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Weeks 1 & 2 - Introduction, Ecosystems, Symbiotic Relationships, and Human Impacts

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Book: Weeks 1 & 2 - Introduction, Ecosystems, Symbiotic Relationships, and Human Impacts
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Date: Thursday, 18 September 2025, 3:16 PM

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Weeks 1 & 2 - Introduction, Ecosystems, Symbiotic Relationships, and Human Impacts

Table of contents

1. Introduction

 Introduction


Introduction: Activity 02 - An Overview of the Module
INTRODUCTION
Have you ever watched the birds fly overhead in the summer and wondered where they came from and where they were going to spend the night? We all wonder about the world around us. For this module, we will ask the questions ecologists ask, but not just about birds.

As ecologists, we will try to understand why all living things live in the places that they do. We will also explore how we as humans interact in the global ecosystem.

In the introduction to this module, "Interactions and Ecosystems", you will complete 2 exercises and a pretest.

Copyright © 2001, the Crown in Right of Alberta, as represented by the Minister of Learning, Alberta Learning, 11160 Jasper Avenue, Edmonton, Alberta T5K 0L2

Picture and Photos:( For specific picture reference view page source.)
Copyright © 2000-2001 www.arttoday.com, Copyright © 2001 Jeannie Charrois, Copyright © The Essentials Clip Art CD, MaGlas-l.gif.

Lesson 1


Introduction: Activity 02 - An Overview of the Module
Discussion
Unlike any other organisms on the Earth, humans have the greatest ability to change their environment. Through the creation of tools, humans have been altering their environment in ways thought to improve life. Do these changes help all those living things in the ecosystem? Past history and current concerns over global warming, acid rain, and the destruction of forests would suggest that this is not always so! What we do in the name of "progress" is often more destructive to the global environment.

In recent years, the impact of humans has caused a number of dramatic changes to a variety of ecosystems found on the Earth. Humans use and modify natural ecosystems through agriculture, forestry, recreation, urbanization, and industry. The most obvious impact of humans on ecosystems is the loss of biodiversity. If we understand our interactions with the environment, we can take steps to keep the Earth a fit place for all organisms to live. We all have an impact on the environment. Think about how you are affecting your environment.

Picture and Photos:( For specific picture reference view page source.)
Copyright © 2000-2001 www.arttoday.com, Copyright © 2001 Jeannie Charrois, Copyright © The Essentials Clip Art CD, MaGlas-l.gif.Copyright © 2001, the Crown in Right of Alberta, as represented by the Minister of Learning, Alberta Learning, 11160 Jasper Avenue, Edmonton, Alberta T5K 0L2

 Lesson 1


Activity 03 - LESSON 1: Defining an Ecosystem and Learning about Basic Needs
ACTIVITY A: Ecosystems


Textbook Readings

Science in Action 7
page 11
or
Science Focus 7
page 13

Living things cannot exist on their own. Every living thing must interact with its environment in order to survive. Organisms continually interact with their environment by creating or taking in energy in the form of food and releasing waste materials which are recycled by the ecosystem. As energy can neither be created nor destroyed, energy in the ecosystem is moved around through the ability of living things to consume others or to be consumed themselves.

An ecosystem can be compared to a huge factory with many moving parts, producing many different products. This environment will function the best when all the supplies are in balance - when organisms, materials, and energy interact together in a single system. However, when a part of the factory breaks down, or the supplies that make the products run out, the effects are felt throughout the factory. In the same way, when our ecosystem is altered, the effects are felt not only by the organism which caused the change, but by all those organisms which rely on that part of the ecosystem.

The Earth contains many ecosystems. Each of the ecosystems can be divided into smaller communities and populations. Living in each of these smaller categories are individual species. Think about the meaning of each of these highlighted words as you complete the activity below.



