HARD
AS and A Level
IMPORTANT
Earn 100

Five 0.25 m2 quadrats were placed randomly in an area of grassland in the UK. The percentage of each quadrat occupied by each species of plant was estimated to the nearest 5% and recorded in the table.Question Image

Explain why the percentage cover for all the species in each quadrat adds up to more than 100%.

Important Questions on Classification Biodiversity and Conversation

HARD
AS and A Level
IMPORTANT

Five 0.25 m2 quadrats were placed randomly in an area of grassland in the UK. The percentage of each quadrant occupied by each species of plant was estimated to the nearest 5% and recorded in the table.Question Image

Suggest why the percentage cover was recorded to the nearest 5%.

HARD
AS and A Level
IMPORTANT

Five 0.25 m2 quadrats were placed randomly in an area of grassland in the UK. The percentage of each quadrat occupied by each species of plant was estimated to the nearest 5% and recorded in the table.Question Image

Could these results are used to obtain a valid estimate of the species frequency for each species? Explain your answer.

HARD
AS and A Level
IMPORTANT

A sample of 39 ground beetles was captured from an area of waste ground measuring 100×25 metres. Each animal was marked and then released. A second sample was caught on the following day. Of these, 20 had been marked.
Use these results to estimate the number of ground beetles in the population. 

HARD
AS and A Level
IMPORTANT

A sample of 39 ground beetles was captured from an area of waste ground measuring 100×25 metres. Each animal was marked and then released. A second sample was caught on the following day. Of these, 20 had been marked. These results are used to estimate the number of ground beetles. State three assumptions that must be made in order to make this estimate. 

HARD
AS and A Level
IMPORTANT

Describe a method that you could use to check that the mark-release-recapture method gives a valid estimate of the ground beetle population in the area of waste ground.

HARD
AS and A Level
IMPORTANT

Light is an important abiotic factor that determines the distribution and abundance of plants. Some plants are adapted to grow in areas of low light intensity. They are known as shade plants. Some students investigated the abundance of Dog’s Mercury. Mercurialis perennis, under forest trees in eight different locations. At each location, they used ten randomly positioned quadrats to measure the percentage cover of this shade plant.
Question Image

Draw a scatter graph to see if there is a correlation between light intensity beneath the canopy and the abundance of M. perennis.

HARD
AS and A Level
IMPORTANT

Light is an important abiotic factor that determines the distribution and abundance of plants. Some plants are adapted to grow in areas of low light intensity. They are known as shade plants. Some students investigated the abundance of Dog’s Mercury. Mercurialis perennis, under forest trees in eight different locations. At each location, they used ten randomly positioned quadrats to measure the percentage cover of this shade plant.
Question Image

State a null hypothesis for this investigation.