Ecosystems: Flow of Energy and Matter –Name_
Go here for Resources for identifying your plants or animals
Here is a progress test - go to the year 9 test pages
| Key Concept
- 1. Systems
- 2. Patterns, order and organization
- 3. Form and function
- 4. Stability and change
Regular homework tasks – as determined by individual teachers
| Suggested Priority and Timeline
| Suggested Activities
|Extension and Variation
|5.1 Systems: Ecosystems
- o Living Together
- o How Do You Get Your Food?
5.7 Sustainable Ecosystems
- o Energy Flows Through Ecosystem
- o Food Chains and Webs
- o Ecological Pyramids
- o Population Growth
|Pre-test: Access code: ECOPT
Intro: Melbourne Foxes (handout available – 10 min clip) https://www.youtube.com/watch?v=RcD29yYHvJ8
Quick game: Building food webs:
|eBook Plus: Food Web Interactive Activity
|5.2 Mapping Ecosystems
- o Tolerance
- o How Many and Where?
|Prac: 5.1 Using quadrats – second-hand data
Prac: 5.2 Measuring Abiotic Factors
Prac: 5.3 The Capture-Recapture Method
Prac 5.4 Biotic and Abiotic factors
|eBook Plus: Quadrant Method Interactive Activity
9 Ecosystems 1.5 Food Chains Webquest.doc
9 ecosystems 1. Year 9 Field Manual.docx
|5.3 Plant Organisation
- o Plant Cells
- o Parts of the Plants – roots, leaves, stems and flowers
- o Solar Powered
- o Why Are Plants Called Producers?
- o Photosynthesis
- o Why Are Plants Green?
5.5 Cellular Respiration
- o Cells Need Energy
- o Aerobic Respiration (not the three stages)
- o Anaerobic Respiration
|Prac: 5.5 Stem Transport Systems (teacher demo)
Prac: 5.6 Observing Epidermal Cells
Prac 5.7 Looking at chloroplast under the light microscope
Prac 5.9 Out of the light
Prac 5.10 Fermenting Fun
|Create: Story of Water Molecule Movement (p195)
Research: Work of Friedrich Went and Charles Darwin on their work on auxin and plant growth
Analyse: Photosynthesis Brainstorm (p203)
eBook Plus: Deep Sea Creatures
|END OF TOPIC TEST
Revision for Exams
an ecosystem is defined by the biological communities that occur in a specific locale and the physical anchemical abiotic factors as well as the interactions of organisms between each other and the abiotic factors.
Interactions between species
Species is a group of organisms that all have similar structures and characteristics. More importantly members of the same species can reproduce fertile offspring. a type exist in an ecosystem within a specic ecological niche.
The niche of a species includes its habitat (where it lives within the ecosystem), its nutrition (how it obtains its food) and its relationships (interactions with other species within the ecosystem).
Interactions within an ecosystem may be between members of the same species or between members of different species. Examples of types of interactions include competition, predator–prey relationships and symbiotic relationships such as parasitism, mutualism and commensalism.
|Water or moisture
|Soil or water chemistry (e.g., P, NH4+)
|All of these vary over space/time
abiotic factors are those that are not living. They include pH, soil type, wather availability, availability of light and hence topography., availability of gases like, oxygen, carbon dioxide, but also excesses of toxic gases.
biotic factors include the interaction if living things. So it includes predators or relationships between an animal. Or plant.
Energy flow and describing interactions within an ecosystem
Food webs and food chains
A food web is a more realistic and accurate depiction of energy flow. Food webs are networks of feeding interactions among species.
The food pyramid provides a detailed view of energy flow in an ecosystem. The first level consists of the producers (usually plants).All higher levels are consumers. The shorter the food chain the more energy is available to organisms.
It is useful to realise that the energy transfer between trophic levels decreases. Only about 10% of all the energy acquired at a trophic level is passed to the next trophic level.
- Food chain
- food web
- food pyramid - biomass -based on the dry mass of the organisms in the pyramid
- pyramid of numbers - based on the number of organisms required to maintain the organism at the next trophic level
eg algae -------->little fish-------->bigger fish -------> seagull
100% 10% 1% 0.1%
Sampling an ecosystem
Sampling methods are used to determine the density and distribution of various populations and communities within the ecosystem. Transects are very useful when the environmental conditions vary along the sample under investigation. Quadrats can be used to estimate the distribution and abundance of organisms that are stationary or do not move very much. The mark, release and recapture sampling method is used to determine the abundance of mobile species.
