Ecology
What is a population?
Total number of a species in a habitat
If prey numbers fall, what would you predict to happen to predator numbers?
Also fall due to lack of prey (food)
What instrument is used to measure light intensity?
Light meter
Name a sampling technique
Quadrat, netting, tree beating, pitfall trap
What is shown in the pyramid of numbers?
The number of organisms at each step in a food chain
What is biodiversity?
The variety and abundance of organisms in an ecosystem
What is a producer?
An organism that produces its own food (typically a plant)
Give an example of 2 abiotic factors
temperature, light intensity, pH, moisture
What would be used to sample soil pH?
Soil pH meter
What are 3 ways energy is lost from a food chain?
Organisms that can reproduce to produce fertile offspring
What do the arrows in a food chain show?
The flow of energy
Give a biotic factor
grazing, disease, predation, competition, food availability
What the error that can occur with measuring soil pH?
Give one example of an irregular pyramid of numbers
tree or parasites
What is a community?
All the living organisms that live within a habitat
What is meant by an organisms niche?
The role of the organism in the community (it includes its interactions with other organisms and the conditions that it needs to survive)
lichen, mayfly nymph, water louse, ....
How could you increase the reliability of using a quadrat?
Do multiple samples, use a transect line to reduce human bias
True or False. Pyramid of energy is always a regular shape
True
What is an ecosystem?
The community of organisms living in a habitat and the non-living components with which they interact
Give 2 things that could part of an organisms niche?
food/resources required, predation, competition, light availability, nutrients, temperature
What is an indicator species?
A species whose presence of absence indicates pollution/environmental quality
What is one error associated with pitfall traps and how to minimise
2. Cup need to stay level with the ground so that all species are sampled
3. Traps need to be checked regularly to stop insects eating each other
4. Trap needs to be camouflaged to stop other organisms eating the insects
A food chain starts with grass (10,000 J) which is eaten by rabbits. The rabbits are eaten by eagles. How much energy do the eagles get?
100 J