Distribution of Organisms Flashcards
Why do different organisms live in different places?
Because the environment varies. Different organisms are adapted to living in specific environments/habitats.
What is a habitat?
A place in which an organism lives.
What is the distribution of an organism?
Where the organism is found/lives.
Which environmental factors affect the distribution of an organism?
- Temperature
- Water supply
- Availability of Oxygen and Carbon-Dioxide
- Availability of Nutrients
- Availability of Light
An organism might be more common in one area than another due to _________
Environmental differences.
How can you measure the distribution of organisms? Give 2 methods.
- Transect line - study how the distibution changes along a line
- Quadrats - study how the distribution varies in an area
How to use a Quadrat?
1) Place the quadrat on the ground at a RANDOM point. Split the area you’ve chosen to study into a grid and use a random generator to generate co-ordinates.
2) Count the organisms within that quadrat.
3) Repeat these steps with as many quadrats as you like.
How to use a Transect?
1) Mark out the line you want to measure the organismal distribution of and place the transect along this line.
2) Measure the distribution by counting the organisms that touch the line, or place quadrats at regular intervals along the transect line.
How can you make sure your results are reliable if you’re investigating the distribution of an organism?
Use a larger sample size, this means your results are more representative, therefore they’re more reproducible because they represent a larger proportion of the population.
How can you make sure your results are valid if you’re investigating the distribution of an organism?
- Must be reliable and must answer the original question.
- Control all the variables
- Random points for quadrats
