2.2' Flashcards
What does interaction of species lead to
Result in energy and nutrient flows
What factors play a significant role in the flow of energy in communities?
Photosynthesis and respiration
Define a community
A group of populations living and interacting with each other in a common habitat
What is an ecosystem
An ecosystem is a community and the physical environment with which it interacts
What is respiration?
The conversion of organic matter into carbon dioxide and water in all living organisms, releasing energy.
Aerobic respiration formula
Glucose + oxygen = carbon dioxide + water
What is dissipated during respiration?
Large amounts of heat, increasing the entropy in the ecosystem while enabling organisms to maintain relatively Low entropy and so high Organization
What does photosynthesis produce
glucose and oxygen
What is a tropic level
The position that an organism occupies in a food chain, or the position of a group of organisms in a community that occupy the same position in food chains
How is energy lost throughout trophic levels?
Through heat,
What is a producer?
plants or algae that produce their own food using photosynthesis and form the first trophic level in a food chain
What are the different pyramids
Number, biomass and productivity pyramids
What is the second law of thermodynamics?
Tendency for numbers and quantities of biomass and energy to decrease along the food chain.
What is bioaccumulation?
The build-up of persistent or biodegradable pollutants within an organism or trophic level because they cannot be broken down.
What is biomagnification?
Increase in concentration of persistent pollutant throughout the food chain.
Give examples of toxins that can bioaccumulate.
DDT and Merucry
What is a pyramid of biomass measured in?
Grams of biomass per square m
What do biomass pyramids show?
Greater quantities at higher trophic levels because they represent the biomass present at a fixed point in time.
What do Productivity pyramids show?
Refer to the flow of energy through a trophic level, indicating the rate at which stock/storage is being generated.
What is an autotroph?
An organism that makes its own food - a producer
What do pyramids show?
They are graphical models that show the quantitative difference that exist between the trophic levels of a single given area and time.
Where do pesticides accumulate?
They accumulate in body fat hence they don’t break down.
