1
Almost all antibiotics are derived from chemicals in
Fungi
What are the three levels of biodiversity?
Species diversity, ecosystem diversity, and genetic diversity
In the past, Earth experienced many mass extinctions that were probably caused by
Global change in climate
The most threatened areas of high species diversity on Earth have been labeled as
What fraction of the drugs prescribed in the US are derived from plants?
1/4 (one quarter)
Most new crop varieties are what?
Hybrids, or crops developed by combining genetic material from other populations
What type of populations are vulnerable to infectious diseases and genetic disorders caused by inbreeding?
Small
Why is depending on too few plants for food risky?
Famines
Currently, mass extinction is caused by
Humans
Because of a pesticide called DDT
What do ecologists use as an indicator of overall biodiversity?
Even though they only cover 7% of the Earth's land surface, biologists estimate that over half of the world's species are located where?
Tropical rain forests
What is the approximate number of species known to science?
1.9 million
What is the most effective way to save species?
The rate of extinction has increased by a multiple of 50 since 1800, with what percent of all species on Earth becoming extinct between 1800 and 2100?
25%
Genetic diversity refers to?
All the different genes contained within all members of a population.
What percentage of extinction is caused by a species' habitat loss?
75%
List two of the four private organizations that work to protect species worldwide.
The World Wildlife Fund, The Nature Conservancy, Conservation International, and Greenpeace International
Wildlife experts may attempt to restore the population of a species through what?
Species diversity refers to what?
All the differences between populations of species, as well as between different species.
What are living museums of the world's biodiversity (4 answers)?
Zoos, wildlife parks, aquariums, and botanical gardens
Biodiversity can affect the stability of ecosystems and
What type of areas do unknown species exist (3 answers)?
Remote wilderness, deep oceans, some cities
Ecosystem diversity refers to what?
The variety of habitats, communities, and ecological processes within and between ecosystems.
What happens when one species disappears from an ecosystem?
A strand in a food web is removed.
From the notes, what pollutants are making their way into food webs (4 answers)?
Pesticides, cleaning agents, drugs, and chemicals
List two of the common medicines derived from plants and their use (medicine name and origin).
Ex: neostigmine from the calabar bean used to treat glaucoma
taxol from the Pacific yew used as an anti-cancer agent
cortisone from the wild yam used as a hormone in many drugs
Nearly 60% of Earth's coral reefs are threatened by human activities such as (3 answers)?
Pollution, development along waterways, and overfishing
Species that are especially at risk of extinction are (3 answers).
Those that migrate, those that need large or special habitats, and those that are exploited by humans.
When was the Endangered Species Act passed?
1973
Explain the four main provisions of the Endangered Species Act.
First provision - The U.S. Fish and Wildlife Service must compile a list of all endangered and threatened species in the US.
Second provision - Protects listed species from human harm
Third provision - Prevents the federal government from carrying out any project that jeopardizes a listed species
Fourth provision - The USFWS must prepare a species recovery plan for each listed species.
What type of effect does genetic variation have on a population?
It increases the chances that some members of the population surviving environmental pressures and changes.
Why do humans depend on healthy ecosystems?
To ensure a healthy biosphere that has balanced cycles of energy and nutrients.
What are the four major causes of extinction?
What do reefs provide (4 answers)?
Millions of people with food, tourism revenue, coastal protection, and sources of new chemicals.