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WorksheetsThreats to Biodiversity
Total questions: 10
Worksheet time: 12mins
_____________ extinctions occur naturally over time and do not concern scientists. Many are worried that the current extinction rate is about 1,000 times higher.
Background
Extinction
What has occurred during each of the Earth's mass extinctions?
Most of the Earth's islands have become uninhabited.
A new dominant species has been introduced to the Earth.
Humans hunted many animals for food and clothing.
The Earth has lost at least three-quarters of its species.
Some people believe that the Earth is currently experiencing its sixth mass extinction
because_____________
The background extinction rates are happening gradually
the Earth's climate has stayed relatively unchanged
The extinction rate has greatly increased due to human actions
There are now laws to protect the habitats of many species
Identify the human action that could potentially lead to habitat fragmentation.
recycling, reusing, and reducing waste to reduce pollution
animals hunting as a sport
cutting down some trees to build a road through a habitat
accidentally introducing a nonnative species to the habitat
Select the effects of habitat fragmentation on biodiversity. (2 answers)
increase in edge habitats
chances of finding a mate increase
carrying capacity increases
carrying capacity decreases
increase in interior habitats
Habitat fragmentation can negatively impact______ opportunities for species to find mates. diversity by reducing
Extinction
genetic
Background
In a typical food web, a(n)__________ of a pollutant in its body. is likely to have the lowest concentration
producer
genetic
Chemicals, like DDT, enter the tissues of animals by.
feeding on other organisms
living in an edge habitat
interacting with populated areas
breathing the chemicals in the air
Chemicals such as polychlorinated biphenyls (PCBs) enter ecosystems through__________
industrial runoff
producer
genetic
Bonus
LION
RYAN
SIMB
