Functioning Ecosystems (PPT7-8) [U3/ T2] Flashcards
Can energy be recycled?
No
How do ecosystems receive new energy?
- From an outsie source
- Most commonly the sun
ecosystems must also have…?
organisms equipped to capture the suns energy and transform it into a useable form
What are the two types of energy transformations?
- Photosynthesis
- Cellular respiration
What is photosynthesis?
Green plants, algae and some bacteria use the suns light energy to produce chemical energy in the form of glucose
What is cellular respiration?
The process by which organisms break down energy-rich molecules (e.g. glucose) to release the energy into a useable form
What is the two types of classification relating to the obtaining of energy
- Autotrophs (produces)
- Heterotrophs (consumers)
What are the two types of producers?
- Photosynthetic autotrophs
- Chemosynthesis autotrophs
How do Photosynthetic autotrophs produce energy?
use light energy from the sun to make glucose from CO2 and H2O.
how do Chemosynthesis autotrophs produce energy?
use energy from energy-releasing chemical reactions between inorganic molecules to make glucose.
List the major tropic levels in order
1) Producers
2) Herbivores
3) Primary carnivores
4) Secondary carnivores
5) Omnivores
6) Detritivores & Decomposers
Define food chain
The sequence of organisms, each which is a source of food for the next
Which direction do arrows travel in food chains
- Food to feeder
- e.g. Producer to herbivore
What does a food web accomplish?
Shows the connections of all organisms within an ecosystem
What is the trophic level producers source of energy?
What organisms does it include?
- Solar energy
- Green plants, photosynthetic protists & bacteria
What is the trophic level herbivores source of energy?
What organisms does it include?
- Producers
- Grasshoppers, water fleas, antelope, termites,
What is the trophic level primary carnivores source of energy?
What organisms does it include?
- Herbivores
- Wolves, spiders, some snakes, warblers
What is the trophic level secondary carnivores source of energy?
What organisms does it include?
- Primary carnivores
- Killer whales, tuna, falcons
What is the trophic level Omnivores source of energy?
What organisms does it include?
- Several trophic levels
- Humans, rats, possums, bears, raccoons, crabs
What is the trophic level Detritivores & decomposers source of energy?
What organisms does it include?
- Consume & recyle dead plant/ animal material
- No assigned trophic level
How can energy flow be represented?
By food chains
How is energy lost?
- Heat to the atmosphere
- During metabolic reactions within organisms (respiration)
- Faeces and urine
What is the 10% rule?
States that the total energy content of a trophic level in an ecosystem is only about 0ne-tenth that of the preceding level.
Why is only 10% of energy passed on?
The remaining 90% is transformed by cellular metabolism into eventual heat energy and lost to the atmosphere or remains as chemical energy in the uneaten portion of the organism and its body waste.
The energy available to each trophic level will always…
finish the statement
equal the amount entering the trophic level minus total losses to that level.
What are the three ecological pyramids used?
- Energy
- Biomass
- Numbers
What does a pyramid of numbers show?
The total number of individual organisms at each level in the food chain of an ecosystem.
What does the pyramid of biomass display?
- Dry weight typically used as a measure
- Water content of organisms varies
- Organism size is taken into account
- May be inverted
What does a pyramid of energy show?
The producers highest quantity of energy that decreases at each level of the food chain.
THE WATER CYCLE (Yellow sticky note)
CN11,
CARBON CYCLE (Yellow sticky note)
CN11
NITROGEN CYCLE (Yellow sticky note)
CN11
Define Transformation
Changing its form
Define transfer
Moving to another location
Define habitat
The place or space in which an organism lives out its life.
Define niche
The functional position or role a species plays in a community; its total way of life.
What are the two types of niche
- Fundamental
- Realized
Define fundamental niche
The full range of environmental conditions (biological and physical) under which an organism can exist.
Define realized niche
The niche that is actually occupied.
It is narrower than the fundamental due to pressure from and interactions with other organisms.
Define competition
The active demand between two or more organisms for a resource
What are the two types of competition
- IntrAspecific
- IntERspecific
Define IntrAspecific competition
(sAme = IntrA)
Competition between members of the same species
Define IntERspecific competion
(diffERent = IntERspecific)
Competition between different species sharing a habitat
What is niche partitioning?
When does it occur?
Niches are separated to avoid competition
Niche partitioning occurs when different species live in close proximity to each other and use slightly different resources.
What is the competitive exclusion principle
The fact that no two species can occupy the same niche is called the Gause competitive exclusion principle
How is competition alleviated?
Provide an example
Resource partitioning E.G. - Feeding at different times (Temporal) - Feeding at different heights (Depth) - Different sized prey
Define adaptation?
An inherited feature of an organism that enables it to survive and reproduce in its habitat
What are the three types of adaptation
Behavioural - the way an organism acts
Physiological - the way the body works
Structural - the way an organism is structured (its physical features)
Define a specialised niche
Provide an example
- Very well-defined or narrow physical, biological or chemical requirements for survival
- More susceptible to extinction
E.G.
- Dugong: requires seagrass and warm calm water
Define a generalised niche
Provide an example
- Species which can exist in a broad range of conditions
- In the face of change, organisms occupying a broader niche have a better chance of survival
E.G.
- Humans, cockroaches, flies, rats
Define a keystone species
A plant or animal that plays a unique and crucial role in the way an ecosystem functions.
They play a pivotal role and their elimination or severe reduction can significantly alter an ecosystem.
Provide an example of a keystone species
- Elephants - alters vegetation structure
- Termites - breaks down plant cellulose
- Ochre star - feeds on mucsles
