Laboratory Seven Ecological Niche
Section T6 Biology 1010: Fall 2016
Laboratory Seven: Ecological Niche
Student Name:______________
Lab section: ________________
Lab instructor Name: ____________
Last 4 digits of your CUNYFirst Empl ID #: ___________________ Directions:
1. Click on the link in the Lab 7 simulation to get to the lab.
2. Read the web page to help you understand the material in this lab before starting
the experiments.
3. Utilize the links on the bottom of the web page to conduct experiments to
determine the optimum temperature and pH for the four microbes below that
match the last 4 numbers of your CUNYFirst ID number.
4. You must study four different microbes. If you have duplicate numbers, or 0 or 9
in your ID number, pick one or more additional microbes randomly.
THE LIST OF ORGANISMS:
1. Rambies uglitus
2. Falitius rebrantus
3. Scribio euglensis
4. Pseudomonas retii
5. Neisseria atol
6. Sulfolobus litia
7. Leuconostoc botolus
8. Escherichia coli
5. Use the links at the bottom of the web page to begin growing cells to determine
the optimum conditions for each microbe.
6. Record the results in the Tables of Results (Temperature, pH) provided on the
following pages. Read the instructions on the top of each table carefully. 1 Section T6
Part One: Definitions and Background information 1. Define the term niche. (0.4 pts) 2. Name three resources for which organisms might compete. (0.6 pts) 3. Define evolution. (0.5pts) 4. How might evolution be affected by competition? (0.5pt) 2 Section T6
Part Two: Results Generated from the Ecological Niche Web Page
Table 1: Effects of Temperature on Microbial Growth
In the top row place the names of the 4 microbe that you will be studying (matching your
ID number). For each temperature enter the LOG VALUE of GENERATIONS per
HOUR (do not use generations per minute). Negative numbers should be recorded as 0.
(1 pt)
Temp 0
5
10
15
20
25
30
35
40
45
50 3 Section T6 55
60
65
70
75
80
85 4 Section T6
Part Three: Results Generated from the Ecological Niche Web Page
Table 2: Effects of pH on Microbial Growth
In the top row, place the 4 microbe names that match your student ID number. For each
pH, enter the LOG VALUE of GENERATIONS per HOUR (do not use generations per
minute). Negative numbers should be recorded as 0. (1 pt)
pH
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5 5 Section T6 7
7.5
8
8.5
9
9.5
10 6 Section T6
Part Four: Data Analysis
Direction: Fill in Table 3 with the optimal pH and temperature for each of your four
microbes using your data from tables 1 and 2.
Note: the highest log value equals the optimum pH or temperature. (2 pts)
Table 3: Optimal Temperature and pH for each microbe
Microbe Optimal Temperature Optimal pH Direction: Fill in table 4 with the highest and lowest temperatures and pHs that show
growth for each microbe, using your data from tables 1 and 2. (2 pts)
Table 4: Fundamental Niche
Microbe Lowest temp
showing
growth Highest Temp
showing
growth 7 Lowest pH
showing
growth Highest pH
showing growth Section T6 Part Five: Graph
Direction: Construct a graph demonstrating
a. The fundamental niche (this is the temperature and pH range in which the
cells can grow) and
b. The optimum niche for each microbe with respect to temperature and pH.
The fundamental niche will be shown as a box on your graph – the height of box covers
the whole pH range of the microbe’s growth, and the width covers the whole temperature
range. Your complete graph will have four boxes, one for each microbe. The optimum
niche for each microbe will be a point on the graph (which shows the optimum pH and
temperature). (4 points)
Questions:
1. How can you use your graph to determine which organisms will be in competition?
(0.5 pts.) 8 Section T6 2. Using this information, determine which of the organisms you have studied are in
competition. List the organisms in competition and indicated the ranges in which
they compete? (0.5 pts.) 3. What is the significance of the optimal temperature and pH for each microbe? (1
pts.) 4. What would happen if all of your microbes were put into a test tube at 27 degrees at
a pH of 7.4? Would there be competition? Which microbe or microbes would
survive? ? (1 pts.) 9
USA 
India