Populations Flashcards
Define: Population
All the organisms of one species living in an area
Define: Habitat
The place where an organism lives
Define: Community
All the organisms/species living in an area
Define: Abiotic
The non-living features of an ecosystem
Define: Biotic
The living features of an ecosystem
Define: Niche
The role of a species in its habitat
What are the types of sampling?
- Random (quadrats)
- Systematic (transects)
What are the two types of quadrat?
- Square quadrat
- Point quadrat
How can abundance be measured?
- Frequency
- Percentage cover
How can population size of an animal be estimated?
Mark-release-recapture method:
- Capture sample & mark
- Take second sample
- Use the equation
What are the assumptions/considerations when doing the mark-release-recapture method?
- No births or deaths
- No migration
- Mark doesn’t come off between samples
- Marking doesn’t affect predation
- Proportion of marked:unmarked in second sample is representative of the whole population
- The marked organisms has enough time to distribute evenly throughout the population
What are the factors affecting the size of a population?
- Competition
- Predation
- Temperature
- pH
- Oxygen/carbon dioxide concentrations
- Humidity/water levels
- Light intensity
Define: Birth rate
Number of live births per 1000 per year
Define: Death rate
Number of deaths per 1000 per year
What does the demographic transition model look like? (DTM)
Stage 1:
High birth rate
High death rate
Stage 2/3:
High birth rate
Low death rate
Stage 4:
Low birth rate
Low death rate
Stage 5:
Low birth rate
Low death rate
