B4: It's A Green World!

Front 1

Explain the problems Biologists find when they investigate where organisms live?

Back 1

- there are very many organisms
- they seem to live all over the place

Front 2

Explain how Biologists have overcome these problems?
Include the words DISTRIBUTION and POPULATION.

Back 2

To overcome problems, biologists have created some techniques to collect information about two things:
- DISTRIBUTION = they record the location of organisms of one species
- POPULATION = they then record the number of species of organisms of a particular species in one area.

Front 3

What is a COMMUNITY?

Back 3

Different populations live together in one area, and together they form a COMMUNITY .

Front 4

"Biologists look for ............. between the organisms in a community by studying how their distribution overlap"
Fill the blank.

Back 4

Relationships

Front 5

Biologists need techniques to collect information about organisms, to work out their distribution, population and community.
Describe these techniques.

Back 5

- collect organisms
- count the number of organisms in each species
- record where the organisms are found
- collect accurate data
- collect the data fairly
- collect reliable data

Front 6

Describe SAMPLING?

Back 6

SAMPLING is counting a small number of the total population and working out the total from the sample.

Front 7

Name the 5 sampling techniques.

Back 7

- quadrat
- transect lines
- nets
- pooters
- pitfall trap

Front 8

Describe how a QUADRAT can be used to estimate the population of a species.

Back 8

- square frame of a standard area, to define an area on the ground.
- the numbers of organisms of a particular species in the frame can be counted.

Front 9

Describe how TRANSECT LINES can be used to estimate the population of a species.

Back 9

- tapes that are laid across an environment
- you can count the organisms that touch the tape
E.G. plants on the ground
- quadrats can also be placed at regular intervals along the tape to record the DISTRIBUTION of organisms inside.

Front 10

Describe how POOTERS can be used to estimate the population of a species.

Back 10

- containers with a straw device used to suck in small animals, so they get can be identified and counted.

Front 11

Describe how PITFALL TRAPS can be used to estimate the population of a species.

Back 11

-small containers buried in the ground which collect small animals.

Front 12

Describe the "CAPTURE-RECAPTURE" method.

Back 12

1. capture a sample of organisms in an area, (first sample) count, mark and release them.
2. recapture and count a second sample of organisms in the same area at a later date.
3. count the total number of recaptured (previously marked) organisms in the second sample.

Front 13

What is the equation for working out the estimated population of the species?

Back 13

Number in first sample x number in second sample
____________________________________________________________
number in second sample previously marked

Front 14

How can you make sure a sample is accurate?

Back 14

Big enough sample:
- a small sample size is not very accurate
Being reliable:
- repeating readings will make the more accurate
Being fair:
- you should the same equipment
- use the same method each time
- make sure you randomly place equipment, so you do not have biased readings.