Science: Microorganisms: Bacteria, Viruses, and Fungi
Comparing tiny life forms and disease-causing agents
Science: Microorganisms: Bacteria, Viruses, and Fungi
Comparing tiny life forms and disease-causing agents
Biology - Grade 6-8
- 1
Explain one main difference between bacteria and viruses.
Think about whether each one can reproduce on its own.
One main difference is that bacteria are living single-celled organisms, while viruses are not considered living cells and must use a host cell to reproduce. - 2
A student says that all microorganisms are harmful. Is this correct? Explain your answer using an example.
This statement is not correct because many microorganisms are helpful. For example, some bacteria in the human gut help digest food and support health. - 3
Name one way fungi are different from bacteria.
Think about the number of cells in each type of organism.
One way fungi are different from bacteria is that fungi can be multicellular, such as molds and mushrooms, while bacteria are single-celled organisms. - 4
Why are antibiotics used to treat some bacterial infections but not viral infections?
Antibiotics are used to treat bacterial infections because they target structures or processes in bacteria. They do not work on viral infections because viruses reproduce inside host cells and do not have the same cell structures as bacteria. - 5
A loaf of bread grows fuzzy green mold after being left out for several days. Is the mold a bacterium, a virus, or a fungus? Explain how you know.
Bread mold belongs to the same broad group as mushrooms and yeast.
The mold is a fungus. Mold is a type of fungus that grows on food and often appears fuzzy or powdery. - 6
Describe how a virus reproduces.
A virus reproduces by entering a host cell and using the cell's machinery to make more copies of itself. It cannot reproduce independently. - 7
Give one example of a useful role of fungi in nature or human life.
Think about what happens to dead leaves and logs in a forest.
One useful role of fungi is that they decompose dead material and recycle nutrients back into the environment. Some fungi are also used to make foods such as bread and cheese. - 8
What is one structure that bacteria have which viruses do not?
Bacteria have a cell membrane and cytoplasm, while viruses do not have full cell structures like living cells do. - 9
Why is washing your hands an effective way to reduce the spread of many microorganisms?
Think about how germs move from surfaces to your mouth, nose, or eyes.
Washing your hands helps remove microorganisms from your skin before they can enter your body or spread to other people and surfaces. - 10
Compare bacteria and fungi by naming one similarity and one difference.
One similarity is that both bacteria and fungi are microorganisms. One difference is that bacteria are single-celled, while fungi can be single-celled or multicellular. - 11
A doctor says a patient has athlete's foot. Which group of microorganisms causes this condition: bacteria, viruses, or fungi?
This condition is commonly treated with antifungal medicine.
Athlete's foot is caused by fungi. It is a fungal infection that grows well in warm, moist environments. - 12
Explain why scientists often use microscopes to study bacteria, viruses, and many fungi.
Scientists often use microscopes because bacteria, viruses, and many fungi are too small to be seen clearly with the naked eye. Microscopes help scientists observe their size, shape, and structures.