Population Graphing Assignment 1
Data Set 1: After a severe rainstorm, a small lake was formed in an abandoned quarry pit. Soon
2 beavers – 1 male and 1 female – move into the lake. There is plenty of food. There are also no
other animals that can affect the 2 beavers. The beavers build a home and produce 4
offspring. The population of beavers start to grow, as described.
1. Every spring, each pair of beavers produces 4 offspring, 2 male and 2 female
2. All parents die each winter. Only the offspring survive to reproduce.
3. None of the offspring during the winter. None of the beavers migrate.
4. There is ample supply of food.
Determine the population in the spring for the first 5 years. Use this information to draw a graph
with population on the y axis, and year on the x axis.
Year
Number of Parents
Breeding Pairs
Number of offspring
Population the next spring
0
1
2
3
4
5
2
4
8
1
2
4
8
4
8
Questions:
1. Describe the pattern of growth of the beaver population.
2. Do you think actual populations in nature grow like this hypothetical beaver
population? Give 3 reasons to support your answer
3. What do you think would happen to the growth pattern of this population if the
conditions stated that there was only enough food to support 50 beavers? Explain.
4. What would happen if another animal in a similar niche were added to the
ecosystem?
Growth of Bacteria population
in a Test Tube
Time
Population (#
(hours)
of bacteria)
0
150
1
190
2
380
3
700
4
1450
5
3000
6
5600
7
7000
8
7600
9
7650
10
7400
11
6600
12
6100
13
5500
14
5300
15
5400
16
4600
17
5500
18
5300
19
5400
20
5500
Data Set 2: Bacteria was added to a nutrient medium in a test
tube and allowed to grow. The resulting culture monitored, and
every hour the number of bacteria in a drop was counted. The
following data was obtained. Graph the data on a piece of graph
paper.
Questions:
1. Describe how the population changed for the first 7
hours.
2. What happens to the population after 9 hours? How is
this different from the first 7 hours? Why do you think this
change occurred?
3. What happens to the population for the last 5 hours –
does it increase, decrease or stay about the same? Why
do you think this is?
4. Draw a line representing the average population of the
test tube for the last five hours. This number is the
carrying capacity of the test tube. About how many
bacteria can the test tube support?
5. What factors might affect the number of bacteria that
the test tube can support?
6. After 100 hours, the population of the test tube fell to
zero. Why do you think this is?
7. Describe of a real world example of carrying capacity.
.
Communication
Graphing Conventions
Level 4
Excellent
Level 3
Very Good
Level 2
Satisfactory
Level 1
Poor
Answers in Complete Sentences
Excellent
Very Good
Satisfactory
Poor
Spelling Grammar
Excellent
Very Good
Satisfactory
Poor
Neatness
Excellent
Very Good
Satisfactory
Poor
Application
Part 1 questions answered with
insight and depth
Part 2 questions answered with
insight and depth
Level 4
Excellent
Level 3
Very Good
Level 2
Satisfactory
Level 1
Poor
Excellent
Very Good
Satisfactory
Poor
Communication
Graphing Conventions
Level 4
Excellent
Level 3
Very Good
Level 2
Satisfactory
Level 1
Poor
Answers in Complete Sentences
Excellent
Very Good
Satisfactory
Poor
Spelling Grammar
Excellent
Very Good
Satisfactory
Poor
Neatness
Excellent
Very Good
Satisfactory
Poor
Application
Part 1 questions answered with
insight and depth
Part 2 questions answered with
insight and depth
Level 4
Excellent
Level 3
Very Good
Level 2
Satisfactory
Level 1
Poor
Excellent
Very Good
Satisfactory
Poor
Communication
Graphing Conventions
Level 4
Excellent
Level 3
Very Good
Level 2
Satisfactory
Level 1
Poor
Answers in Complete Sentences
Excellent
Very Good
Satisfactory
Poor
Spelling Grammar
Excellent
Very Good
Satisfactory
Poor
Neatness
Excellent
Very Good
Satisfactory
Poor
Application
Part 1 questions answered with
insight and depth
Part 2 questions answered with
insight and depth
Level 4
Excellent
Level 3
Very Good
Level 2
Satisfactory
Level 1
Poor
Excellent
Very Good
Satisfactory
Poor
Level R
Very Poor
/Incomplete
Very Poor
/Incomplete
Very Poor
/Incomplete
Very Poor
/Incomplete
Level R
Very Poor
/Incomplete
Very Poor
/Incomplete
Level R
Very Poor
/Incomplete
Very Poor
/Incomplete
Very Poor
/Incomplete
Very Poor
/Incomplete
Level R
Very Poor
/Incomplete
Very Poor
/Incomplete
Level R
Very Poor
/Incomplete
Very Poor
/Incomplete
Very Poor
/Incomplete
Very Poor
/Incomplete
Level R
Very Poor
/Incomplete
Very Poor
/Incomplete