Bacteria Coloring Packet Follow-up
Integrated Science 2
Name:
Date:
Pd:
Directions: Using your Bacteria Coloring Packet, both the reading and the color plates, answer the following
questions about bacteria, their structure and how they reproduce.
Forms of Bacteria
1. The three bacterial forms are: _________________, ____________________ and ____________________.
2. Draw and label a sample of each of the three types, and give their approximate size.
3. Of the three forms, which are smallest? ___________________which are largest?__________________ How many
times larger?____________ times.
4. What does the prefix “strepto” mean? _____________________________________________________________
5. Based on your answer to #4, what do we deduce about “streptococcus”, one of the cultures used to make
yogurt?
Bacterial Ultrastructure
1. The flagellum is used for one purpose, what is it? _______________________________
2. What part of the bacterium is damaged by detergents? ________________________________
3. Pili (plural of pilus) are often confused with flagella, but they have a very different purpose. What do the
pili do for the bacteria?
4. How many chromosomes does a bacterium have? _________________
5. In addition to the chromosome, bacteria have DNA in dozens of plasmids. Describe this and draw an
example.
Bacterial Reproduction
1. Asexual reproduction of bacteria is called _________________ _______________.
2. Binary fission occurs after the cell has had a period of _______________________ and ____________________.
3. Bacteria go through similar reproductive stages as body cells do in mitosis. List the steps below.
First) Bacterium elongates
Last) cell separates into two halves (daughter cells) with identical DNA.
4. How does penicillin disrupt bacterial reproduction?
What ultimately happens to the exposed cell?
5. The amount of time needed for bacteria reproduction is unique for each species. How long does the
example bacteria on the color plate need to form daughter cells?
Let’s assume that you collect 10 live bacteria on your petri dish at noon. How many cells will you have by 5
PM? (careful! It’s not just 10 x 5!) Show your work.
Bonus: How many after 24 hours?
Bacterial Spores
1. Why would a bacterium produce spores?
Give some examples of places where spores are known to have survived.
2. What happens when the external environment for a spore is favorable (stable temperature, nutrients,
hydration)?
3. Some of the bacteria that we picked up around campus were actually bacterial spores. Why are we
sometimes more likely to pick up spores than live bacteria?
Why, then, were we able to see so much bacteria in our petri dishes on the 2nd day of the lab?