B4.1/2 - Sampling Techniques & Identifying organisms

Question 1

Define population

Answer 1

The number of organisms of a particular species that lives in an area

Question 2

Define community

Answer 2

Different populations that live together in one area form a community.

Question 3

What is a sampling technique?

Answer 3

A sampling technique is when scientists count a small number of the total population, and work out the total from this sample.

Question 4

Name 5 sampling techniques

Answer 4

• Quadrats
• Transect lines
• Nets
• Pooters
• Pitfall traps

Question 5

Explain what the capture-recapture method is

Answer 5

This method is when you capture a small sample of organisms in an area, count them, mark them (paint usually) and then release them. Recapture another small sample from the same area and count them, including counting the recaptured ones (marked ones). From this you can figure out the estimate total population of the species.

Question 6

What equation can be used to estimate population size?

Answer 6

   number in second sample previously marked

Question 7

What do biologists assume when using the capture-recapture method?

Answer 7

When using this method biologists must assume that no death, emigration or immigration has occurred within the population. They also make sure that the same sampling method is used each time and that the marking technique does not effect the organisms survival. This ensure the estimate calculation is as accurate as possible.

Question 8

How to biologists make sure that their sampling is accurate?

Answer 8

• They must use a big enough sample
• They must make it a fair investigation
• They must make sure the data is reliable (multiple data recordings)

Question 9

Define habitat

Answer 9

A habitat is the natural home or environment of an animal, plant, or other organism.

Question 10

Name the two types of keys scientists use to identify organisms?

Answer 10

• Spider keys

- Number keys

Question 11

Define ecosystem

Answer 11

An ecosystem is a biological community of interacting organisms and their physical environment (habitat).

Question 12

Define biodiveristy

Answer 12

Biodiversity is the variety of plant and animal life in a particular habitat.

Question 13

Define zonation

Answer 13

Zonation is the gradual change in population of organisms in a community.