Download 6 microbe reading questions KEY

Name: ______________________________
Date: ______________ Period: _________
Lesson 6 Reading Questions: Microbes
Read the provided reading packet and answer the questions below.
1. Would you describe bacteria as being helpful or harmful to people? Explain.
Answers vary. Most correct answer: They are both helpful and harmful to people because they help
us digest foods, they’re used to make medicine and food but they can also cause disease that people
can die from.
2. Why are viruses not considered to be microorganisms?
Viruses are not considered living because they cannot reproduce on their own. They are genetic
material covered in a protein coat. Microorganisms are small living things therefore viruses are not
microorganisms. Not technically a cell
3. Look at the figure on page 33 “Comparing Average Sizes of Microbes”. How do the sizes of protists,
bacteria, and viruses compare?
Protists are the largest, bacteria are in the middle, and viruses are the smallest.
4. Which do you think cannot be seen with a classroom microscope?
Viruses require an electron microscope to view
5. Follow these directions using the table below.
a. In each list, look for a relationship among the words. Cross out the word or phrase that does not
belong.
b. In each list, circle the word or phrase that includes the others.
List 1
List 2
List 3
Animals
Animal cell (cross out)
Protists
Bacteria
Cell wall
Bacteria (cross out)
Plants
Plant cell (circle)
Animals
Protists
Chloroplasts
Plants
Respire (circle)
Mitochondria
Eukaryotes (circle)
Viruses (cross out)
Nucleus
nucleus
c. Explain how the word or phrase you circled is related to the other words on the list:
List 1: Animals, bacteria, plants, and protists are all living things which respire. Viruses are not living and
do not respire.
List 2: Only plant cells have all the organelles shown, including chloroplast, so animal cells do not fit on
the list.
List 3: Protists, animals, and plants are all eukaryotes and have nucleus. Bacteria do not have a nucleus
and are not eukaryotes.
6. You have read how microbes can be both helpful and harmful to humans. Do you think a microbe
can be neither helpful nor harmful? Explain. Answers vary. Mostly likely answer: some
microorganisms do not have a positive or negative effect on people. For example, the paramecium is
neither helpful nor harmful to people.
7. You decide to examine some pond water under a microscope. With a magnification of 40 (using the
4X objective), you observe a long, cylindrical organism moving across your field of view. As you look
more closely, you notice what appears to be a round structure inside of it. Is this organism most
likely a protist, bacterium, or virus? Explain how you arrived at your conclusion.
This organisms is most likely a protist. Evidence that support this conclusion is the presence of what
appears to be a nucleus inside of the organism. Viruses and bacteria do not have a nucleus.
8. Suppose your school’s microscopes did not have a 40x objective, but only 10x objectives. Your
friend, who is in high school, uses a 40x objective. What is a group of microbes that your friend can
study that you cannot? Bacteria. Most bacteria are extremely tiny and require a high level of
magnification (such as 400x, like our high power). Protists are larger and can be seen with a lower
level of magnification so they could be seen with both microscopes.
9. What are the advantages of using the highest power objective on a microscope? What are the
advantages of using the lowest power objective on a microscope? Explain.
On high power, you can see more details. On low power you have a larger field of view and it is
easier to focus and find organisms.
10. In the Venn diagram below, record unique or important features of each group of microbes in the
appropriate space. Record common features among group sin the spaces that overlap. (Hint: think
about what you have learned about cells in the last few activities.)
Protist
Nucleus,
organelles,
largest
Bacteria
Living, cell
membrane,
one cell,
cytoplasm
Genetic
material,
microbes
Not living, not a cell,
smallest
Viruses
smaller than
protists
Genes
not in
nucleus