Practise Edexcel A-Level Biology graph skills through trend comments, quantitative graph evidence, tangent-rate calculations, error bars and line equations.
Coral reefs are one of the Earth's most diverse biological environments.
They are thought to cover of the planet.
It is estimated that by 2030,90% of coral reefs will have been damaged by anthropogenic activities.
The photographs show an undamaged coral reef in the Maldives and a damaged coral reef elsewhere.
Undamaged reef
Damaged reef
Another method being developed to restore damaged coral reefs uses 'reef carpets' (RC).
The diagram shows coral RCs.
Three types of coral were each grown on a RC.
The coral RCs were left on the seabed and monitored for 17 months.
The scientist developing this method monitored the health of the coral and the diversity of fish that were present on three types of coral, A, P and S.
The graph shows the diversity of fish present with these types of coral RCs.
Diversity of fish
State two conclusions that can be made about the diversity of fish on these three types of coral.
(2)
Exercise affects the cardiac output of a person.
The graph shows the change in heart rate following exercise for an unfit person and for a fit person.
Calculate the heart rate of the unfit person at 5 minutes.
The change in heart rate of the unfit person is a linear relationship.
Use the equation for a straight line y=mx+c.
Glaciers are decreasing in height and retreating due to global warming. The diagram shows a retreating glacier.
The graph shows the decrease in height of a glacier from 1980 to 2000.
Calculate the mean drop in height from 1980 to 2000. Give suitable units for your answer.