1. Transect is where you identify the different species along a straight line through an ecosystem. You then measure the changes in abiotic and biotic factors along this line. You use this information to explain why certain species proliferate in aspecific area along the transect.
2. Quadrats are used to measure / estimate the distribution and abundance of a species of stationary organisms - plants, sessile animals or slow moving animals.
3. Capture REcapture is the techniques we use with animals. This involves first capture organisms of a species and tagging them. You then release them back into their ecosystem. You then capture another set of the same species and record whether r not they are tagged. If most of the animals are tagged this tells you they stay in the same area and there are not many of this species. If hardly any of the animals are tagged this tells you that there are lots of this organism OR this species moves through this ecosystem ( migration)
What can you measure about different species
1. Abundance ... This is how many individuals of a species
2. Population density .... This is how many individuals of a species in a given area. Eg number /metre squared.
3. Distribution..... This is where the individuals of a species are spread out in an area or landscape. When you examine the distribution of a species you tend to find which abiotic factors affect their location. The different abiotic factors can promote the abundance of the individuals or in some cases may reduce the number of the individuals. The same can be said about the biotic factors.
Here is an example with ringtail possums.. The population density of possums in Beaumaris is 1 per 100 m sq. the distribution of possums are concentrated along the Coast in areas that have lots of soft leaf trees and shrubs and some old trees with hollows or houses into which they can gain access to the roof.
from this information we would not expect to find possums on the school oval even though the density is 1 / 100 m sq and the oval is 3000 sq m. According to our population density measurements we should see 30 possums lounging around on the oval!!! But why not?
The possums population distribution is more affected by the biotic and abiotic factors. Obviously the the biotoic factors of food and shelter do not favour the possums lifestyle on the oval. On the other hand we would expect to find some possums in the trees around the school .. Providing they are soft leaf trees and shrubs that are close together so the possums can hide during the day.
Ways of measuring populations of different species
A quadrat is usually a square shaped study area, used to determine the population density (and hence abundance) of an organism. Quadrat sites are either chosen in a random fashion or placed in a series along a grid or a transect line. Using a quadrat is relatively simple; just count the number of species inside it! use the data to then convert your counting to provide the number of organisms of species per square metre. (number /m2)
LINE AND BELT TRANSECTS:
Line transects are taken along a continuous straight line. They can be of any length, but samples are taken at uniform intervals along the length. The transects are best used when the abiotic factors gradually vary, causing a change to the species of organisms living there. Examples include seashores (low to high tide), across streams, up hillsides etc…
A line transect can be used with a quadrant to sample in more detail, otherwise population estimates are limited to frequency. These are called belt transects. They are used to obtain a general ‘overview’ or panorama of an area before starting more detailed work with quadrats.
An example of how to map an ecosystem and find the population density, abundance, and identify the biotic and abiotic factors that might affect the distribution of a species.
Mapping an ecosystem
- 1. Identify species
- 2. Identify density of organisms of the same species units generally per m sq.
- 3. Identify distribution of organism – where are the organisms found in a given area.
- 4. Understanding ‘tolerance’ tells us about the biotic and abiotic factors that are optimum for the survival of an organism. Tolerance affects distribution and density.
Tools to map an ecosystem
1. Quadrat - good for showing population density
Total individuals counted = Individuals/m sq.
Number of quadrats x quadrat size
2. Transect - good for showing distribution
A panorama in which height and distribution of species is shown. Useful to show how an ecosystem’s species are spread out and influenced by and abiotic factors. This can identify optimum range, tolerance and population density.
3. Capture and recapture method - only good for moving animals
This is best used for animals that move. The idea is to catch some animals and tag them and then let them go. They are going to wander off around the ecosystem A few days later you go back and try to catch the same number of animals. This time some will be tagged and some not tagged. From this info you can estimate the population size.
n1 = number caught and tagged initially
n2 = total number recaptured
n3 = number of tagged individuals recaptured
first time I capture 19 fish and tagged them
the second time I captured 17 fish and of the 17 . 8 were already tagged
so put this into the equation and population = (19 x 17 ) / 8 = 41 approx
How accurate is this type of sampling?
the short answer it is not accurate it provides an estimate. However you can improve the accuracy of your estimate by... Repeat the sampling more times..
