AQA A Level Biology Section 7.4 Ecology

The number of individuals of one species is:

• a community

• a population

• a niche

• an ecosystem

All the populations in a habitat is:

• an ecosystem

• a niche

• a community

• a succession

The living factors which affect populations sizes are ___________ factors

The non-living/physical factors which affect a population size are ____________ factors

What is indicated by the yellow line on the graph?

Which of the following are abiotic factors?

• temperature

• soil pH

• predation

• light intensity

Which of the following are biotic factors?

• competition

• salinity

• predation

• carbon dioxide concentration

Using a grid with coordinates to place quadrats is an example of:

• random sampling

• systematic sampling

Using a transect to place quadrats is an example of:

• systematic sampling

• random sampling

Which is the correct formula for estimating populations using the mark-release-recapture method?

• $\frac{number\ in\ 1st\ sample\ \ x\ \ number\ in\ 2nd\ sample}{number\ recaptured\ \left(marked\right)\ in\ 2nd\ sample}$

• $\frac{number\ recaptured\ \left(marked\right)\ \ x\ \ number\ in\ 2nd\ sample}{number\ in\ 1st\ sample}$

• $\frac{number\ recpatured\ \left(marked\right)\ \ x\ \ number\ in\ 1st\ sample}{number\ in\ 2nd\ sample}$