Estimating population size using quadrats: practical | Starter Quiz | Oak National Academy

True or false? A bottle garden is an example of an ecosystem.

• true

• false

Answer explanation

A bottle garden is an example of an ecosystem as it is made up of living organisms and the organisms within the bottle garden interact with each other and their non-living surroundings, e.g. soil type, moisture and temperature.

What is this piece of equipment called?

Answer explanation

This piece of equipment is called a quadrat and is used to sample populations.

Which of the following populations of organisms might you use a quadrat to sample?

• 
• 
• 
• 

Answer explanation

Dandelion plants and other plants can be sampled using a quadrat. This is because they grow in one place. Starfish could also be sampled using a quadrat as although they move, they only move slowly so you are able to count the starfish easily.

The diagram shows a pitfall trap. Which of the following organisms might be sampled using this piece of equipment?

• 
• 
• 
• 

Answer explanation

Beetles are a common group of organisms that are sampled using a pitfall trap. Ground beetles are often too heavy to fly, so once they fall into the trap they are not able to get out.

Rainfall in a habitat is an example of ...

• both a biotic and an abiotic factor.

• a biotic factor.

• an abiotic factor.

Answer explanation

Rainfall in a habitat is a non-living or abiotic factor.

When carrying out a mark-release-recapture experiment we put a small mark on the organism so that we know it has been captured before. What is important to remember when marking an organism?

• To make sure that the mark stands out so it is easy to count.

• To use a substance that is harmless to the organism.

• To make sure that the mark is large.

• To make the organism stand out to a predator.

Answer explanation

When we mark an organism, we need to make sure that it does not harm the organism. If the mark stands out it may attract the attention of predators, so marks should be small, not easy to see and be harmless to the organism.