Download Sci7U1Ecosystems2003

Science 7
Text: Discovering Science 7
Unit One:
Interaction Within Ecosystems
Chapter 1, “An ecosystems is all the living and
non-living things in a particular place.”
Organisms – living things within an ecosystems.
Ex. Worm, tree, whale, bird, dog,…
Adaptations – inherited characteristics which help
an organism to survive. Ex. Webbed feet, feathers,
scales, claws, …
Habitat – the particular place where an organism
lives. Ex. Pond, tree, field, soil, rotting log, …
Types of Ecosystems in
Atlantic Canada
• Coastlines and Oceans
• Freshwater Ecosystems:
(Rivers and Ponds)
• Arctic
• Forest
* Organisms survive in their ecosystems according to
their “range of tolerance.”
Abiotic Parts of an Ecosystem
•
•
•
•
•
Light and Light Intensity
Temperature
Soil
Air and Wind
Water
Biotic Parts of An Ecosystems
•
•
•
•
•
•
•
•
•
•
Virus
Bacteria
Algae
Mammals
Reptiles
Amphibians
Marsupials
Raptors
Crustaceans
Plants
Levels of Organization
•
•
•
•
Individual – one
Populations – many individuals
Community – interactions of many species
Ecosystems – interactions of living and non-living things
Each species in a community has a specific role to place. These
roles make up an ecological niche, which includes where it
lives, how it obtains it’s food, and how it affects its
environment.
Chapter 2, “Living and non-living things interact
in ecosystems.”
Types of Interactions:
Symbiosis
• Parasitism – One organism benefits (parasite) and
the other is harmed (host).
* Internal parasites. Ex. Tapeworm
* External parasites. Ex. Tick
• Mutualism – Both partners benefits. Ex. Lichen
(Alga and fungus).
• Commensalism – One organism benefits and the
other neither benefits or is harmed. Ex. Clownfish
and anemone; whales and barnacles.
Roles of Organisms in the Ecosystem
• Herbivores – Plant eating. Ex. Moose, Rabbit,…
• Carnivores – Meat Eating. Ex. Owl, Spider, …
• Omnivores – Plant and meat eating. Ex. Bear,
mouse, …
Roles of Organisms in the Ecosystem
• Consumers – Organisms that get their food from
the biotic environment by eating (consuming) other
organisms. Ex. Fox eats mouse, shark eat small fish, …
• Producers - Organisms that produce their own food.
Ex. Plants
• Decomposers Scavengers – organisms that live
off the dead, decaying or waste matter of other
organisms. Ex. Vulture, bacteria, fungus, …
Keeping Food from Rotting
Preserving food – Preventing the Growth of Micro-Organisms
•
•
•
•
•
•
•
•
Salting
Smoking
Pickling
Freezing
Vacuum packing
Canning and Bottling
Chemical Additives
Drying
The Food Chain
Food Web
Nutrient Cycle
Chapter 3, “Natural events and human
activities cause changes in ecosystems.”
Succession
• The process by which a biological community
changes over time. Pioneer Species and Climax
Community
The Impact of People on Ecosystem
• Changing Ecosystem – Deforestation, over-fishing,
land fill sites, oil spills, mining, acid rain, Farming
pesticide/herbicides and monoculture…
• Habitat Loss – Urbanization (city building)
• Endangered and Extinct Species
• Introduced Species – native species (fox and polar
bear) and introduced species (moose).
Endangered Species
Extinct Species
Atlantic Cod Fishery
Causes of the Fishery Decline
• New fishing technology made it easier to find
and catch fish.
• More demand for fish from the world market.
• Lack of conservation by governments.
• Unsustainable harvesting – catching too much
fish.
** Sustainable vs. Unsustainable
Fishing technology and Innovation
Monitoring and Managing Ecosystems
• Environmental monitoring helps detect and predict
changes in the habitats of organisms. Environmental
impact assessments using data/information collected
through short term and long term monitoring can be
used to make appropriate decisions to ”prevent”
the destruction of habitats and “protect” the lives
of wild species.
• Baseline Data
• Permanent Plots
Unit One
Summary Review – pages 96 - 97
• Students must realize that the textbook is the
main source of information, especially when
preparing for an end of unit test.
• Worksheets, Guide Notes, PowerPoint
Presentations, etc are supplementary to the
textbook.
• Students should be reviewing materials
presented in class on a continuous basis as
part of a regular home study schedule.