Download biodiversity

“Do Now”
 Take out a sheet of paper and answer the following
questions:
What are some reasons that a population’s growth is
limited?
2. What is the disadvantage of a rapid growth in human
population?
3. Explain the relationship and trend between predator and
prey population in an ecosystem.
1.
Biodiversity
 Definition: number and
variety of species on
Earth
 1.6 million known
species on Earth
 Most are insects
 Scientists believe there
are >13 million species
now living
Humans & Biodiversity
 Population of world is
increasing at rate of
220,000 people each day
 Because increase in
human population,
species become extinct
at faster rate
Humans & Biodiversity
 Why does the increase in human population have such
a large effect on other species?
 Humans struggle with other species for resources
 Main causes of species extinction:
1. Destruction of habitats (75% of extinctions)
2. Unregulated hunting
3. Introduction of nonnative (exotic) species
What species are affected by this
destruction of habitat?
Exotic Species
 Definition: species not
native to a particular
region
 Ex: penguins would be an
exotic species in farmlands
 Exotic species can threaten
native species
 Native species develop
specific defenses to survive
in their environment
 Example: Melaleuca tree in
Florida
Value of Biodiversity
 Why is it important to slow down the rate of
extinction?
1. Preserves Ecosystems
 Keystone species= species that are extremely important
to the function of ecosystem

i.e. sea otter
2. Practical Uses of Species
 Medicine, treatments, food, etc.

i.e. Taxol from Pacific Yew Tree  treats some cancers
3. Ethical & Aesthetic Reasons
Biodiversity – True or False?
 Answers
 9. true
 10. false
 11. false
 12. true
 13. false
 14. true
 15. true
Group Assignment
 Read Chapter 5 in the textbook
Page 129: Write definitions for the vocab terms
2. Page 130: “Understanding Key Concepts”(#6-9)
3. Pages 136-137: “Multiple Choice” (#1-9)
1.
**Write out all questions and answers. No credit will be
given for simply writing the answers.