4.1 Species & Ecosystems Flashcards
Define “Species”
Groups of organisms that can interbreed and produce fertile, viable offspring
What happens when species crossbreed and produce offspring?
The offspring is infertile and inviable
Define “Population”
A group of organisms of the same species that live in the same area and time
Explain “Reproductively isolated”
Organisms in different regions (i.e. different populations)
If they are they are the same species; interbreeding is functionally possible, however unlikely.
Define “Community”
Different populations of species living and interacting together in a given habitat
Define “Habitat”
Environment where species usually live, or location of a living organism
Define “Ecosystem”
A community and it’s abiotic environment (i.e. habitat)
Define “Ecology”
The study of relationships between living organisms and their environment
What are the two ways living organisms obtain chemical energy(modes of nutrition)?
Autotroph; synthesize their own organic molecules
Heterotrophs; ingest organic molecules
Some are both
What type of nutrients do Autotrophs obtain? State the 4 examples.
Obtain inorganic nutrients from abiotic environment; carbon, oxygen, nitrogen, phosphorus.
How do Autotrophs gain nutrients?
Synthesize it’s own organic molecules from simple inorganic substances (e.g. CO2, nitrates) from their abiotic environment
Through processes such as photosynthesis and chemosynthesis
Why are Autotrophs also known as “Producers”?
Because they synthesize (produce) their own nutrients
How do Heterotrophs gain nutrients?
Obtain organic molecules from other organisms
What is the difference between Autotrophs and Heterotrophs?
Autotrophs synthesize their own nutrients.
Heterotrophs obtain organic molecules from other organisms, they cannot produce their own organic molecules.
Define “mixotrophs”
Certain unicellular organisms that may use both autotroph and heterotroph methods of nutrition
Define “Consumer”
Heterotrophs that ingest living or recently killed organic matter
What are they three types of consumer?
Herbivore, carnivore and omnivore
Define “herbivore”
Heterotrophs that feed on principally plant matter
Define “carnivore”
Heterotrophs that feed on principally animal matter
Define “omnivore”
Heterotrophs that feed on both plant and animal matter
Define “Scavanger”
Heterotrophs that feed on dead or decaying carcasses
State the different classifications of heterotrophs
Consumers, scavengers, detritivores and saprotroph
Define “detritivores”
Heterotrophs that ingest non-living matter such as humus and detritus
Define “detritus”
Dead, particulate organic matter, such as decaying organic material or fecal matter
Define “humus”
Decaying leaf litter intermixed with topsoil
Define “saprotrophs”
Heterotrophs that live on non-living organic matter and release enzymes to absorb nutrients
Define “Nutrients”
Inorganic material required by organisms
What is the purpose of nutrient cycling?
Nutrient supply on earth is finite; cannot be created and is in limited supply. Supply of inorganic nutrients is maintained through cycling
Examples of Nutrients
Carbon, nitrogen, phosphorus
Outline how chemical elements are recycled after use
- Autotrophs obtain nutrients from air, water and soil; nutrients are converted to organic compounds
- Heterotrophs ingest organic compounds and use for growth and respiration; inorganic byproducts are released
- Organism dies, saprotrophs decompose remains; inorganic matter is freed into soil
- Reintroduction of inorganic nutrients into soil; continual supply of raw materials for autotrophs is achieved
What are the 3 main components of sustainability?
- Energy availability
- Nutrient availability
- Recycling of wastes
What is exchanged between a sealed mesocosm and the surrounding external environment?
Energy
What is the purpose of the Chi-squared test in ecological research?
Test whether two species tend to live together
Why do animals in the highest tropic levels tend to be largest in body size but few in numbers?
Energy loss through the food chain
