Ecosystems Flashcards
(99 cards)
1
Q
Define population
A
A group of individuals of the same species living in the same place (habitat) at the same time
2
Q
Define environment
A
Collective term for the conditions in which an organism lives
Includes abiotic and biotic conditions
3
Q
Define biome
A
One of the world’s major ecosystems usually named after the dominant vegetation of the area
Can be terrestrial and aquatic
4
Q
What are 8 different terrestrial biomes/ecosystems?
A
Tropical rainforest Scrubland Temperate rainforest Desert Open woodland Alpine Grassland (savannah) Sclerophyll forest
5
Q
What are 4 different aquatic biomes/ecosystems?
A
Freshwater
Eg. Lake, billabong
Mangrove estuary
Marine
Eg. Coral reef, rock platform, deep sea
Estuarine
6
Q
What are the two factors affecting the survival of an organism?
A
Biotic
Abiotic
7
Q
What are biotic factors?
A
Living or biological factors that can affect the survival of an organism
8
Q
What are abiotic factors?
A
Non-living or physical and chemical factors that can affect the survival of an organism
9
Q
Examples of abiotic factors
A
pH of soil or water, temperature, turbidity, presence of dissolved ions or gases (O2, CO2, nitrates), availability of water, salinity in the soil/water, light intensity and humidity
10
Q
Examples of biotic factors
A
Includes competition for food and nesting sites, predation, parasitism, food sources and disease causing pathogens or decomposes which break down the wastes.
11
Q
What is Viscosity?
A
thickness of a medium e.g. water or air, and its ability to resist internal movement through it
12
Q
What is the relationship between Viscosity and the organism?
A
The thicker the medium, the higher the viscosity and the more internal friction it offers to the organism
Viscosity affects the ability of an organism to move around.
13
Q
How does viscosity compare on terrestrial and aquatic environments?
A
Water is more viscous than air so many aquatic animals are more streamlined than land animals so they can move rapidly through the water.
14
Q
What are 7 comparisons between aquatic and terrestrial environments?
A
Viscosity Buoyancy Pressure Temperature variation Availability of gases Availability of water Light penetration
15
Q
What is Buoyancy?
A
the force giving upward thrust.
16
Q
How is buoyancy determined?
A
Determined by the density of the medium and determines the floating ability of the organism.
17
Q
How does buoyancy compare on terrestrial and aquatic environments?
A
Air provides little upthrust, so most terrestrial organisms need a skeleton or a means to support their own weight.
Salt water provides more upthrust than freshwater.
18
Q
What is pressure?
A
force exerted on a body by its medium.
19
Q
How does pressure compare on terrestrial and aquatic environments?
A
In water pressure depends upon depth – the deeper the water the higher the pressure.
On land pressure depends on altitude – the higher the altitude, the lower the pressure
20
Q
What is temperature variation?
A
is of importance, as many chemical reactions in the body are temperature dependent. Enzymes denature or become inactive with variations in temperature.
21
Q
How does temperature variation compare on terrestrial and aquatic environments?
A
Usually temperature of water varies less than air temperature on land.
If the body of water is large e.g. ocean, temperature variation is much less than in a small body of water such as a small pond.
Water temperature decreases with depth
22
Q
What does the availability of gases mean?
A
e.g. oxygen and carbon dioxide, and ions e.g. nitrates, phosphates and calcium ions. Such will determine whether a particular environment is suitable for a particular species.
23
Q
How does availability of gases compare on terrestrial and aquatic environments?
A
Gases are more readily available in air than in water e.g. a litre of air contains 210 cm3 oxygen while a litre of water at 15 degrees C contains about 6 cm3 oxygen
Availability of gases also depends on the rate of diffusion – diffusion is greater in air than water.
24
Q
How does availability of gases affect aquatic environments?
A
In water the amount of dissolved gases depends upon factors such as temperature, depth and turbulence.
Hot water holds less oxygen than cold water
25
What does availability of water mean?
major concern for animals and plants on land and in water
26
How does the availability of water affect terrestrial organisms
On land many organisms keep cool by the evaporation of sweat, but this can lead to dehydration.
The extent and depth of root systems of many land plants is determined by water availability
27
How does the availability of water affect aquatic organisms?
In aquatic environments water availability can be a problem due to osmosis. Organisms in salt water tend to lose water by osmosis.
Organisms in fresh water tend to gain water by osmosis.
28
How does the light penetration affect terrestrial environments?
especially important for plants for photosynthesis.
Most terrestrial environments have good light penetration.
Many plants have specific adaptations for full sun/partial sun/full shade.
