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85 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Define the following term:
Logistic growth |
Population growth that is controlled by limited resources.
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Define the following term:
Plasmid |
A small, circular section of extra DNA that confers one or more traits to a bacterium and can be reproduced separately from the main bacterial genetic code.
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Define the following term:
Endospore |
The DNA and other essential parts of a bacterium coated with several hard layers
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A bacterium suddenly cannot manufacture proteins.
what component)s) of the cell is (are) not working? |
Since the ribosomes are where proteins are manufactured in the cell, they must not working.
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If a bacterium is anaerobic, would you expect to find it floating at the top of a lake or deep in the muck at the bottom of the lake?
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You would expect to find it deep in the muck, because there is little or no oxygen down there.
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A bacterium is photosynthetic. Is it a decomposer?
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It is not a decomposer, because photosynthetic bacteria are autotrophs.
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A bacterium receives a new trait that it did not previously have. However, it did not participate in conjugation. How is this possible?
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It participated in transformation/transduction , one of the other means by which bacteria get new traits.
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If a sample of food is dehydrate, what condition for bacterial growth are you removing from the food?
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Moisture
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If a population of bacteria is in steady state, does that mean no bacteria are dying?
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A steady stage does not mean that no bacteria are dying. In a steady state, the population does not change because bacteria are reproducing as quickly as others are dying.
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What shape is a bacterium from the genus Streptobacillus?
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Since the name ends in bacillus, it is rod-shaped. You could also say bacillus.
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A population is composed of bacteria that are very sensitive to light. They live in a lake that is in a cave, so they flourish. Slowly, however, a hole begins to erode in the cave's roof. As the days pass, light begins to filter in and the cave starts to be dimly lit. The bacteria begin to die. While the erosion is taking place, however, two individual bacgteria in the soil above ground fall into the lake. These baceria cannot survive in the dimness of the poorly-lit cave, so they die immediately. Days later, the hole has opened up so that light floods the cavern. Nevertheless, the bacteria that were once dying are flourishing, with a population larger than they had before the erosion. Explain how this could have happened.
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A bacterium must have participated in transformation so that the ability to live in light was absorbed from one or both of the dead bacteria that fell into the lake. Then, because there are so many baceria present, that bacterium must have participated in conjugation with several others.
(in other words: The bacterium then started asexually reproducing to rebuild the population. |
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A bacterium is Gram negative and needs light to survive. It lives in a habitat that is completely oxygen-free. To what phylum and class does it belong?
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Gram negative bacteria are in phylum Gracilicutes.
Anaerobic bacteria in this phylum are in class Anoxyphotobacteria. |
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A Staphylococcus bacterium is Gram positive and lives in an oxygen-free habitat. To what phylum and class does it belong?
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Gram positive bacteria are in phylum Firmicutes.
Class Firmibacteria contains those Gram positive bacteria that are coccus-shaped. The oxygen-free information is irrelvevant, because respiration only matters in classifying Gram-negative bacteria. |
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Definition of:
Pathogen |
An organism that causes disease
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Definition of:
Saprophyte |
An organism that feeds on dead matter
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Definition of:
Parasite |
An organism that feeds on a living host
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Definition of:
Aerobic organism |
An organism that requires oxygen
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Definition of:
Anaerobic organism |
An organism that does not require oxygen
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Definition of:
Steady state |
A state in which members of a population die as quickly as new members are born
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Definition of:
Exponential growth |
Population growth that is unhindered because of the abundance of resources for an ever-increasing population
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Definition of:
Logistic growth |
Population growth that is controlled by limited resources
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Definition of:
Conjugation |
A temporary union of two organisms for the purpose of DNA transfer
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Definition of:
Plasmid |
A small, circular section of extra DNA that confers one or more traits to a bacterium and can be reproduced separately from the main bacterial genetic code
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Definition of:
Transformation |
The transfer of a DNA segment from a non-functional donor cell to that of a functional recipient cell
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Definition of:
Transduction |
The process in which infection by a virus results in DNA being transferred from one bacterium to another
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Definition of:
Endospore |
The DNA and other essential parts of a bacterium coated with several hard layers
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Definition of:
Strains |
Organisms from the same species that have markedly different traits
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Describe the functions of :
Plasma membrane |
To negotiate what materials pass into and out of the cell
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Describe the functions of :
Flagellum |
To move the bacterium from place to place
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Describe the functions of :
Capsule |
To adhere to surfaces as well as to ward off infection-fighting agents
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Describe the functions of :
DNA |
To store the information needed to make an organism a living thing
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Describe the functions of :
Cytoplasm |
To hold the DNA and ribosomes in place
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Describe the functions of :
Cell wall To keep the interior of the cell together and to hold the cell’s shape |
To keep the interior of the cell together and to hold the cell’s shape
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Describe the functions of :
Fimbria |
To grasp onto surfaces or another bacterium during conjugation
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Describe the functions of :
Ribosome |
To make proteins
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What is the most popular means by which bacteria obtain food?
