directly, if they so choose?
What is a component of a scientific experiment that rules out alternative explanations of the results by showing that the only feature that varied in the experiment was the characteristic being tested?
Control
Some scientists were skeptical of Pasteur's results b/c they...
Could not reproduce his results
John Needham's experiments in the 1700s show that broths that had been boiled and then sealed with a cork...
Could still give rise to microorganisms
Because less than 1% of microorganisms can currently be grown in the lab, most of what we know about the other 99% comes from...
DNA sequencing
Virulence
Degree of pathogenicity of an organism
Which diseases are due to organisms "jumping" from an animal host to using humans as a host?
Emerging
Tyndall's experiments in the 1800s showed that live microorganisms remained in some broths even after they had been boiled for 5 hours. This observation can be explained by the presence of a heat-resistant form of bacteria called an _________________
Endospore
The cells of which group of microorganism contain membrane-bound organelles?
Eukarya
In research, a model organism should...
Function in a manner similar to other organisms
Acute infections are...
Generally short in duration
What is the principle that microorganisms cause certain disease?
Germ Theory of Disease
John Tyndall's experiments in the 1800s showed that microorganisms remained in some broths even after boiling for 5 hours. He later realized that the results of his experiments were due the presence of endospores. Pasteur might have had results similar to Tyndall's if he had used which materials to make his broths?
Hay, soil
Example of physiological variations within the host
Hormonal shifts during pregnancy. These would be changes to the normal homeostatic patterns in the host organism that are not due to the pathogenic infection. - Is this a biochemical change going on inside the host human, most likely without their ability to directly influence the changes?
What are the microscopic filaments of mold?
Hyphae
The _____________ stage of an infectious disease is characterized by the signs and symptoms of that disease
Illness
What is indirect damage caused by microorganisms?
Immune response
Communicable or contagious diseases
Infectious diseases that spread from one host to another
Prions are...
Infectious proteins
Which of the following best describes the cultivation of microorganisms in the lab?
Less than 1% of microorganisms can be cultivated
Spontaneous generation
Life arose from non-living matter
