Estimating population size and distribution using transects: practical | Exit Quiz | Oak National Academy

A straight line between two points that is used to take measurements and observations is called a ___.

Answer explanation

A straight line between two points that is used to take measurements and observations is called a transect.

Which of the following are abiotic factors that could be measured in a meadow while sampling an organism?

• The number of plants in a quadrat.

• The pH of the soil.

• The wind speed.

• How many insects are found on the species being sampled.

Answer explanation

Wind speed and soil pH are abiotic factors that could be measured in a meadow.

Match the words with their definitions.

• distribution

• The number of a species that is found within a habitat.

• biodiversity

• The range of different species found within a habitat.

• abundance

• The geographical area in which a species can be found.

Answer explanation

Abundance is the number of a species in a habitat; biodiversity is the range of different species found in a habitat; and distribution is the geographical area in which a species can be found.

An example of systematic sampling is ...

• when you randomly put a quadrat on the ground when sampling.

• when you throw a quadrat to randomly sample an area with a quadrat.

• when you place a quadrat at regular intervals along a transect to sample.

• when you randomly place a quadrat along a transect.

Answer explanation

An example of systematic sampling is when you place a quadrat at regular intervals along a transect to sample. Systematic sampling is not random but follows a system or set of rules to sample organisms. You should *never* throw a quadrat.

What might happen to the abundance of plant species along a transect as you leave the shade of a tall Oak tree?

• The abundance of plants will not change.

• The abundance of plants will increase.

• The abundance of plants will decrease.

• There will be no plants in the shade under the tree.

Answer explanation

The abundance of plant species will increase as there is more light as you leave the shade of the Oak tree. More plants will be able to use this increased light intensity to grow.

Why might scientists want to place quadrats along a transect to observe and measure a species?

• To work out if a species is becoming extinct.

• To look at changes in the food chain diagram.

• To look at changes in the abundance of a species.

• To measure the mean number of species in an area.

Answer explanation

Scientists might want to place quadrats along a transect to observe and measure a species, to look at how different abiotic factors change the abundance of a species.