SmithLifeScience Name __________________ Period _____
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Reading
Study Guide 21-2 Studying Populations Pages 711-718 |
1.- 8. Section 1 Vocabulary Matching (pages 711-718)
| Key Terms | ||
| _____ Birth Rate | A. approximation of a number, based on reasonable assumptions | |
| _____ Carrying Capacity | B. number of births in a population in a certain amount of time |
|
| _____ Death rate | C. number of deaths in a population in a certain amount of time | |
_____ Emigration |
D. moving into a population |
|
_____ Estimate |
E. leaving a population |
|
_____ Immigration |
F. number of individuals in area of a specific size |
|
_____ Limiting factor |
G. an environmental factor that causes a population to decrease |
|
_____ Population Density |
H. largest population that an area can support |
9. What's the Population of the
Beans in the Jar?
Your goal is to determine the population of beans in the jar.
You will have 2 minutes to estimate your answer.
You will not have time to count every bean.
You may use any of the following to help you:
My group estimates that the bean population is __________
Explain how you figured out your answer.
Determining Population Size p.712-713
10-13 Match the example to the method of determining population size.
_____ Direct Observation
A. Catch sea turtles, mark them with a dot, and release.
Return later and capture turtles again.
Count the numer of marked and unmarked turtles.
Use a math formula to estimate the population
_____ Indirect Observation B. Count all the crabs ina tide pool.
_____ Sampling
C. You count 120 cliff swallow nests.
The average nest holds 2 adults and 2 offspring.
Multiply the number nest 120 X 4 the number of birds
480 cliff swallows
_____ Mark-and-Recapture Studies
D. You count 8 birch trees in 100 sq meters of a forest.
The entire forest is 100 times larger.
8 birch trees X 100 = 800 birchtrees.
Changes in Population Size p.714-716
Choose from:
Dying
Decreases
Increases
Being born
14. The main way in which new individuals join a population is by _____________________.
15. The main way in which new individuals leave a population is by _____________________.
16. If Birth Rate is greater than Death Rate, the population size ____________________.
17. If Death Rate is greater than Birth Rate, the population
size ____________________.

Look at the Rabbit Population Graph on page 715
18. Did the rabbit population increase or decrease from Year 0 to Year 4? ______________
19. Did the rabbit population increase or decrease from Year 4 to Year 8? ______________
20. Give one reason why the rabbit population could decrease.

Population Density p.716 Figure 8 Flamingos
The pond on the left has 10 flamingos in 8 square meters.
To find the population density divide 10 flamingos by 8 square meters.
The population density is 1.25 flamingos per square meter.
21. What is the population density of the flamingos in the pond on the right on p.716? ________
Limiting Factors p.716-718
22.-25. Name 4 limiting factors for populations.
Evaluation
What method of determining population size would you use to count the following?
Use #10-13 to help you
26. grizzly bears in a national park? _________________________
27. grasshoppers in a field? ___________________________
28. herons in a large pond? __________________________

29. Birth Rate minus the Death Rate equals the Growth Rate.
Suppose 1,600 snow geese died in the same year
that 1,400 snow geese were born.
What would the Growth Rate for the snow geese
be for that year? ________

30. An oyster bed is 100 meters long and 50 meters wide.
In a 1 square meter area you count 20 oysters.
What is your estimate of the population of
oysters in the bed?

31. Suppose you counted 20 monarch butterflies in a garden
measuring 10 square meters.
What would the population density of the monrach butterflies be? ____________________