Tropical rainforests have vertical levels with different amounts of light penetration, ranging from full sunlight at the emergent uppermost level to forest floor which receives very little sunlight.
29
How does the light penetration affect aquatic environments?
Aquatic habitats light penetration is a critical factor as light only penetrates to about 100 metres.
30
What are 3 samplers for biotic components?
```
Sweep nets
Water samplers
Plankton net
Kick sampling
Pitfall traps
Longworth small mammal trap
Pooter or aspirator
Tullgren funnel
Beating tray
```
31
What are 3 samplers for abiotic components?
Anemometers – wind speed
Thermometers – temperature
Barometers – atmospheric pressure
Rain gauges - rainfall
pH meter- acidity or basicity of an aqueous solution.
Dissolved oxygen content – oxygen levels
Wave action –
Light meter- light intensity
Hygrometer - humidity
Turbidity -amount of suspended material in water
Chemical testing kits – soil or water nutrients/salinity
32
What are the three things in ecosystems interactions that are continually occurring?
between the living (biotic) community and its abiotic surroundings.
within the abiotic surroundings
within the living community. Interactions within the community of an ecosystem may involve members of different species.
33
Give an example to the interactions that are continually occurring between biotic and abiotic factors.
eg. Plants capture light energy and take up carbon dioxide from the atmosphere and water and mineral nutrients, such as nitrates from the soil.
34
Give an example to the interactions that are continually occurring within the abiotic surroundings
eg. A lack of rainfall over an extended period causes the water flow in rivers to fall and creeks to dry out.
35
What are the 7 types of interactions within ecosystems?
Mutualism
Commensalism
Predator/prey
Parasite/host – endoparasite and ectoparasite
Collaboration
Competition – intraspecific and interspecific
Disease
36
What is symbiosis?
Symbiosis is a term for interactions in which two organisms live together in a close relationship that is beneficial to at least one organism.
There are three kinds of symbiotic relationship; mutualism, commensalism and parasites.
37
What are the three types of symbiotic relationships?
mutualism, commensalism and parasites.
38
What is a mutualism?
both organisms benefit from the relationship
39
Give 3 examples of a mutualistic relationship
Examples include: corals have a close association with a type of algae. The algae live, reproduce, photosynthesize and utilize waste products of the animal hosts (coral). In turn, the coral uses the oxygen and food produced by the algae to grow, reproduce and form its hard skeleton.
oxpeckers and zebras
eg. oxpeckers benefit by having a readily available source of food. While zebras benefit from having the bugs removed. Oxpeckers also fly high and make noise to alert nearby animals to the impeding danger
pistol shrimp and goby fish
the shrimp is able to dig a burrow to live in but is relatively blind and cannot detect approaching predators, the goby fish uses the burrow for protection from predators and in return acts as 'eyes' for the shrimp. In the day the shrimp maintains continual contact with the goby's tail, which the goby will flick several times if a predator approaches. They share the burrow at night.
40
What is commensalism?
one organism benefits in the relationship and the other is unaffected
41
Give 2 examples of commensalism
epiphytes (climbing plants) benefit by living on a host tree that provides a position closer to the light and a catchment for water and mineral nutrients.
cattle egret and cattle. cattle egret will eat insects that have been disturbed when cattle forage
hermit crab taking homage in a shell
Remora fish and shark
42
What is Parasitism?
one organism benefits in the relationship (parasite), whilst the other is harmed (host). Parasites gain nutrition and protection from their hosts.
43
What are the two types of parasites?
Parasites which live on the surface of their host are ectoparasites. Examples include: fleas, ticks, lice (or nits!) and leeches.
Endoparasites live internally in their hosts and include: tapeworms, roundworms, whipworms and malaria.
Plant parasites include, mistletoe, toothwort, cuscuta
44
What is competition?
occurs between organisms for limited resources such as food, nesting sites, territory and mates. When resources are limited, those organisms which compete the best will survive, while those that do not will be forced to migrate and move away or die.
45
What is collaboration (2) ?
involves different species benefiting each other
such as birds, insects or mammals assisting in flower pollination. In collecting pollen and nectar, the pollinator passes the pollen on to the next flower.
occurs between organisms in a group for protection against predators
( schools of fish, flocks of birds etc), for protections against the cold (huddling penguins) and for social organisation.
This differs from mutualism as there is not a continuous association.
46
What is predation?
occurs when one organism (predator) eats another (prey)
47
What is disease?
the presence of disease causing organisms (pathogens) reduces the survival of others by causing illness, or indirectly by weakening the organism so that it becomes easier prey for predators.