KeTextbook Readings

Science in Action 7
page 8 and 10
or
Science Focus 7
page 38

ACTIVITY B: Biotic and Abiotic Factors

Why is it that you cannot hold your breath forever? After only a minute or so you feel like your lungs will burst and you need to take a breath. As a member of the animal kingdom you need oxygen in order to survive. Oxygen is a non-living or abiotic component of life on Earth.

One way to take a closer look at an ecosystem is to divide the environment into living and non-living parts. The terms we use to describe these components are biotic and abiotic. Biotic is used to describe living things such as plants, animals and micro-organisms. Abiotic is the term given to describe the parts of the environment which are non-living. This would include things such as oxygen, sunlight, water, soil, temperature, wind speed, and the contours of the land. All these factors affect how organisms must function and adapt to their environments in order to survive.

By examining your current surroundings, you already know many of the ways in which different parts of the environment interact. If you go outside and find an ant eating a leaf, you would say this is two biotic factors interacting- the ant and the leaf. If you are looking at a plant growing in a sunny window you are viewing the process of photosynthesis. Photosynthesis is an interaction between a biotic component (the green plant) and many abiotic components (sunlight, water, and carbon dioxide). Through this interaction, the plant is able to produce its own food and give off an abiotic product called oxygen. An area's ecosystem is the network of all the biotic and abiotic components and the relationship between them.
HOW DO I KNOW IT IS ALIVE(BIOTIC)?
We often wonder if something is really living, non-living, or dead. If something is considered to be living it will have all of the characteristics list below. Don't be fooled-many non-living things may appear to have characteristics of living things, but if something does not have all the characteristics, it is not considered to be biotic or alive.
1. All organisms grow. Just like you will grow to approximately the same size and shape as your parents, all other living things grow to resemble the adults in their species as well.
2. All organisms move. An animal's movement from place to place can be obvious. Movement by other organisms may appear to be less obvious, but a plant's growth towards the sunlight, or small movements such as breathing, are evidence that an organism is alive.
3. All organisms reproduce. By reproducing organisms ensure their species will continue to survive. Organisms use a variety of ways to reproduce.
4. All organisms produce or take in food. All living things need energy to remain living. Animals receive their energy from food which they eat. Animals must eat other living things to get food. Plants are able to produce their own food through the process of photosynthesis. They use the Sun's energy to make food from carbon dioxide and water.
5. All organisms respond to stimuli in their environment. Organisms have the ability to react to a stimulus. A tulip which opens its petals on a sunny day or a dog who comes when called are responding to stimulus
6. All organisms are made up of cells. If you had a microscope and you looked at a living organism under it, you would see that all living things are made up of tiny units called cells. Even those things which were once living and are now dead will still be made up of cells. When we say something is "dead", we mean it once had life. Cork comes from Oak trees. If you were to look closely at a cork from a bottle, you would still be able to see where the cells used to be, even though the wood is now considered to be dead.
7. All organisms have a common chemical make-up. The shape of the organism does not matter. All organisms are made up of the same chemicals-carbon, hydrogen, nitrogen, and oxygen. Many organisms may contain additional chemicals, but these four chemicals are common to all living things.

Exercise 1.1: Biotic/Abiotic/Dead



ACTIVITY C: Basic Needs and Range of Tolerance

Imagine you have become a castaway on a deserted island in the South Pacific. When you wash up on shore there is no one else there with you. You are wearing little more than a t-shirt and jeans. All your luggage has been lost. The island has abundant vegetation and there are birds singing in the trees. The ocean water surrounding the island appears to be teeming with life.