Some common errors of this type of sampling include; Miscounting, having quadrats too close to eachother, capture recapture always in the same place.
Interactions between species
is a general term for the association between 2 different species.
They may take place as (define the following)
....The parasite feeds off the host The host has provided all the nutrition for the parasite...hook worms, fleas, ticks, bot flies, plasmodeum in malaria
.........Living together and both benefitting from the association..Rhino and tick bird,
Lichen is made up of a fungus and an alga living together
.....one species benefits but does no harm to the other...
shark and remora,
The most common form of interaction is competition. This can be seen as competing for food or shelter and may happen between different species . This is called interspecific competition. And competition between individuals of the same species when they compete for food , shelter and a mate.
3 Plant Organisation*
• Plant Cells
Plant cells are different to animal cells because they have a cell wall, large vacuole, and chloroplasts ( if the cells are in the leaf).
Photosynthesis occurs in the chloroplasts of leaves.
the reaction is ; carbon dioxide + water (and light in the presence of chlorophyll)--------> glucose and oxygen
How do the reactants get in?
1. Carbon dioxide enters the leaf
via tiny holes called stomata.
These holes are surrounded by a specialised cells called a guard cell
. They regulate the amount of carbon dioxide entering the leaf as well as the amount water leaving the leaf. Water enters the leaf through specialist tube cells
that extend from the root in a series that appears like train carriages. They are called xylem
The water and carbon dioxide diffuse into cells and then into the chloroplast where photosynthesis occurs. There may be hundreds of chloroplasts in each cell close to the surface of a leaf. Chloroplasts contain chlorophyl and this makes the leaves green.
Once photosynthesis has occurred the products must be removed from the cell. Oxygen diffuses out of the cell and then out of the leaf via the stomata. Glucose is transported via phloem
to other living cells to be used in respiration. ( C6H12O6 + O2 --> H2O + CO2 )
The phloem and xylem are bundled together in the vascular bundle
The key difference between xylem and phloem is that xylem carries water up from the root while phloem carries glucose down to the root ( and other cells for respiration)
Can be in 2 forms
1. aerobic respiration ( requires oxygen)
2. anaerobic respiration ( no oxygen requires, releases less energy overall)
• Plant cells all have a cell wall. This surrounds their cell membrane, nucleus, vacuole, chloroplast, mitochondria. Animals do not have cell walls. But they do have all the other organelles except for the chloroplast.
• The nucleus is like the brain and is the control centre of the cell. This is for both Plants and Animals
• Cell wall gives the plant structure (they don't have bones or skeleton) P only
• Vacuole is a sac that contains fluid or food. In plants they are big and animals they are tiny or do not exist.
• Mitachondrion this is the site of respiration where energy is released from the reaction of glucose and oxygen. P and A (The plural of mitachondrion is mitachondria - there are many mitachondria in a muscle cell)
• Chloroplast the site of photosynthesis where the energy from light converts carbon dioxide and water into glucose and oxygen. P only (only green parts of plants) Chloroplasts are found in the pallisade and spongy mesophyl cells (see diagram below) in a leaf. They are more concentrated on the sides that face the sun. You do not find chloroplasts in the vascular bundle or the epidermal layers.
Transverse section of the leaf
|note where the guard cells are also the airspaces inside the leaf.|
• Parts of the Plants – roots, leaves, stems and flowers
• Not all plant cells have the same shape. They may have a shape that suits their function. When a group of cells are arranged to perform a specialist role we call them tissues. Groups of tissues are arranged to form organs and groups of organs form a systems. Groups of systems form a multicellular organism ( like a plant or animal).
• Diagram of root hairs, (p190)￼
• Diagram of vascular bundles in plants (make sure they show the xylem and phloem) (p190)
Roles of Xylem and Phloem (p190)
Xylem carries water from the roots to the leaves. when water is lost form the leaves its called transpiration.
Phloem carries sugar rich fluid from the leaves to the roots and other parts of the plant. This called translocation
Stomate is hole in the surface of the leaf through which the water escapes. Guard cells regulate this loss of water. Plants don't lose all their water on a hot day because the guard cells swell up and this closes the stomata (stomata is plural for stomates).
This occurs in the cells that contain chloroplasts. Not all cells in the leaf contain chloroplasts the main ones are the palisade cells and the spongy mesophyl cells. You don not find chloroplasts in the xylem, phloem. or the epidermal cells.