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Most bacteria are heterotrophic decomposers
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If a bacterium is parasitic, is it heterotrophic or autotrophic?
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Parasites, by definition feed on something produced by a host. They therefore cannot make their own food. This makes them heterotrophic.
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List the basic steps in asexual reproduction among bacteria.
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At first:
the DNA loop attaches to a point on the plasma membrane After that, the DNA is copied, and the copy is attached to a point on the plasma membrane near the original. Then, the cell wall elongates, which separates the two loops of DNA. Once they are sufficiently separated, new cell wall and plasma membrane material grow, closing the two loops off from each other. Eventually, the cell wall and plasma membrane pinch down, forming two cells where there was only one before. |
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A sample of food is dehydrate, which kills all of the bacteria. However, in a few days, bacteria-free water is added to the food in a bacteria-free environment. Nevertheless, microscopic investigation indicate that bacteria are in the food. How did the bacteria get there?
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The bacteria that are there were in the food as endospores. The bacteria that were in the food before it was dehydrated formed endospores to survive a little while without water. When water was added to the food, the conditions were once again favorable for bacteria, so the cells burst from the endospores.
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What kind of growth does a population of bacteria experience when just a few of them are placed in an environment rich with resources?
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If the environment is rich with resources and there are only a few bacteria, the population will experience exponential growth, because there is nothing to limit their reproduction.
Since the growth is logistic, the resources are limited but do not run out. If the resources ran out, the population would experience a decline, and that is not a part of logistic growth. |
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Even though genetic recombination among bacteria does not result in offspring, it can significantly affect the growth of the population. Why?
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Genetic recombination can pass a trait from one bacterium to another. If that trait allows the recipient to survive conditions that it otherwise wouldn’t the population is affected, because the recipient continues to live and reproduce asexually.
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What are the technical names of the three common bacterial shapes?
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Coccus –Spherical
Bacillus – Rod-shaped Spirillum – Helical |
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A bacterium is heterotrophic and Gram-negative. To what phylum and class does it belong?
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If it is a Gram-negative, it is in phylum Gracilicutes. In this phylum, two classes contain photosynthetic bacteria, which are autotrophs. Since this bacterium is heterotrophic, it must belong to the only other class, class Scotobacteria.
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A spirillum bacterium is Gram-positive. To what phylum and class does it belong?
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Gram-positive means phylum Firmicutes. Since it is spirillum-shaped, it is neither coccus nor bacillus. Thus, it is in class Thallobacteria.
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A bacteria has no cellwall. To what phylum and class does it belong?
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Bacteria with no cell walls belong to the phylum Tenericutes, which has only one class, class Mollicutes.
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A bacterium lives in boiling-hot water. To what phylum and class does it most likely belong?
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This bacterium most likely is in phylum Mendosicutes and class Archaebacteria, because bacteria with exotic cell walls can survive conditions that other organisms cannot.
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In the six-kingdom classification system, what replaces kingdom Monera?
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In the six-kingdom system, kingdom Monera is split into kingdom Arcaebacteria and kingdom Eubacteria
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What conditions are ideal for most bacteria to grow and reproduce?
