| What are Biotic factors? | Factors that can affect an organism's occurrence, population, or distribution in an ecosystem, that are the result of the effect of other living organisms. E.g
Predation, competition, grazing, disease. |
| What are Abiotic factors? | Factors that can affect an organism's occurrence, population, or distribution in an ecosystem, that are the result of the effect of non-living factors such as temperature, light exposure, pH, wind exposure, soil: moisture, temperature, oxygen and nutrient availability. |
| Numbers of a species. | Population |
| Different species sharing and interacting within a specific ecosystem, | Community |
| Ecological competition within members of the same species. | Intraspecific competition |
| Ecological competition between members of different species. | Interspecific competition |
| Why are changing bacterial populations expressed using logarithms? | To enable massive population changes to be presented graphically. |
| What general name is given to factors that may determine the size of any population? | Limiting factors |
| Why is temperature such a key limiting factor determining population size? | All life processes are enzyme-dependent, with temperature affecting the rate of enzyme-controlled reactions. |
| Why is light intensity such a key limiting factor determining population size? | With green plant producers dependent on light intensity for photosynthesis. |
| What word describes the number of individuals of a species in a given space? | Abundance |
| Investigating species distribution involves random sampling. Why is random sampling important to collect reliable data? | Ensures that there is no bias |
| An alternative method using a Belt Transect is more useful when investigating a linear change across an area. What type of sampling is this? | Systematic Sampling |
| What is meant by an Ecological Succession? | Gradual changes to species populations in an area over time and space |
| Mark-release-recapture is a technique used to study motile animal populations. State the formula used to estimate population size using this technique. | The total number of individuals in sample 1 times the total number of individuals in sample 2 divided by the number of marked individuals recaptured. |
| What is important about the marking method used for this? | The marking method is not toxic;
It doesn't make the marked individual more conspicuous e.g. for predation;
The mark or label is not lost or rubbed off during the investigation. |
| What is the meant by the "Pioneer species" in ecological succession? | The first species to colonise. |
| What tends to happen to the environment as a succession proceeds? | The newly established species make the environment less harsh so that other new species can colonise. |
| What is the final, stable community in a succession called? | Climax Community |
| "The active, practical intervention strategies necessary to maintain and sustain ecosystems and biodiversity" What does this describe? | Conservation |
