Unit 14 Test Review
Viruses, Bacteria, and Immunity
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Name ___________KEY_________________
V for Viruses
B for Bacteria
Use the terms above to fill-in the blanks.
__V___ 1. They cause chicken pox.
__B___ 2. They can grow/develop, reproduce, and
can adapt/evolve
__B___ 3. They are made of cells.
__B___ 4. They are prokaryotic.
__B__ 5. They are the oldest forms of life on earth.
__V__ 6. Most biologists agree they are not alive.
__B___ 7. They can cause strep throat.
__V___ 8. They need a living host to reproduce.
__B___ 9. They are used to make some foods.
__B___ 10. Antibiotics will work against them.
11. What is the structure that bacteria form during adverse conditions or when harsh environmental changes
occur? _ENDOSPORE___________________________
12. Bacteria produce chemical poisons called _TOXINS_ which can be very harmful to the host organism.
13. Bacteria do not have nuclei and cannot go through mitosis or meiosis in order to reproduce, but they do
reproduce through a cycle called ___BINARY FISSION________________________________.
14. Bacteria can pass on genetic information to one another via a structure called a pilus. This process is
called ___CONJUGATION________________________________.
15. One major piece of information that bacteria exchange is ___ANTIBIOTIC__________________
resistance which is causing major alarm in the medical communities.
16. What are some of the “super” bugs or resistant bacteria that medical professionals are currently very
concerned about?
MRSA, CDIF bacteria which traditional antibiotics don’t work against. Very hard or impossible
to treat these infections.
17. What process did these “super” bugs use in order to pass on this resistance to one another?
Conjugation
18. What are the two kingdoms of bacteria?
ARCHAEBACTERIA and EUBACTERIA
19. What are some of the differences between those two kingdoms?
ENVIRONMENTS IN WHICH THEY CAN SURVIVE. Archaebacteria live in extreme
environments and eubacteria live where we live.
20. All bacteria are prokaryotic organisms. What does this mean again??
DO NOT HAVE A NUCLEUS OR MEMBRANE BOUND ORGANELLES; All unicellular
21. What are some of the ways that eubacteria obtain their food?
PARASITES – feed on live things
SAPROPHYTES – feed on dead things and waste products
AUTOTROPHS – make their own food through photosynthesis or chemosynthesis
22. What is the major difference between obligate aerobes and obligate anaerobes?
OBLIGATE AEROBE – REQUIRE OXYGEN
OBLIGATE ANAEROBE – KILLED BY OXYGEN
23. What is the major difference between gram-positive bacteria and gram-negative bacteria?
GRAM POSITIVE = TURNS PURPLE b/c thin or no cell walls
GRAM NEGATIVE = TURNS PINK b/c thick, resistant cell walls
24. Why would it be important for a physician to know what type of bacteria are present?
SO THEY CAN TREAT WITH THE RIGHT ANTIBIOTIC TO BREAK DOWN THE CELL
WALL.
25. Fill in the diagram below with the correct bacterial shapes.
COCCUS
SPIRILLUM
BACILLUS
26. What are some of the benefits to having bacteria around? (What good things do they accomplish?)
FOOD PRODUCTION (pickles, sauerkraut, yogurt, cheese, etc.)
RECYCLING OF NUTRIENTS (decomposers and saprophytes)
MEDICINE (insulin production and development of antibiotics)
Nitrogen Fixation – (turn forms of nitrogen into forms usable by plants)
27. What is an antibiotic? What organisms will antibiotics work against?
An antibiotic is a medicine/chemical designed to kill foreign invaders in the body. ANTIBIOTICS
WORK AGAINST BACTERIA BREAKING DOWN THE CELL WALL.
28. What antibiotic was discovered by Fleming in 1928? ___________Penicillin_______________
29. How do antibiotics work against bacteria?
Some antibiotics like penicillin work by keeping a bacterium from building a cell wall.
Without support from a cell wall, pressure inside the cell becomes too much and the
membrane bursts. Other antibiotics block bacterial ribosomes and prevent them from
building proteins. Since proteins do all the cell’s work, a bacterium that cannot build
proteins cannot survive.