Once you realize you are alone on a deserted island you panic! You now must put some of your science training to action if you are going to survive. You remember that all living things have a few basic needs. Do you remember what these are?
Textbook Readings

Science in Action 7
page 12 to 14
or
Science Focus 7
page 6 to 8

While you are gone, your neighbourhood friend, Cindy, has offered to look after your plant collection which consisted of tropical plants, ferns, and a cactus. Cindy wants to make sure the plants are healthy and decides to make sure they are well watered. When you finally return, you find your favourite cactus is rotting and dying. What could have caused this? Tropical plants and ferns thrive in a shady and moist environment. Cacti have adapted to grow best in warm, sunny, and dry environments. When Cindy watered the plants, she over-watered the cactus causing the cactus to die.
In the wild, most species appear to be limited in at least part of their geographic range by abiotic factors such as temperature, moisture availability and soil nutrients. For example, a plant may die if the temperature drops below 0° C or goes above 40°C. The range within which an organism can survive is called the organism's range of tolerance. No species has adapted to survive under all conditions found on the Earth. All species have specific limits of tolerance to physical factors that directly affect their survival or reproductive success. An abiotic factor's range of variation in which a species can survive and function is commonly defined as the range of tolerance. The level within the range of tolerance at which a species or population can function most efficiently is termed the optimum.
Copyright © 2001, the Crown in Right of Alberta, as represented by the Minister of Learning, Alberta Learning, 11160 Jasper Avenue, Edmonton, Alberta T5K 0L2

Picture and Photos:( For specific picture reference view page source.)
Copyright © 2000-2001 www.arttoday.com, Copyright © 2001 Jeannie Charrois, Copyright © The Essentials Clip Art CD, MaGlas-l.gif.

2. Interactions Among Living Things

Lesson 2


Introduction: Activity 02 - An Overview of the Module

Ducks Unlimited Movie
What use is a swamp, marsh, or bog?

It is normal for human beings to often see little value in land that contains a swamp, marsh, or bog. Often when people look at a wetland they see an area that can not be used and profited from. It is not like a nice lake beach that can be used by sunbathers and swimmers alike. Is this reason enough to remove these wetlands?

To many species wetlands are vibrant ecosystem and a place to raise their young and protect their families from predators.

Ducks Unlimited, a national nonprofit conservation organization, has been working to preserve, enhance, and restore many wetlands throughout Canada. Wetlands are valuable ecosystems. In the past, their value has not been understood. They have been drained, filled, and transformed into agricultural land for farmer and industry . When humans are making decisions about economic progress, often the environment is sacrificed to make way for the progress of mankind. Ducks Unlimited is working to create a balance between human and wetland needs.

Watch the accompanying Quicktime Video called "If You Build it..."by clicking the movie projector icon below.

Copyright © 2001, the Crown in Right of Alberta, as represented by the Minister of Learning, Alberta Learning, 11160 Jasper Avenue, Edmonton, Alberta T5K 0L2

Picture and Photos:( For specific picture reference view page source.)
Copyright © 2000-2001 www.arttoday.com, Copyright © 2001 Jeannie Charrois, Copyright © The Essentials Clip Art CD, MaGlas-l.gif.

Lesson 2


Activity 03 - LESSON 2: Interactions Among Living Things
ACTIVITY A: Symbiotic Relationships
Now that we understand that each organism interacts with abiotic elements around them, we will look at the type of relationships which can form between species. Symbiosis is a relationship between two different species. Some of these symbiotic relationships provide mutual benefit to both organisms, some may only benefit one, and others may lead to the death of one of the organisms.
COMMENSALISM
"Hitchhiker" is the best word used to describe a species which benefits from this kind of relationship. In commensal relationships, one species benefits and the other neither benefits nor is harmed. Often the host species provides a home and/or transportation for the other species.
Barnacles hitchhike on the backs of whales, but the whale does not benefit or suffer from this relationship. In the tropics, clownfish can live safely among the stinging thread tentacles of sea anemones. These threads provide protection from predators, yet have no effect on the clownfish. The clownfish feed on the leftover food from the sea anemone, but the sea anemone appears to receive nothing in return.
MUTUALISM
Flowering plants and bees interact in a mutualistic fashion. The bees fly from plant to plant collecting nectar for food and in the process will also pick up pollen as its body rubs up against the flower. As it moves from flower to flower it transfers the pollen and the plants benefit by being able to reproduce. This is a "garden" example of mutualism .
Colourful, crusty lichen grows on rocks in the Arctic Tundra of Canada. What is lichen, a plant or a fungus? Both! Lichen is formed by the union of a fungus and an algae. The fungus give the algae a place to live, as well as water and nutrients. The algae provides food to the fungus through the process of photosynthesis. They survive because of this mutual relationship. Without it, they would never make it on their own.
PARASITISM
"You say you saw a white moose in Elk Island National Park?"

