BioGT ch34: The Biosphere- Flashcards

34.1

• Ecology: The scientific study of the interactions of organisms with their environment

• Environmental factors

  • Biotic: Organisms in the environment, living component.

  • Abiotic: Nonliving component, physical and chemical

• Habitat: Biotic and abiotic factors creating a specific environment.

• Biosphere: all of earth inhabited by life

  • Landscape: An array of ecosystems

  • Community: group of different living organisms

  • Population: Group of the same organism

  • Organism: single living thing

Our actions have consequences for the entire biosphere

34.2

• Human activities —> environmental consequences

• Ex.

  • DDT was a common chemicals pesticide in the 1950’s

  • DDT also had harmful effects on food, dairy, wildlife, humans, soil, and water.

  • Ecologists fought against these types of insecticides

• Ecologists help people understand the consequences of their actions on the biosphere, such as using harmful chemicals.

34.3

• Organisms must adapt to abiotic factors

• Energy sources

  • All organisms require a source of energy to live

  • Photosynthesis

    • Solar energy powers most ecosystems from plants, which produce their own energy through the process of photosynthesis.

    • Photosynthesis mostly occurs near the surface in aquatic environments

  • Other energy sources:

    • In caves, bacteria take energy from inorganic chemicals to power the ecosystem.

• Temperature

  • Temperature effects metabolism

    • Most species must live in moderate temperatures to keep a working metabolism

  • Animals living in more extreme temperatures must adapt to stay alive.

• Water

  • Just as essential to life as energy

  • Organisms must adapt to avoid dehydration

• Inorganic Nutrients

  • Relied on by photosynthetic organisms

  • Nitrogen, phosphorus

    • Plants obtain these from the soil

  • Low levels can harm aquatic ecosystems is algae and plankton can’t grow

• Aquatic factors

  • Salinity

  • Currents

  • Tides

  • Oxygen

• Terrestrial factors

  • Wind

  • Fire

34.4

Organisms adapt by natural selection

• Example: pronghorn

  • North American species, related to African Antelope

  • Individuals who were able to survive in dry and windy habitats passed down alleles (genetics)

    • Evolved to have hollow hairs that trap heat in the winter

  • Evolved to more efficiently exploit food sources

  • Developed speed to flee from predators

Adaptions from natural selection still benefits animals such as the pronghorn today

• If the environment were to change, these adaptations would no longer be a benefit and natural selection would limit the distribution of these organisms.

34.5

Climate is a crucial part of deciding where a community of organisms lives

• Climate patterns happen due to an uneven distribution of sunlight

  • Angle of sunlight is more direct on the equation and therefore more concentrated

  • Because the earth is round, the same amount of sunlight is distributed over less space near the poles, causing a change in climate

• Trade winds

  • Warm air rises in equatorial areas, is heated and releases moisture (precipitation), then moves away from the equator until cooling.

• Prevailing winds

  • Result from rising and falling of air and earth’s rotation

• Biomes

  • Major types of ecological associations that occupy broads regions

Climate, wind, temperature, and other abiotic factors control the distribution of organisms by biomes.