30. Use the following words for the chart to below. Place the correct word underneath the correct title it
aligns with.
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Lytic Cycle
Coccus
Binary Fission
Conjugation
Lysogenic Cycle
Nucleic Acids (DNA/RNA)
Capsid
Alive
Obligate anaerobe
Made of cells
Can cause disease
Food production
Coccus
Binary Fission
Conjugation
Nucleic Acids (DNA/RNA)
Food production
Alive
Obligate Anaerobe
Made of cells
Can cause disease
Lytic Cycle
Lysogenic Cycle
Nucleic Acids (DNA/RNA)
Capsid
Can cause disease
31. Look that the graph below with the different lines on it and answer the following questions.
2
1
Number
of
Bacteria
3
Time
Which line could represent a bacterial colony that has been given an antibiotic? _3_____
Which line could represent bacterial growth in the presence of abundant resources (food and water)? _2___
32. What is the name of the cell that the virus infects and takes over during its replication cycle?
Host cell
33. A virus that infects a bacterium would be called a/an _____bacteriophage_______________________.
34. A virus that uses DNA as its nucleic acid is called a/an ____DNA_____ virus.
35. A virus that uses RNA as its nucleic acid is called a/an ___retrovirus_____________.
36. The infected cell that forms when viral DNA incorporates into the cell’s DNA is called a _provirus___.
C
E
B
D
A
Virus attaches to host cell and injects its nucleic acid into the cell.
The viral DNA/RNA is integrated (becomes part of) the host cell chromosome-called a provirus
Each time the host cell replicates the provirus is replicated as well.
2
1
5
4
3
37. What are some examples of viruses that go through the lytic cycle?
Common Cold, Influenza (FLU)
38. What are some examples of viruses that go through the lysogenic cycle?
Herpes, HIV
39. The cell is killed during the ____Lytic___ cycle whereas the cell is not killed during the
____Lysogenic_____ cycle.
40. Symptoms for the ____Lytic____ cycle show up usually in 2-4 days, whereas symptoms for the
_____Lysogenic________ cycle can take years to show up.
41. Viruses are (smaller or larger) than bacteria.
Immunity
42. Any foreign substance that can cause the immune response in humans would be considered a/an
_______Antigen____________.
43. Examples of substances/organisms that cause the immune response would include:
Bacteria, Viruses, Fungi, Allergens (ragweed, dust, cat dander, etc.)
44. What are antibodies? What do they do for humans?
Proteins formed by white blood cells that circulate the body and help us recognize foreign
invaders to be killed off by our immune system. They fight infection and form after being
exposed to an antigen one time prior or through vaccination.
45. What is a pathogen? What are some examples?
Any disease causing agent is a pathogen. Bacteria, Viruses, Fungi, Protozoan are all examples.
46. What is a vaccine?
An injection/nasal liquid, etc. that is taken artificially to stimulate the production of
antibodies against a certain pathogen. The goal is to stimulate immune memory so that if later
infection occurs, the disease does not occur or is significantly less dangerous that it would
have been without the vaccine.
47. What can your immune system do if you are infected with a pathogen?
Your immune system will first do what it can to kill, engulf foreign pathogen. Later B cells
will form antibodies to create memory of disease and will help later prevent infection by this
certain type of pathogen.
Infectious disease is the chief cause of death in developing countries. More antibiotics would be available in
developed countries because they have access to regular medical care. You would then expect numbers of
infectious diseases to decrease which is evident in the graph. Developing countries would have higher rates
of infectious disease for lack of appropriate medical care.
Lack of appropriate medical care, poor nutrition or starvation, and infected water supply.
Also highly dense populations where lots of people are in close proximity can lead to fast disease transmission.
Doctors advise patients on antibiotics to take yogurt because yogurt contains active cultures (probiotics) of bacteria
that are useful for digestion and nutrient absorption. The antibiotics they are taking would kill any existing bacteria,
so they would need to be replaced. Yogurt can do that.
Two reasons why yes - bacteria have cell walls just like plants do; some bacteria are photosynthesizers like plants
Two reasons why not – bacteria are prokaryotes not eukaryotes like plants; some bacteria are heterotrophs