"Moose are not white!"

"They can be if they scratch away all their protective outer hair."

In the spring, if the temperature is warmer and drier than usual, an explosion of blood sucking ticks can form. If these parasitic ticks decide to make a moose their host, the moose will be irritated by the itching and attempt to scratch at the problem by rubbing up against trees. This causes the protective coating of black hair to be removed. If spring temperatures drop, moose can then die from hypothermia.
Parasitism is the darker side of symbiosis. In these relationships, the parasite benefits, while the host is harmed. In most cases the parasite is not out to kill its host, because if the host dies, so does the food source for the parasite, which will ultimately bring about its own death. Parasitism will often make the host sick or uncomfortable. These factors may lead to death indirectly.

Textbook Readings

Science in Action 7
pages 16 to 17
or
Science Focus 7
pages 14 to 16


ACTIVITY B: Niche, Competition, and Adaptation
A niche is the term used to describe the roles or functions an organism plays in a community. Every type of organism has its own niche. No two species have the same identical role in a community.
Imagine what might happen in your home if you did not play your roles. Let's say, it is your job to take out the garbage and buy all the groceries. If you stopped doing your job, what would happen? I know you think your mother or your brother would just do it for you, but what if they did not know how to perform these jobs? The garbage would pile up and the food would run out. Members of your family would be greatly impacted by the jobs you are not doing. This would lead to one of three things occurring within your home:
  • Your family may adapt and fill the niche you vacated.
  • Your family may adapts and then exclude you from the family.
  • Your family may suffer due to a lack of food or sickness cause by rotting garbage.
The above example may seem harsh, but this is what happens in natural communities. Each species plays a particular part in the ecosystem it shares with other organisms. Some species are producers, while others are consumers or decomposers. The ecological niche includes both the animal's or plant's physical habitat and how it is adapted to life in that habitat. In examining its adaptive strategy, ecologists consider how the plant or animal obtains its energy in order to live. Each organism has many adaptations to its habitat. The first adaptation concerns where in the habitat the animal or plant has chosen to live.
COMPETITION FOR A NICHE
Competition plays a large role in the ecosystem. Every plant and animal competes with other organisms to survive. If two species attempt to occupy the same niche in a community, competition will lead to one of three possible outcomes: extinction, exclusion, or character displacement adaptation.

Extinction of a species from a certain habitat is likely when two species want to fill the same niche in the community. This happens every year when you put in your garden. Prior to any of your plant sprouting, weeds are well on their way.
If they are left untouched, weeds will tend to grow faster and bigger than the other plants in the garden, crowding out, blocking sunlight, and taking valuable water and nutrients from the soil. Vegetables in this garden have to compete at a disadvantage and often do not produce plentiful crops or become extinct from this habitat. This is why your mother always sends you out to the garden to pick the weeds.
The coyote and the red fox have similar roles in their habitat, but when the two attempt to live in the same community, competition leads to exculsion. In Alberta, the coyote lives in the grasslands, and the red fox inhabits the forest edge and meadow areas. When humans cut more into the forested areas to create farmland, the red fox looses more of its habitat to the coyote. In some places, the coyote has pushed the red fox out of its part of the habitat.
Character displacement adaptation is the final possibility when organisms compete for the same niche. When two species compete for the same niche, they develop differently than they would if they did not co-exist. There is an island ecological reserve for birds off the coast of Newfoundland. This reserve is made up of small islands which find themselves to be the home of numerous species of birds. For these birds to co-exist they can not be in constant competition for nesting areas and food. For two species to exist in this habitat one of the species and perhaps both may need to modify their niche. For example, if both birds are accustomed to making their homes in the cliff of the rock, one will have to adapt and make their nests on the grassy shoreline, or burrow into the brush.

