1. 7B Warm-Ups August 24, 2009 #10 What is the MEAN length of the polar bears? 2.4 m 2 m 2.8 m 2.4 m

2. 1.Which type of these factors is a biotic factor in a forest ecosystem? a.temperature of the soil b.types of trees that grow there c.amount of precipitation each year d.amount of sunlight that reaches the ground 7B Warm-Ups August 25, 2009 #11

3. 2.Which of the following statements best describes a tropical rainforest? a.It has coniferous trees and little rainfall. b. It has permafrost and mosses. c.It has deciduous trees and ferns. d.It has diverse plant and animal life. 7B Warm-Ups August 26, 2009 #12

4. In polar tundra, the layer of soil beneath the surface soil stays frozen all the time is called ________________. 7B Warm-Ups August 24, 2009 #10 permafrost

5. What is the difference between a community and a population ? 7B Warm-Ups August 28, 2009 #14 A community is made of populations and populations are made of individual species

6. Pages 484,485,486