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23 Cards in this Set

  • Front
  • Back
Developed countries have what % of the population?
20
Developed countries have what % of the world's wealth?
85
Developed use what percent of natural resources?
90
developed generate what percent of pollution and wastes?
75
developed countries generate what percent of the toxic wastes?
90
The US has about what percent of the world's population?
4.5
The US uses about what percent of the world's mineral and renewable resources?
25
of the desperately poor earning less than $1 a day, what ratio live in rural areas
2/3
what industry is responsible for 2/3 of world's annual freshwater use?
agriculture industry
what animal has no tissues, organs or symmetry?
Sponges
how many known species of animals are there?
2,000,000
first animals with organs?
flatworms
first animals with tissues?
cnidarians
most abundant on earth?
Roundworms
first animals with complete digestive system?
roundworms
are there more species of insects or roundworms?
insects
what is elephantiasis caused by?
plugged lymph nodes by roundworms
first animals with a body cavity (coelem)
mollusks
what is an annelid example?
earthworm (ringed)
what animals accounts for over half of the world's animal species?
arthropods
what are the 3 groups of arthropods?
insects, spiders and crustaceans
what were first vertebrates on land?
amphibians
are most chordates vertebrates or invertebrates?
vertebrates