Functioning Ecosystems Flashcards
3.2.1 Sequence and explain the transfer and transformation of solar energy into biomass through biotic components of an ecosystem, including:
a). converting light to chemical biomass
b). producing biomass and interacting with components of the carbon cycle
Why is the solar energy transformation inefficient for producers?
Primary producers, plants, use only 1-6% of the light that hits. The rest is either:
outside colour spectrum used in photosynthesis
reflected or transmitted
lost due to inefficiency in photosyntehsis pathway
reflection- some sunlight is reflected by clouds
radiation- some light energy that hits earth is radiated back into space
absorption- chlorophyll only absorbs certain wavelengths of light
3.2.1 Sequence and explain the transfer and transformation of solar energy into biomass through biotic components of an ecosystem, including:
a). converting light to chemical biomass
b). producing biomass and interacting with components of the carbon cycle
Explain the differences between an autotroph and a heterotroph.
Autotrophs use light energy and inorganic molecules (e.g. CO2 and H2O) to make organic compounds (known as carbon fixation). For example, photosynthetic autotrophs such as plants use energy from light to “fix” carbon during photosynethsis. Heterotrophs on the other hand depend directly on autotrophs for nutrients and energy. They are subdivided into five groups based on their diet. Herbivores are usually the autotrophs or producers, carnivores, detrivores (eat small particles of dead organic matter, decomposers (secrete enzymes to break down DOM), and omnivores.
3.2.1 Sequence and explain the transfer and transformation of solar energy into biomass through biotic components of an ecosystem, including:
a). converting light to chemical biomass
b). producing biomass and interacting with components of the carbon cycle
What is the biomass?
Biomass is the total quantity or weight of organisms in a given area or volume.
3.2.1 Sequence and explain the transfer and transformation of solar energy into biomass through biotic components of an ecosystem, including:
a). converting light to chemical biomass
b). producing biomass and interacting with components of the carbon cycle
What is the biomass?
Biomass is the total amount of biological matter in an organism (or group of organisms). It consists of carbohydrates, lipids, proteins, and other organic molecules. The energy in these molecules is available to other organisms that consume the plant or other living things as their energy source.
3.2.1 Sequence and explain the transfer and transformation of solar energy into biomass through biotic components of an ecosystem, including:
a). converting light to chemical biomass
b). producing biomass and interacting with components of the carbon cycle
How is biomass formed through the carbon cycle and transferred to other consumers?
Biomass forms when carbon in the CO2 is transferred into glucose by the plant during photosynthesis to form solid substances such as strach and cellulose in plant tissue, and allow plant to grow. The energy transfer concept is when energy is transferred through the ecosystem in the form of biomass through a food chain.
3.2.5 Define ecological niche in terms of habitat, feeding relationships, and interactions with other species.
Define ecological niche.
The role and space that an organism fills in an ecosystem, including all its interactions with the biotic and abiotic factors of its environment. An ecological niche describes the finctional role of an organism in its ecosystem, including its habitat and all its interactions with the ecosystem.
An organism’s niche includes:
-How the species responds to the distribution of resouces
-How it alters those resources for other species
3.2.5 Define ecological niche in terms of habitat, feeding relationships, and interactions with other species.
Ecological niches are unique to each species
Even when a number of species live in the same habitat, there will always be some differences between their niches, to allow them to avoid competition.
3.2.5 Define ecological niche in terms of habitat, feeding relationships, and interactions with other species.
Provide an example of a niche.
Habitat: wooded regions, wetlands
Behaviours: often found in trees, can burrow, barking call attracts mates
Feeds on: small insects
Eaten by: birds, snakes, racoons
Impact on ecosystem: limit insects, aerate soil, serve as a food source
3.2.5 Define ecological niche in terms of habitat, feeding relationships, and interactions with other species.
Contrast fundemental and realised niche.
Fundemental niche is the entiire set of conditions under which an animal can survive and reproduce itself. It is larger then the realised niche, involves no competition for resources and no predators are considered. The realized niche is the set of conditions actually used by a given animal after interactions with other species (predation and especially competition) are accounted for. It is smaller than the fundemental niche.
3.26 Understand the competitive exclusion principle
What happens when two niches overlap?
No two species can occupy the same niche indefinitely due to interspecific competition which may enforce force an organism to occupy a smaller niche. If two species do occupy the same niche, one of three things will occur:
1. Extinction/exclusion of one species - known as competitive exclusion principle
2. Niche is split between the species - known as resource partitioning
3. Two simialr species will evolve to become different from each other - character dispalcement
3.26 Understand the competitive exclusion principle
The competitive exclusion principle states…
That two species with identical niches cannot coexist indefinitely without one becoming extinct or being driven out because of competition for limited resources. When one species has even the slightest advantage over another, the one with the advantage will dominate in the long term. This leads either to the extinction of the weaker competitor or to an evolutionary or behavioral shift toward a different ecological niche.
Describe resource partitioning.
Similar species may occupy the same habitat, but consime the resources in different ways. This is linked to sympatric speciation. Here, similar lizards for example. move to different parts of a forest depending on the preferred environmental conditions.
Describe character displacement.
Character displacement is the term used to describe an evolutionary change that occurs when two similar species inhabit the same environment. Under such conditions, natural selection favors a divergence in the characters–morphology, ecology, behavior, or physiology–of the organisms. For example, a species may become more exaggerated to allow them to use the availiable resources differently in the future.
Contrast competitive exclusion and resource partitioning.
Competitive exclusion principle tells us that two species can’t have exactly the same niche in a habitat and stable coexist. It therefore doesn’t support the coexistance of two species competing for identical resources. Resource partioning is the division of the niche by species to avoid comptition for resources. It helps the species to coexist since it creates less direct competition between them.
3.2.8 Define keystone species and understand the critical role they play in maintaining the structure of a community.
A plant or animal that plays a unque and cruical role in the way an ecosystem functions. If a keystone system is removed, the ecosystem becomes much less stable and its structure changes.