Examples: viruses (HIV, swine flu, bird flu), bacteria (tuberculosis) and protozoa (malaria).
48
Give an example of a competitive relationship and interaction
Sea anemones compete for the same food source with other species
They can detect slight genetic variations in intruders of the species.
Both discharging a battery of stinging cells
49
What are the two types of relationships between living things?
Intraspecific
Interspecific
50
What are intraspecific relationships?
Competition between members of the same species
Eg. Pack of wolves
51
What is an interspecific relationship?
Competition between members of different species
Eg. Wolves and rabbits
52
What are keystone species?
Species that is not necessarily abundant in an area but have strong control on the structure of the community due to its role or ecological niche
The presence is critical to the maintenance and survival of the community
53
Give an example of a keystone species
Cassowary is the keystone species of tropical rainforests, they are the rainforest's gardener, they maintain the balance and diversity through its role as a seed disperser
Sea stars prey on sea urchins, mussels and other shell fish that have no other natural predator
Northern quoll hunts a wide range of prey and also plants. Their consumption helps maintain balance and they also consumer cane toads.
Acorn banksia, honey eaters help pollinate other plants. Loss of this plant will be less honey eaters and less pollination
54
What are Flagship species?
Species chosen to represent an environmental cause, a defined habitat or campaign
Used to raise awareness
Eg. Bilby, Panda etc...
55
What are Umbrella species?
Wide range species that has a similar requirement to the other species so that protection of this species offers protection to other species.
Used for conservation strategies and to work out the location and range of potential nature reserves
56
Define Niche
Way of life of an organism and the role it plays in an ecosystem
Where it lives, eats, feeds, when its active, biotic factors (predators), its tolerance to abiotic factors (temperature)
57
What is a fundamental niche?
Region of the environment within which a species can persist indefinitely
No competition
58
What is a realised niche?
Results from competition and is the area which the species is most highly adapted and most commonly found.
59
What is niche separation and overlap?
Resource partitioning and niche specialisation caused by separation
60
What is niche separation?
No competition present and the fundamental niche is occupied
61
Give an example of niche separation.
Species A eats insects of small sizes and Species B eats insects of large sizes. Therefore, A and B do not compete for the same food resource
62
What is niche overlap?
When competition occurs and the realised niche is occupied
63
Give an example of niche overlap
Species A eats insects of sizes 5-7mm and Species B eats insects of sizes 6-10mm. Therefore both species compete for the same resource as their preferences overlap.
64
Describe a resource utilisation curve
Y-axis: intensity of resource utilisation
X-axis: resource gradient
Where Species A has a narrow niche breadth and is a specialist
Where Species B has a wide niche breadth and is a generalist.
Both overlap at a point called a niche overlap
65
How can we minimise competition?
Resource partioning
- When this happens niche separation occurs
- If two species use the same resource in similar ways, they show niche overlap.
66
What is the relationship between niche separation and level of competition?
The greater the niche separation of two species the smaller the level of competition
67
What is the relationship between niche overlap and the intensity of competition between 2 species?
The greater the niche overlap, the greater the intensity of competition between 2 species
In general, 2 or more species cannot occupy the same niche in the same community for an extended period, these species will be in direct competition
68
What are some species that can exploit the resources will displace the others from the habitat?
Rabbits in Australia
They somethings occupy a broader niche than they actually need, as it is the competition from other species that stops them from doing so.
69
What is the competitive exclusion principle?
If two species have the same mode of life and use the same resources, they will be unable to coexist.
70
What is the tolerance range?
The distribution (where organisms are found) of a species is affected by environmental factors (abiotic ).
Abiotic factors include: temperature, oxygen concentration, light intensity, pH (in water), carbon dioxide concentration etc
71
What does a tolerance range identify?
A tolerance range identifies the variation within organisms which can survive.
Not all organisms are exactly the same, and some members of a species have a higher tolerance than others.
72
What are tolerance limits?
Tolerance limits are the limits of an abiotic factor beyond which an organism will not survive.
If an abiotic factor has a value above or below the tolerance range of an organism, that organism will not survive unless the organism can escape from or somehow compensate for the change.
73
How do some animals escape from the extremities?
In some species, migration is an escape behaviour, in others it is to retreat underground.
74
Examples of some incidents where animals have. (3)
the female polar bear in the Artic winter hibernates in a den underground.
The insects in winter die due to the drop in temperature below freezing.
As well, the spinifex hopping mouse in arid Australia burrows underground when temperatures increase.
75
What are the two most important processes in any ecosyste?
The two most important processes in any ecosystem are the one way flow of energy through the system and the chemical recycling of matter.
