Environmental Science - Chapter 11 Flashcards
True or False. High genetic diversity means that almost all of the individuals of a population have the same characteristics.
False
True or False. Large populations have less genetic diversity than small populations.
False
True or False. A species with a low reproductive rate is more likely to become extinct that one with a high reproductive rate.
True
True or False. Ecosystems have not been significantly influenced by people in virtually all parts of the world.
False
True or False. Humans have changed ecosystems more rapidly and extensively in the last 50 years than in any other period.
True
True or False. One of the consequences of selective breeding is the loss of genetic diversity.
True
True or False. Erosion of unvegetated land adjacent to lakes and rivers causes siltation.
True
True or False. Grazing of arid and semiarid land provides little value or food to the people of that area.
True
True or False. Cutting small, as opposed to large, areas of a forest can reduce erosion of the soil by wind and water.
True
True or False. The introduction of exotic species into a freshwater ecosystem generally increases the population of the native species.
False
Elimination of all of the individuals of a species.
extinction
Those species that could become extinct if a critical factor in their environment were changed.
threatened species
Any change in the DNA of an organism
mutation
Term used to describe all of the different types of genes, species, and ecosystems in a particular region.
biodiversity
Forest harvesting method in which patches of trees are clear-cut among patches of timber that are uncut.
Patchwork clear-cutting
Forest harvesting method in which all trees in a large area are cut and removed.
Clear-cutting
Forest harvesting method in which individual high-value trees are removed from the forest, leaving the majority of the forest undisturbed.
Select Harvesting
Set of physical features that conceals and protects animals from the elements or their enemies.
Cover
Process of changing the natural community to encourage the increase in populations of certain desirable species.
Habitat management
Genetic diversity is influenced by…
migration
mutation
sexual reproduction
One of the measure of biodiversity is the number of…
Different species in the area
The International Union for the Conservation of Nature (IUCN)
- forces countries to take steps to protect endangered species
- prevents trade in endangered species
- publishes a list of endangered and threatened species
Protection of biodiversity typically involves…
legal protection by national laws and international agreements and management of the use of species and ecosystems at sustainable levels
A species becomes extinct when…
all individuals of a species are eliminated
Species are more likely to become extinct if they…
have both a low population density and reproductive rate
Biodiversity includes…
- diversity of genes
- diversity of species
- diversity of ecosystems
Characteristics of a species likely to become extinct include…
- low reproductive rate
- small habitat area
- low population density
A situation that would likely have low species diversity is…
a forest being managed for maximum lumber production
Sport hunting seasons are regulated in the fall so that…
surplus animals are taken before the challenges of winter
An individual can help to control the spread of invasive species by…
- becoming informed about the issue
- by not planting exotic species
- not releasing non-native plants, fish, or other animals into water
The use of range land for grazing by domesticated animals (cattle, sheep, goats)…
causes changes in the vegetation because domesticated animals feed differently that native animals
Activities that result in habitat destruction of forest land, grassland, or aquatic habitats include…
- farming
- forestry
- grazing of livestock
- modification of aquatic habitats
