1. Interactions of Living Things
The Environment

2. Ecology
All organism, from the smallest bacteria to a blue whale, interact with their environment
Ecology: the study of the interactions among organisms and their environment
Abiotic factors: nonliving parts of the environment
Biotic factors: living or once-living organisms in the environment

3. Abiotic Factors
Examples of abiotic factors: water, sunlight, temperature, air, and soil
These factors are important in determining which organisms are able to live in a particular environment

4. Ecologist study biotic and abiotic factors in an environment and the relationship among them. Many times, ecologists must travel to specific environments to examine the organisms that live there.
                                                                                                                                       

5. Water All living things need water to survive
The bodies of most organisms are 50 – 95% water
More than 95% of Earth’s surface water is found in the oceans
Saltwater environment in the oceans is home to a vast number of species
Freshwater environments support thousands of types of organisms

6. Saltwater accounts for 97% of the water on Earth
Saltwater accounts for 97% of the water on Earth. It is found in the seas and oceans.
Only 3% of Earth’s water in freshwater

7. Light Light and temperature affect the environment
The availability of sunlight is a major factor in determining where green plants live
Algae live near the water’s surface where sunlight can penetrate
Little sunlight reaches the forest floor, so very few plants grow close to the forest floor

8. Flowers that grow on the forest floor grow during the spring when they receive the most sunlight.

9. Temperature
Temperature can determine which plants and animals can live in a region
Some areas of the world have a fairly consistent temp. year round, but others vary
Water environments throughout the world also have a widely varied temp.
Plant and animal species found in the freezing cold Arctic, in the extremely hot water, and every temp. in betwee,

10. Air
Although you can’t see the air that surrounds you, it has an impact on the lives of most species
Composed of a mixture of gases
Polluted air can cause the species in an area to change, move, or die off
All species are affected by the weather in the area that they live

11. Air pollution can come from many different sources
Air pollution can come from many different sources. Air quality in an area affects the health and survival of the species that live there.

12. Soil From one environment to another, soil can vary greatly
Soil type is determined by the amounts of sand, silt, and clay it contains
Different plants need different kinds of soil
Soil affects every organism in an environment

13. Soil provides a home for many species of animal.

14. Biotic Factors
Abiotic factors do not provide everything an organism needs for survival
Organisms depend on other organisms for food, shelter, protection, and reproduction
How organisms interact with one another and with abiotic factors can be described in an organized way

15. Levels of Organization
The living world is highly organized
Atoms – molecules – cells – tissues – organs – organ systems – organisms
Biotic and abiotic factors also can be arranged into levels of biological organization
Organism – population – community – ecosystem – biome – biosphere

16. Organism: An organism is one individual from a population.

17. Populations
All the members of one species that live together make up a population
EX. All of the catfish living in a lake at the same time make up a population
Members of a population compete for food, water, mates, and space
The resources of the environment and the ways the organisms use these resources determine how large a population can become

18. Population: All of the individuals of one species that live in the same area at the same time make up a population

19. Communities Most populations of organisms do not live alone
They live and interact with populations of other types of organisms
Groups of populations that interact with each other in a given area form a community
Populations of organisms in a community depend on each other for food, shelter, and other needs

20. Community: The populations of different species that interact in some way are called a community.

21. Ecosystem
Ecosystem is made up of a biotic community and the abiotic factors that affect it
Ex. Coral reefs, forests, and ponds

22. Ecosystem: All of the communities in an area and the abiotic factors that affect them make up an ecosystem.

23. Biomes Scientist divide Earth into different regions called biomes
A biome is a large region with plant and animal groups that are well adapted to the soil and climate of the region
Many different ecosystems are found in a biome

24. Biome: a biome is a large region with plants and animals well adapted to the soil and climate of the region.

25. This map shows some of the major biomes of the world
This map shows some of the major biomes of the world. What biome do you live in?

26. Biosphere The part of Earth that supports life is the biosphere
Includes the top part of Earth’s crust, all the waters that cover Earth’s surface, the surrounding atmosphere, and all biomes
The biosphere is only a small part of Earth

27. Biosphere: The level of biological organization that is made up of all the ecosystems on Earth is the biosphere.

28. Quiz What is an ecosystem?
How are the terms ecology and environment related?
Explain how biotic factors change in an ecosystem that has flooded.

29. Answers
All of the communities in an area and the abiotic factors that affect them
Ecology is the study of the interactions among organisms and their environment
Organisms that do no live in water would die. Other water organisms might move into the ecosystem