76
How does energy energy enter the ecosystem?
As light energy (sun), through a process called photosynthesis .
77
How much do plants convert light into chemical energy % and what happen to the remaining percentage (4)?
Green plants convert approximately 2-10 percent of the visible light falling on their leaves into chemical energy.
The remaining 90 percent is:
- Reflected by the leaf
- Transmitted through the leaf
- Lost as heat during photosynthesis
- Or is as wavelength that cannot be used in photosynthesis.
78
What is the percentage of energy released as heat energy and as ATP for cellular respiration?
60% of the energy released in this reaction is in the form of heat energy and 40% is ATP.
Heat is always released when an energy conversion occurs.
79
What are the three ways energy is taken in when one organism consumes another?
Body processes and maintenance such as digestion, reproduction and cell processes.
Body tissue (biomass) is stored.
Lost as heat energy to the environment
80
What is the percentage of energy input is taken when one organism consumes another on which is taken through body process and maintenance?
Approximately 30% of energy input.
81
What is the percentage of energy input is taken when one organism consumes another on which is taken through body tissue?
Approximately 5-10% of energy input.
82
What is the percentage of energy input is taken when one organism consumes another on which is lost through heat energy to the environment?
Approximately 60% of energy input
83
What energy is passed to the next consumer?
Only the biomass (stored energy in body tissues) is available to the next trophic level consumer.
The energy available to each trophic level will always equal the amount entering that trophic level, minus the total losses to that level.
84
What losses are there when energy is transffered to the next trophic level? (3)
The losses are: body processes, heat loss and organic wastes.
Heat will leave the ecosystem.
Other losses include faeces, urine and dead tissue will become part of detritus and may be used by other organisms decomposers and detritivores) in the ecosystem.
85
How much energy comes into the producer and how much is lost and how much is available for the next trophic level? (example)
120 units of energy enters.
100 units is lost as heat, dead tissue and used to maintain body function.
The remaining 20 units of energy is biomass /body tissue and is available to the next trophic level, the Herbivore.
86
How much energy is gained from the producer, to the herbivore and how much is lost and how much is available for the next trophic level? (example)
Herbivore – 20 units of energy enters
18 units is lost as heat, detritius or used to maintain body functions
The remaining 2 units is available to the Carnivore.
87
What is the 10 percent rule?
About 10 percent of energy going into one trophic level is available for transfer to the next trophic level in the form of organic matter (biomass) in tissues.
The remaining 90 percent is lost as heat and detritius.
88
What does the 10 percent rule calculate?
calculate the cost in energy terms of producing the organic matter in the tissues of organisms (biomass) at different levels.
89
Give an example of 10 percent rule.
We can estimate that 100 gram of plant matter (leaves) can produce 10 gram of caterpillar tissue. This amount of caterpillar tissue can produce 1 gram of spider tissue.
So 1 unit of carnivorous spider tissue is 10 times more expensive to produce than 1 unit of caterpillar tissue.
90
What are endemic species?
species that is native to a particular geographic region and is not introduced
91
What is the difference between population and community?
A population is a group of individuals belonging to the same species, while a community is the sum of the different species.
92
What is the difference between environment and habitat?
an environment is the abiotic and biotic factors of an area, while a habitat is an area where a species lives within an ecosystem.
93
What is the difference between biotic and abiotic?
biotic are the living components of an ecosystem, while abiotic are the non-living components
94
What is the difference between open and closed ecosystems?
Closed ecosystems are ones that do not have any inputs (exchanges of energy from the surrounding environment) or outputs (exchanges of energy from within the ecosystem). Open ecosystems are ones that have both inputs and outputs.
95
Explain how the predator-prey relationship shapes the biodiversity of an ecosystem
is the release of nutrients into the soil caused by decomposing animal carcasses left behind by predators, which allows for micro-organisms to survive in the ecosystem
large effect on the prey population and plant population as the animals the predator hunts feeds on seeds of plants, and so since predators cant digest it, it poops it out and helps with germination
96
What are pollinators?
an organism that hunts another organism for its food
97
What are seed disperser?
an organism that feeds on fruits and seed for nutrition and, when the animal defecates, it deposits the seeds in a new location where they can germinate and grow
98
What are two different ways in which species can avoid directly competing for the same resources in their habitat?
by exploiting the resources within different microhabitats
by exploiting the same resources at different times of the day or year
99
What is the effect of the number of different plants on the number of animal species?
Different animals deef on different parts of the plant. Therefore there are more animal species than plant species. Whenever there are more plant species there will be many more animal species
