Ecosystems

An ecosystem is a network of interactions (or links) between the living and non-living parts of an environment.

Living Parts – also called Biotic Elements

• Plants

• Animals

• Birds

• Fish

• Insects

• Bacteria

Species – organisms of the same type that can reproduce to create

offspring (e.g., turtle, deer). Population – all the members of one species living in an area (e.g., all the turtles, all the ferns).

Community – all the different populations living in an area (e.g.,

all the deer, fish, frogs, turtles, ferns, water lilies).

Non-Living Parts – also called Abiotic Elements

• Sunlight

• Water (rain, snow)

• Air (wind, clouds)

• Sand, Rocks, Soil

The Needs of Living Things

A habitat is the physical space where an organism lives and where its basic needs for survival are met.

Sunlight

• Plants use sunlight to make their own food (sugar) through photosynthesis.

• Amount of sunlight determines what can grow

• Animals obtain energy indirectly from sunlight as they eat plants, or animals that themselves eat plants.

• Some animals require sunlight to warm their bodies.

Water

• Plants need water to grow and produce food.

• Animals need water to digest food and form body fluids.

• Some organisms need water to live in.

Air

• Humans and other organisms breathe air to obtain oxygen.

• Plants absorb CO2 from the air to help them make food (sugar).

• Plants make oxygen, and without plants, there wouldn’t be

enough oxygen in the air.

Food

• Provides organisms with nutrients, needed for energy and growth.

• Nutrients include: Sugars, Starches, Fats, Proteins, Vitamins, Minerals

Temperature

• Organisms can usually survive within a certain range of temperature.

• Too hot or too cold for a period of time can be dangerous.

Shelter

• Some form of protection or home for an organism.

• e.g., nest, cave, tree, reef