Ecology Flashcards
Define food chain.
A food chain is a series of organisms through which energy is transferred in the form of food. Each stage in a food chain is known as the trophic level.
Why are shorter food chains more efficient than longer food chains?
90% of total energy is lost during transfer from one trophic level to the next. Less energy is lost within a shorter food chain.
What do producers do?
Producers convert radiant energy from the sun into chemical energy during photosynthesis and produce complex organic molecules from inorganic raw molecules.
How do consumers obtain energy?
Feeding on other organisms.
What is a pyramid of numbers?
A pyramid of numbers allows us to compare the number of organisms in each tropic level at a particular time. It is usually broad based and narrow towards the top.
Why would a pyramid of numbers be inverted?
1) organisms of one trophic level are parasitic
2) many small organisms on one level feeds on a large organism on another level
What is a pyramid of biomass?
A pyramid of biomass allows us to compare the mass of organisms present in each trophic level at a particular time.
Why would a pyramid of biomass not be pyramid shaped?
The organisms are rapidly reproducing.
How is carbon dioxide removed from the environment via the carbon cycle?
Photosynthesis converts carbon dioxide into the atmosphere into carbohydrates. It is used to manufacture other organic compounds like fats and protein. It might then become part of animals or fossil fuels.
How is carbon dioxide released into the environment?
1) respiration (glucose broken down into carbon dioxide)
2) combustion of fossil fuels
3) decomposition (dead matter broken down into carbon dioxide)
Why is the carbon cycle important?
- it ensures a continuous supply of carbon dioxide for plants to carry out photosynthesis
- it enables energy to flow through the ecosystem since photosynthesis traps solar energy in carbon compounds.
What are carbon sinks and list 2 examples.
Carbon sinks are areas that absorb more carbon than they release. 2 examples are oceans and forests.
What is the ultimate source of energy in most ecosystems?
The sun
