Required Practical: Ecosystems (OCR GCSE Biology A (Gateway Science Suite)): Flashcards
📚Flashcards
Practise the cards
13 cards from this deck
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Practise the cards
13 cards from this deck
Transect definition
Transect definition
A straight line along which measurements are taken at regular intervals to study habitat changes
Quadrat definition & typical size
Quadrat definition & typical size
Square frame (usually 1m x 1m) to isolate a sample area for study
Distribution definition
Distribution definition
The way organisms are spread across an area
Abundance definition
Abundance definition
Number of individuals of a species in a given area
Purpose of using transects
Purpose of using transects
To study how distribution of organisms changes across a habitat
Purpose of using quadrats
Purpose of using quadrats
To estimate population size/abundance in a specific area
Interval for placing quadrats on transect (example)
Interval for placing quadrats on transect (example)
Every 2 metres (regular intervals)
Why place quadrats randomly?
Why place quadrats randomly?
To avoid bias in sampling
How to estimate total population from quadrat data
How to estimate total population from quadrat data
Calculate mean per quadrat, then scale up to entire area
Why take multiple quadrat samples?
Why take multiple quadrat samples?
To make data reliable and get an accurate average
Mean in ecological data
Mean in ecological data
Average number of organisms per quadrat
Mode in ecological data
Mode in ecological data
Most common number of organisms found in quadrats
Median in ecological data
Median in ecological data
Middle value when organism numbers arranged in order