Processes inside the plant
1 Transpiration - loss of the water through the leaf stomates.
2.Translocation is the movement of fluids from the leaf to the roots.
3. photosynthesis - carbon dioxide + water----(light in the presence of chlorophyl)--->glucose and oxygen
4. respiration oxygen + glucose ---> carbon dioxide + water + energy (stored in ATP)
Photosynthesis is the process where [plants can use the energy from sunlight to convert water and carbon dioxide into glucose and oxygen gas. To do this they require chlorophyll to trap the sunlight. Oxygen and carbon dioxide enter the plants leaves trough tiny pores called stomata (stomates). These pores can be open and closed by the guard cells which surround the pores. The guard fill up with water to close the pores and empty to open the pores. Guard cells prevent the leaf from withering and losing too much water. Guard cells control water lost by transpiration.
The green chlorophyll is kept inside an oragnelle in the leaf cells called the chloroplast. It is here where the photosynthesis takes place. only red , blue , yellow orange light is used in photosynthesis all the green light is reflected and this is why the plant look green. Because plants can make their own food we call them producers. This why they are always at the bottom of a food pyramid or the beginning of a food chain or web.
5.5 Cellular Respiration
All Cells Need Energy. They gets this from burning glucose in oxygen to make carbon dioxide and water and energy. This process occurs in the mitachondria. These are tiny organelles that are found inside all living cells (plant animal bacteria or fungi). This called aerobic respiration ( when oxygen is required). the product of aerobic respiration is ATP (energy)
ATP is short for Adenosine Tri Phosphate. It can store energy. It does this by this reaction
Adenosine Di Phosphate + Phosphate ------> Adenosine Tri Phosphate
Some cells can undergo anaerobic respiration. This process is where no oxygen required to produce energy. However other products are produced along with the energy and one of these is lactic acid. In a sprinter they use up all their available oxygen very early in a race and then rely on anaerobic respiration to provide the remaining required energy. If their bodies can not disperse the lactic acid they may get cramps.
Where does this fit into ecology?
Ecology is the study of interaction between organisms and the physical (abiotic) and biotoic factors in the environment. When we draw a food web we are describing the flow of energy through the ecosystem. This energy was originally sunlight which was trapped by green plants and converted by photosynthesis into glucose. When a the next consumer eats plants this glucose is passed into their bodies and used in aerobic respiration.
|OLD stuff below here|
5.4 Plant Responses
• Plant Moves
• Solar Powered
• Why Are Plants Called Producers?
• Why Are Plants Green?
Some organisims interact in unusual ways to help each other get the energy and nutrition they require. Eg parasites might live inside an animal or plant and directly suck out their glucose and nutrition from the host, mutualism is where both organism benefit and example is bacteria living inside coral.
Transects and quadrats are techniques used to sample an ecosystem. A transect can provide a snap shot of the size and distribution of the plant species and some animals that are found in the ecosystem. This in turn allows us to study how these species interact and predict what other species might form part of the food web. Quadrats are used to calculate the abundance (how many) of a species in an area. Quadrats also indicate the distribution of species that is where species are found.
When you combine all these techniques they used to calculate the density of a species within a ecosystem.
Example calculate the density of koala in Tootgarook
1. do a transect and find the manna gum that we know koala eat - if there are a lot we can expect some koala.
2. use quadrat method to sample some of the spaces along the transect. - this indicate distribution and abundance. we could use these to estimate the density of the manna gum.
3. finally we could random select some of the manna gum and count the number of koala or evidence of them (scats- poo) lots means lots of koala
Distribution is where they are found across the land
Density is how close together they are found.
5.4 Plant Responses
- Questions for the test
- 1. Write equation for photosynthesis and respiration
- Xylem do
- Phloem do _ in the plant
- examples of biotic factors and how they are measured are eg temperature measured by thermometer
- Chlorophyll is used for ___
- Transpiration is -----
- translocation is ---------
- The difference between aerobic and anaerobic is
- the difference between
- distribution and abundance is
- the difference between xylem and phloem is
- use your text book to draw and label a cross section of a leaf
- a cross section of a stem
- Draw a food and label the first order consumer the producer and the 3rd order consumer.
- Research the effect of 2 plant hormones - auxin, giberellins
Field Guide work book
* There is a cross-over of topics completed in Year 8 VELS 2012 and Year 9 Australian Curriculum 2013 – these topics should only need a quick review as a basis for learning the new informatio