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To grow and reproduce, ideal conditions for most bacteria include:
Moisture moderate temperatures nutrition darkness proper amount of oxygen |
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What methods exist for reducing the chance of bacterial contamination of food?
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To reduce the chance of bacterial infection you can:
Heat the food so that most bacteria die and then seal it away from fresh air Dehydrate the food Freeze the food Pasteurize the food Keep it in the refrigerator |
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Two different species of bacteria attempt to infect an organism. One bacterium succeeds, while the other is destroyed by the organism’s infection-fighting mechanisms. What is most likely the major difference between these two bacteria?
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The bacterium that succeeded most likely has a capsule while the other does not.
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In bacteria, the capsule helps to protect the organism from infection-fighting mechanisms.
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A bacterium is poisoned by a substance that is allowed into the interior of the cell. What bacterial component did not do its job?
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The plasma membrane did not do its job.
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Since it regulates what moves in and out of the cell, it should not have allowed the toxin to enter
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If a bacterium cannot move, what structure is it missing?
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It is missing a flagellum.
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The fimbriae are not for movement; thus, if a bacterium has no flagellum, it cannot move
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Can saprophytic bacteria be autotrophic?
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No.
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Saprophytic means that it feeds on dead matter. Autotrophic organisms make their own food.
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Can an aerobic bacterium be chemosynthetic?
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Yes.
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Aerobic and anaerobic dal with how the organism converts its food into useful energy. Chemosynthetic deals with how the organism gets the food to begin with. Thus, the bacterium can make the food chemosynthetically and then convert it to useable energy aerobically.
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A population of bacteria grown from a single “starter” bacterium is rather fragile. When conditions are changed, the population dies quickly. Based on what you have just learned, developed a hypothesis for why this is the case.
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Since asexual reproduction allows no variation in the DNA, an entire population of bacteria started from a single bacterium have all the same traits. If the environment changes, and organism might need new traits to survive. Since the whole population has essentially the same traits, there is no way to get the needed new traits, and the population dies.
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The variability that exists in sexual reproduction usually makes a population much more resistant to changes in the habitat.
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A population of bacteria are living in a lake. Due to volcanic activity nearby, the lake’s temperature begins to increase. In the population, there are some bacteria that are resistant to low temperatures (call them type A) and another type that are resistant to high temperature (call them type B). Which type will be the donor and which the recipient as the population begins to conjugate?
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Type B will be the donors and type A will be the recipients.
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Since the bacteria will need to survive in high temperatures, they need resistance to high temperatures. That’s what will be donated.
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A bacterial colony is called staphylobacillus. What shape do the bacteria in the colony possess: spherical, rod-shaped, or helical?
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They are rod-shaped, since “bacillus” means rod-shaped.
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A bacterium has no cell wall. To what phylum does it belong?
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Tenericutes is the phylum for bacteria without a cell wall.
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A bacterium is classified as Gram-positive. To what phylum does it belong?
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Firmicutes contains all Gram-positive bacteria.
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A bacterium appears red after a Gram stain. To what phylum does it belong?
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Gracilicutes contains all Gram-negative bacteria. Since the bacterium appears red after the Gram stain, it is Gram-negative.
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A bacterium has a cell wall that is different form both Gram-positive and Gram-negative bacteria. To what phylum does it belong?
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Mendosicutes contains all bacteria with exotic cell walls.
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The term ______is often used as a general term that applies to all members of kingdom Monera.
Some are beneficial to humans, but some are _____, which means they cause disease. |
Bacteria
Pathogenic |
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Some bacterial have a ________that surrounds the cell wall. It is composed of an organized layer of sticky sugars that ________________________. It is also a protective layer that ____________.
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Capsule
help the bacteria adhere to surfaces deters infection-fighting agents |
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Most bacteria have a _______ that holds the contents of the bacterium together, regulates the amount of water that a bacterium can absorb, and holds the cell into one of 3 shapes _________, _________, or ___________. The absence or presence of a _________ as well as its composition (if it exists) are used to ______ bacteria.