Textbook Readings

Science in Action 7
page 19
or
Science Focus 7
pages 10 to 11 and 40 to 41

 

ACTIVITY C: Adaptation Investigation
Look at all the birds on the left. What do you think they eat? Fish, insects, mice, could be some of their favourite meals. Their beaks might give you a clue about their diet as their beaks are crucial in helping the bird catch and eats its prey.
Now, what if a bird's normal diet was in short supply and they had to look for other sources of food? Would they be able to adapt to different food sources? Would they survive? Well this is what we are going to investigate today in your home lab.

QUESTION

Can birds switch to a different types of food if their regular food is in short supply?

HYPOTHESIS

Form a hypothesis about whether birds will be able to survive if their usual food supply is restricted. Remember; your hypothesis should state your answer to the question as well as your reasons for that answer.

MATERIALS REQUIRED

toothpick
kitchen tongs
clothespin
teaspoon
cup
clock or watch
pencil or pen
paper
raisins-10 pieces
rice- 10 grains
cereal such as Cheerios, fruit loops, or puffed wheat-10 pieces
elastic bands- 10 pieces
macaroni, uncooked-10 pieces
PROCEDURE
You may choose to substitute an apparatus or food item if you are missing any of the items on the materials list. Make sure to note the change in your observations. 1. On a table, lay out the rice, cereal, elastic bands, raisins, and macaroni in small scattered piles of 10. You should have 5 piles one for each of the food items which the birds like to eat.
2. Starting with the toothpick you will try to pick up as many raisins using only the toothpick in 30 seconds. As you pick up the raisins, one at a time, they must be deposited into the cup. The cup represents the stomach of the bird.
3. Once the first 30 seconds has elapsed, move to the second pile of food, the rice, and see how many of these items you can pick up one at a time with the toothpick and deposit in the cup. Once again you only have 30 seconds for each food pile.
4. Continue the steps above for the remaining 3 food sources.
5. Once you have attempted all 5 food piles with the toothpick, count each of the food items placed in the cup and record the number into your observations data chart in your word processing document.
6. Repeat the steps above for the remaining beaks-kitchen tongs, clothespin, and spoon.

Exercise 1.2: Adaptation Investigation

3. Lab Preparation

Lesson 3


Introduction: Activity 02 - Lesson 3 Lab Preparation


OPTIONAL ACTIVITY - Observing the Recycling of Nutrients

You will complete this lab later in the module. In order to make sure you will have something to observe you must gather the materials and follow the procedures at this point. You can make your observations over the next couple of weeks. When you reach Lesson 3 you should have all your observations completed and at that time you will have to do some analysis on your data.


OBJECTIVE
Observing nutrient recycling.

MATERIALS REQUIRED

  • Two clear plastic or glass containers like mayonnaise jars or large peanut butter jars
  • Sand. Enough to fill each jar at least 1/3 from the bottom. It does not need to be perfectly clean.
  • Table scraps.
  • Worms and beetles from the garden (optional)
  • Two small plants or seeds.
PROCEDURE
Part 1: 1. Fill one jar approximately 1/3 full of sand.

2. Collect table scraps over a few days. Potato peals, apple cores etc. Place them in the jar with the sand. Mix them in with the top layer of sand.

