1. Interactions of Living Things

2. Ecology
Ecology is the study of interactions that occur among organisms and their environment.

3. Ecosystem
An ecosystem is all the organisms living in an area and the nonliving parts of their environment.

4. Abiotic Factors
Living or once-living environmental features are called biotic factors.
Animals
Plants
Abiotic factors are
nonliving physical
features.

5. Abiotic Factors Atmosphere-the air that surrounds Earth
Water-the major ingredient of the fluid inside the cells of all organisms.

6. Abiotic Factors
Soil-a mixture of mineral and rock particles, the remains of dead organisms, water, and air.
Sunlight-the source of energy for most life on Earth.

7. Abiotic Factors Temperature
Most organisms’ body temperatures should stay within the range of 0 ̊C to 50 ̊C for survival.
Temperature is affected by latitude; areas closer to the equator are warmer than areas farther from the equator.
Elevation-distance above
sea level that affects
temperature, wind and soil.

8. Abiotic Factors
Climate-an area’s average weather conditions over time, including temperature, precipitation, and wind.
For most living things, temperature and precipitation are the two most important components of climate.
Heat energy from the
Sun creates air
currents
called wind.

9. Discussion Question
What abiotic factor supplies energy for most life?

10. Biotic Factors
A population is made up of all the organisms in an ecosystem that belong to the same species.
A community is all the populations in an ecosystem.

11. Biomes Factors that affect biomes climate:
Temperature
Precipitation
Major biomes-large areas with similar climates and ecosystems.

12. Tundra Cold, dry, treeless region
Permanently frozen soil called permafrost
Average winter temperature: -12 °C
Average precipitation is less than 25 cm per year.
Plants: mosses, grasses, small shrubs, lichens
Animals: insects, ducks, geese, other birds, mice, arctic hares, reindeer

13. Taiga Cold forest of mostly evergreen trees.
Soil thaws in the short summer
Precipitation: mostly snow, 35 cm-100 cm per year.

14. Temperate Deciduous Forest
Region with four seasons, mostly trees that lose their leaves in autumn.
Temperature range from below freezing in winter to 30°C or more in summer.
Precipitation: throughout the year, 75 cm -150 cm per year.

15. Tropical rain forests The most biologically diverse of all biomes
Average temperature: 25°C
Precipitation: 200 cm – 600 cm per year.
Four zones: forest floor, understory, canopy, emergents
Human impact: Habitats being destroyed by farmers and loggers.

16. Desert Driest biome, supports little plant life.
Temperatures: vary from hot to cold.
Precipitation: less than 25 cm per year.
Soil: thin, sandy, or gravelly
Plant: cactus
Animal: kangaroo rat

17. Grasslands Prairies or plains, dominated by grasses
Temperatures: temperate or tropical
Precipitation: 25 cm – 75 cm per year; dry season.

18. Discussion Question
What temperature ranges and precipitation levels support the greatest diversity of plants and animals?

19. Aquatic Ecosystems Rivers Streams Lakes Ponds
Freshwater ecosystems- include flowing and standing water, low or no salt.
Rivers
Streams
Lakes
Ponds

20. Wetlands Regions wet all or most of year
Lie between solid land and water
Very fertile ecosystems

21. Salt water ecosystems
95% of Earth’s water contains high concentration of salt, or high salinity.

22. Open oceans Divided into lighted and dark life zones
Lighted-upper 200 m and home of plankton
Dark-below 200 m where animal feed on material that floats down or prey on each other.

23. Coral reefs
Diverse and fragile ecosystems formed from coral shells of calcium carbonate

24. Seashores Along coastlines
Intertidal zone- covered with water at high tide and exposed to air at low tide.
Drastic changes in temperature, moisture, salinity, and wave action.

25. Estuaries
Where a river meets an ocean; called bays, lagoons, harbors, inlets, sounds.
Rich in nutrients
Changing mixture of salt water and freshwater.

26. Discussion Question
What is the general relationship between sunlight and aquatic life?