Chapter 4- Ecology And Ecosystems- Communities And Eco-systems Flashcards
Define habitat
Environment in which species lives in
Define population
Group of organisms of the same species who live in the same area at the same time
Define community
Group of populations living and interacting in the same area
Define ecosystem
Community and its abiotic environment
Define ecology
Study of relationships between living organisms and between organisms and their environment
Define an autotroph
Organism that synthesis it’s organic molecules from simple inorganic substances (e.g CO2 and nitrates)
What are autotrophs?
Producers
Define a heterotroph
Obtains organic molecules from other organisms
What are heterotrophs?
They are consumers
Define a consumer
Organism which ingests other organic matter that is living or recently killed
Define detritivore
Organisms that ingests non-living organic matter
Define saprotroph
Organisms that lives in or eats non living organic matter, secreting digestive enzymes into it and absorbing the products of digestion
What do food chains show?
Food chains show linear feeding relationships between species
What do you arrows represent in food chains?
Arrows represent transfer of energy as one organism is eaten by another
What is the first organism in a food chain sequence and what is it followed by?
The first organism in the sequence is the producer followed by consumer
Draw three food chains including land pond and ocean
Do it Martha
What do food web show?
Food web show how food chains are linked together into more complex fitting relationships within a community
In food webs what can hold more than one trophic level
more than one producer and consumer occupy Multiple trophic positions
Define trophic level
Trophic level refers to the position it occupies in a food chain
What is trophic level one
Producer
What is trophic level two
Primary consumer
What is trophic level three
Secondary consumer
What is trophic level four
Tertiary consumer
Construct a food web containing up to 10 organisms
Fucking do it
Why is light useful for almost all communities
All green plants some bacteria= photo trophic they use light as a source of energy for synthesising organic molecules
What is light at the initial source for?
Almost all communities
How does energy enter most communities
Energy enters most communities as light its absorbed by autotrophs e.g. plants And converted into chemical and converted into energy by photosynthesis
After energy enters most communities as light how does energy then get past the primary consumer?
Energy then gets passed to the primary consumer herbivore when They eat the plant and then get past the successive consumers carnivores as they eaten in turn
How much energy is passed from one trophic level to another and where does the rest go?
Only about 10% of energy is passed from one trophic level to another the rest is lost
How much percentage of energy is lost from trophic level to trophic level
90%
What can energy be lost as when moving from trophic level to trophic level
It can be used as heat, used up during cell respiration, be excreted in faeces or a remain unconsumed as it uneaten part of the food
Explain the reason for the shade of the pyramids of energy
The pyramid is a graphical representation of the amount of energy in each trophic level in a food chain
What unit are the pyramids shown in
They are expressed in units of energy per area per time
Why will a pyramid never been inverted (2nd law of thermodynamics)(
Pyramids will never be inverted as energy is stored in one is always lost when transferred to the next source–> application of the second law of thermodynamics
What should each level of the pyramid be?
1/10 of the level before it
Can energy be recycled
No
What is an eco system powered by?
A continuous influx of new energy from an external source (eg the sun)
Nutrients are required by what? And what?
An organism- which recycles an ecosystem as food (living or dead)
What do autotrophic activities of producers produce?
Organic material from inorganic sources, which are then fed on by consumers
What happens when heterotrophic organisms die?
Inorganic nutrients returned to soil and are used by plans —-> thus energy flows through an ecosystem, while nutrients cycle with them
What do decomposes do?
Recycle nutrients–> Free inorganic materials from the dead bodies and waste products of organisms, ensuring a continual supply of raw materials from the producers
Define species
Group of organisms which can interbreed, and produce fertile offspring
