Microbiology Final Quiz
Review
Topics to Review www.rosedalegrade11collegebiology.wikispaces.com
· Immune system
· Fungus kingdom
Practice Questions
1. Circle (T) true or (F) false for each of the following statements. If it is false rewrite it to make it true.
T/F Lymphocytes are white blood cells that engulf and destroy disease-causing microorganisms.
True
T/F The human body has many defences against infection. The first line of defence is an external physical barrier such as the skin.
True
T/F A disease-causing microorganism is called a pathogen. It causes symptoms that result from tissue destruction and from the body’s response to its invasion.
True
T/F Many bacteria enter the body through the nasal passage or the pharynx. Specialized cells equipped with flagellum sweep the trapped bacteria or debris upward which coughing expels.
False.Hair-like structures (cilia) sweep this mucus into the throat for coughing or swallowing
T/F Macrophages are white blood cells that make antibodies. They are produced by lymph nodes in the lymphatic system.
False. Macrophages do not make antibodies.
2. Answer the following questions.
(a) What is the difference between passive and active immunity?
- Passive immunity – antibodies acquired from mother’s milk
- Active – you produce them (either from a vaccine or an illness)
(b) What is the difference between an antigen and an antibody?
An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibodies..
An antibody is a large protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses.
3. Infectious diseases spread from one individual to another in a variety of way. List three (3) modes of disease transmission.
- Air
- Sexually transmitted (body fluids)
- Water
- Break in the skin
- fecal - oral
4. What ecological role do fungi play?
Fungi perform an essential role in the decomposition of organic matter and have fundamental roles in nutrient cycling and exchange. They have long been used as a direct source of food, such as mushrooms and truffles, as a leavening agent for bread, and in fermentation of various food products, such as wine, beer, and soy sauce.
5. List 6 features of fungi that originally placed them in the plant kingdom.
Cell wall, eukaryotic, anchored in soil, stationary, sexual reproduction, numerous organelles
6. Draw and label a diagram of a fungus and explain why the mycelium of a fungus may be present but unnoticed.
Mycelium may grow underground and go unnoticed.
7. Summarize the uses of yeast. Refer to the unit opener on page 93 of the textbook.
Used for production of bread, wine and cheese.
8. In a mould growth experiment, bread cubes were moistened with water at three different pH levels. Temperature was kept constant. The number of colonies was counted and recorded daily during a one week period. Bread mould is Rhizopus.
Day / Number of Mould ColoniespH 4.0 / pH 5.5 / pH 7.0
Start / 0 / 0 / 0
1 / 0 / 8 / 1
2 / 1 / 14 / 2
3 / 2 / 24 / 3
4 / 2 / 32 / 3
5 / 2 / 40 / 3
6 / 3 / 48 / 4
7 / 3 / 48 / 4
a) Arrange the data in a line graph. Plot days of growth on the x-axis and number of mould colonies on the y-axis. Draw three separate lines for each of the pH values.
b) According to the data, what pH is optimum for bread mould growth?
pH 5.5
c) Temperature was controlled in this experiment. Name three other factors that also need to be kept constant in order for the above conclusion to be valid.
- amount of bread, number of days, amount of water added
d) Bread mould is a saprophyte. What evidence suggests that bread is a suitable food for this organism?
- mold grew
e) What environmental conditions would you recommend to prevent mould growth on foods?
- keep food cold and at neutral or acidic pH levels