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cell wall
spherical (coccus) rod-shaped (bacillus) helical (spirillum) cell wall classify |
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Underneath the cell wall (if it exists), there is a _____ ______,
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which regulates what the bacterium takes in from the outside world.
plasma membrane |
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________ exists throughout the interior of a cell, supporting the DNA and the ribosomes.
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Cytoplasm
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Many bacteria have fibrous bristles called _______, which are used for grasping. Locomotion is accomplished with a _________.
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Fimbriae
Flagellum |
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Ribosomes makes special chemicals known as _________.
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proteins
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In terms of what they eat, most bacteria are ________. As a result, they are called _______.
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Decomposers
Saprophytes |
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Some bacteria are _______, which means they feed on a living host.
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parasites
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Autotrophic bacteria manufacture their own food by either _________ (using the energy of the sun to make food) or __________ (promoting chemical reactions that release energy.
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Photosynthesis
Chemosynthesis |
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Some bacteria are ________, which means they need oxygen in order to survive. Some are ________, which means they do not need oxygen. The latter bacteria either _______ dead organisms or _____________ into chemicals that can be used by other life forms.
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Aerobic
Anaerobic Decompose convert useless chemicals |
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Asexual reproduction in bacteria is often called ___________.
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binary fission
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Typically, a population of bacteria starts off with __________ growth until it reaches a ___________ in which bacteria die as quickly as new ones are made. When population growth is controlled by resources, we call it __________. If resources begin to run out, the population will _______.
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exponential
steady state logistic growth decrease |
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When bacteria exchange genetic information, we call it ___________, and it can occur in one of three ways: _______, _________, or _________.
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genetic recombination
conjugation transformation transduction |
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In _________, bacteria link together to exchange circular strands of DNA called ___________. In __________, a bacterium can absorb a segment of _______ from a non-functional ________. In ________, DNA can be transferred from one bacterium to another by a virus.
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Conjugation
Plasmids Transformation DNA Bacterium Transduction |
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Bacteria can survive harsh conditions by forming ________.
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Endospores
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A ___________ is really just a simple association of individual bacteria. Bacteria in a streptococcus colony have a __________ shape, while bacteria in a diplobacillus colony have a __________ shape.
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bacterial colony
spherical (coccus) rod (bacillus) |
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After a ________, certain bacteria look blue when viewed under a microscope whereas others looked red.
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Gram stain
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___________ bacteria belong in phylum Gracilicutes, while _________ bacteria belong in phylum Firmicutes. Bacteria with cell walls significantly different from those in these two phyla belong in phylum __________., while bacteria with no cell walls belong in phylum __________.
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Gram-negative
Gram-positive Menodsicutes Tenericutes |
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Phylum Gracilicutes has 3 classes: _________ (non-photosynthetic bacteria)), ________ (photysynthetic bacteria that do not produce oxygen), and ___________ (photosynthetic bacteria that product oxygen). Phylum Firmicutes has two classes: __________ (cocci and bacilli bacteria) and _______ (bacteria of any other shape). Phylum Tenericutes has only one class: _______. Phylum Mendosicutes has only one class: ________. Many places that are uninhabitable to together organisms will be populated with members of class __________.
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Scotobacteria
Anoxyphotobacteria Oxyphotobacteria Firmibacteria Thallobacteria Mollicutes Archaebacteria |
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Photosynthetic organisms called blue-green algae are more properly called _______
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cyanobacteria
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Clostridium botulinum can cause botulism. Undercooked eggs and poultry can give you ________ poisoning. Escherichia coli bacteria live in your gut. There are pathogenic strains and non-pathogenic _________ of this bacterium.
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Salmonella
Strains |
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For optimum growth, most bacteria need ________, _________, _________, _______, and the __________________________.
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Moisture
Moderate temperature Nutrition Darkness proper amount of oxygen |
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For optimum growth, most bacteria need ________, _________, _________, _______, and the __________________________.
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Moisture
Moderate temperature Nutrition Darkness proper amount of oxygen |
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