Living Things and the Environment

1
Living Things and the Environment

• Seventh Grade
• Chapter 22-1

2
Ecosystems

• All the living and nonliving things that interact
  in a particular area make up an ecosystem.
• Some examples of ecosystems are mountains,
  oceans, desserts, and forests.

3
Habitats

• A habitat is a specific place in an ecosystem
  where an organism obtains food, water, shelter,
  and other things it needs to live, grow, and
  reproduce.
• A single ecosystem may contain many habitats.

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Habitats cont.

• Some examples of habitats in a forest ecosystem
  are plants growing in the damp soil, bears on the
  forest floor, and birds in nests at the top of a
  tree.
• Organisms live in different habitats because they
  have different requirements for survival

5
Biotic and Abiotic Factors

• The living things of an ecosystem are called
  biotic factors.
• Examples
• - grass, plants, hawks, badgers, worms,
  fungi, and bacteria that all live in the same
  ecosystem

• The nonliving things in an ecosystem are called
  abiotic factors.
• Examples
• - water sunlight, oxygen, temperature, and
  soil.

6
Water

• Water is very important to all organisms.
• The human body is made up of about 65 water.
• Plants and algae use water, along with sunlight
  and carbon dioxide, to make food in a process
  called photosynthesis.

7
Sunlight and Oxygen

• Sunlight is necessary for photosynthesis which is
  important because without plants or algae to
  provide a source of food, few other organisms
  would live.
• Most living things require oxygen to carry out
  their life processes.
• Organisms on land obtain their oxygen from the
  air while fish and other water organisms obtain
  dissolved oxygen from the water.

8
Temperatures and Soil

• Temperatures that are typical of an area
  determine what can live there.
• Some animals alter their environments to overcome
  very hot or very cold temperatures.
• The type of soil in an area influences the kinds
  of plants that can grow there.
• Some organisms make their homes in the soil.

9
Population

• All the members of one species in a particular
  area are referred to as a population.
• Studying the population is hard to do without a
  specified area. Ex. (Charlotte County)

10
Community

• All the different populations that live together
  in an area make up a community.
• In a community the different populations must
  live close enough together to interact with one
  another.
• They interact by using the same resources, such
  as, food and shelter.

11
Levels of Organization

• The smallest unit of organization is a single
  organism, which belongs to a population of other
  members of its species.
• The population belongs to a community of
  different species.
• The community and abiotic factors together form
  an ecosystem.

12
Ecology

• The study of how living things interact with one
  another and with their environment is called
  ecology.
• Ecologists study how organisms react to changes
  in their environment.