# B2.4 Organisms and their environment Flashcards Preview

## Biology: B2 > B2.4 Organisms and their environment > Flashcards

Flashcards in B2.4 Organisms and their environment Deck (14)
1
Q

What physical factors may affect an organism?

A

Temperature, availability of nutrients, amount of light, availability of water and availability of oxygen and carbon dioxide

2
Q

A

A square frame enclosing a known area e.g. 1m squared

3
Q

What is the first step for collecting a random sample with a quadrat?

A

Place a quadrat on the ground at a random point within the first sample area. You could divide the area into a grid and use a random number generator to pick which square you place it in

4
Q

How do you work out population size?

A

You work out the mean number of the organism in one quadrat then times it by the total area to get the population of the entire sample area

5
Q

What is the first step for collecting a random sample with a transect line?

A

Mark out a line in the area you want to study using a tape measure

6
Q

How do you make your results more reliable?

A

Take a large sample size, use random samples

7
Q

How do you make your results valid?

A

Control all the variables, this way you can see whether it is an environmental factor affecting distribution

8
Q

What is the second step for collecting a random sample with a quadrat?

A

Count all the organisms within the quadrat

9
Q

What is the third step for collecting a random sample with a quadrat?

A

Repeat steps 1 and 2 as many times as possible

10
Q

What is the fourth step for collecting a random sample with a quadrat?

A

Work out the mean number of organisms per quadrat within the first sample area

11
Q

What is the fifth step for collecting a random sample with a quadrat?

A

Then repeat steps 1-4 in a different sample area

12
Q

What is the sixth step for collecting a random sample with a quadrat?

A

Then compare the data of the two different areas

13
Q

What is the second step for collecting a random sample with a transect line?

A

Collect data along the line. This is done by counting the number of the organisms you are interested in that touch the line

14
Q

What is the third step for collecting a random sample with a transect line?

A

Or you could use quadrats, placing them next to each other along the line at intervals