3. You may add some worms and beetles from the garden if it is the right season.
4. Sprinkle a little water on it each day. (Do not add too much water)
5. Observe over at least one week.
6. Record your observations.
Part 2: 1. After the scraps have decomposed. Set up the second jar with sand but no scraps.
2. Place a small 4 inch plant in each jar (or a seed)

3. Sprinkle a little water each day.
4. Observe the plant growth.
Copyright © 2001, the Crown in Right of Alberta, as represented by the Minister of Learning, Alberta Learning, 11160 Jasper Avenue, Edmonton, Alberta T5K 0L2

Picture and Photos:( For specific picture reference view page source.)
Copyright © 2000-2001 www.arttoday.com, Copyright © 2001 Jeannie Charrois, Copyright © The Essentials Clip Art CD, MaGlas-l.gif, Copyright © 2001, The Object Series 10, Copyright © 2001 Shauna Burke

 

Lesson 3


Activity 03 - LESSON 3: Human Impacts on the Ecosystem
ACTIVITY A: Human Impacts Over Time
Humans have a history that goes back thousands of years, yet for the most part, our previous ancestors have left only very small traces of their existence. Like us, they required the basic necessities of life - water, food, clothing, shelter. But the amount of waste they created, that was not easily recycled back into the environment, appears to be so small archeologists have a difficult time studying the past. What is different about the materials they used then to the materials we use now?

A little more that a century ago, the population of Edmonton was only 600. At that time there was no need for garbage collection. Nothing of value was thrown away. What could not be re-used, traded, or repaired, was burned as a source of heat for the homes.

As the population and pace of life in Edmonton grew, so did the mounds of household waste, yard refuse, manure, and ashes. In 1892, the first town scavenger was appointed and paid $1.00 a load to collect and haul garbage to the nuisance grounds.
As our lifestyles have changed and the number of people in the area has increased the production of waste has also increased. Each Alberta household produces an average of 800 kilograms of nonrecyclable waste each year. This is more than double the amount of garbage that was produced per household only a century ago. In the past few decades all this waste was simply buried in dumps and city landfills.
Now that the population of Edmonton and surrounding areas is fast approaching 1 million, the management of waste has become serious business. No one wants to have a landfill site created in their neighbourhood, so other means of waste management had to be created. Why has the amount of garbage per household increased over the last century? What inventions or changes in lifestyle have lead to more garbage?

Textbook Readings

Science in Action 7
pages 20 to 23
or
Science Focus 7
page 18 to 23

 Exercise 1.3: Human Impacts Over Time

Watch the movie below, "Dealing with waste in the 21st century" then click on the icon to answer the questions.

 

4. Human Impacts on the Ecosystem

Lesson 4


Activity 03 - LESSON 3: Human Impacts on the Ecosystem

ACTIVITY A: What You and Your Community Can Do!
Now that you have turned Dumptown into Recycle City it is time to look at how everyone is doing their part to keep human impact on the environment as low as possible.
Welcome to this Virtual Scavenger Hunt! Scattered throughout Recycle City, you'll find all the answers and information you need to answer the questions below. I hope this will also give you more ideas about how to reduce, reuse and recycle in your own home and community.

Answer the questions below and begin the Scavenger hunt in Recycle City!

Exercise 1.4: Recycle City

 
ACTIVITY B: Alberta Recycling & Composting

Alberta is a leader in North America for managing waste. The Edmonton Waste Management Centre at Clover Bar includes the largest co-composter in North America. Waste that could not be recycled was traditionally buried in landfills. In the year 2000, Edmonton began a new era of waste management. Now, 15 to 18% of household waste is recycled in the blue bag program, and all the remaining household solid waste is taken to the new composting facility.

About 65% of all household waste is organic. As it is organic, it can be combined with biosolids (sewage sludge) and processed back into compost.

Also in Alberta, the Alberta Beverage Container Recycling Corporation works with beverage companies to recycle the containers used to package beverages. Find out how many containers are recycled by watching the video "Recycling makes Sense- Beverage Container Recycling in Alberta."

5. Unit 1 Interactions and Ecosystems Section 1 Notes

Section 1 Notes

6. Unit 1 Section 1 Quiz

You will have two opportunities to write this section quiz. This quiz consists of 10 questions. Use the results from your 1st attempt to help you prepare for your second attempt. Your best score will be taken as your assessment mark. You have 10 minutes to complete this multiple choice quiz. Remember to do this quiz under testing conditions without texts, aids, or help.

Click the icon to go to the quiz.