Biology Mrs J- Start July

Question 1

What is the definition of a population?

Answer 1

All the organisms of one species in a particular area at one time, that can potentially interbreed.

Question 2

What is the definition of a community ?

Answer 2

All organisms of all species within a given area at the same time.

Question 3

What is the definition of a habitat?

Answer 3

Where an organism lives

Question 4

What is the definition of an ecosystem?

Answer 4

All organisms and interactions with the abiotic factors.

Question 5

What is the definition of a niche?

Answer 5

Where an organism lives and the specific role it has

Question 6

What is the definition of biotic and abiotic factors?

Answer 6

Biotic = living factors E.g organisms
Abiotic= non-living factors E.g PH, Temp ect.

Question 7

What is the competitive inclusion principle?

Answer 7

When 2 organisms try and occupy the same Niche, the best adapted will survive, and the other will die out

Question 8

What is the definition of species richness?

Answer 8

The number of different species

Question 9

What is the definition of species diversity?

Answer 9

The number of different species and the number of organisms within each of these species.

Question 10

What is the definition of carrying capacity?

Answer 10

The maximum size of a population that can be supported by an area

Question 11

What is the carrying capacity affected by?

Answer 11

• abiotic factors (NL)
• and interactions between biotic factors

Question 12

What are some examples of biotic factors that could affect the carrying capacity?

Answer 12

• Competition for resources
• Intraspecific predation
  -Interspecific predation

Question 13

What is intraspecific predation?

Answer 13

Within species predation e.g canabalism

Question 14

What is interspecific predation?

Answer 14

Between species E.g lynx eats the rabbit

Question 15

For the previous example: if the rabbit population were to increase, would the lynx population increase or decrease?

Answer 15

The lynx population would also increase

Question 16

What technique would I use for sampling non-motile organisms?

Answer 16

Quadrats!

Question 17

What are the key elements/steps to using a quadrat?

Answer 17

1. Tapes at right angles
2. Random no. generator to get random coordinates
3. Place quadrat at coordinate
4. Count number of organisms within quadrat/ use percentage cover of each square
5. Repeat 20x minimum
6. Calculate the mean from all data collected for each repeated quadrat
7. Use the calculation to give an estimate for the target area.

Question 18

What is the calculation used to estimate the total population size of a target area when using a quadrat?

Answer 18

(Total area m^2 / area of quadrat m^2) x mean no. Of organisms per quadrat x mean no.
per quadrat

Question 19

What 2 things must I control when using a quadrat?

Answer 19

1. Same sized quadrat
2. Same specific time of year

Question 20

How would I measure the distribution of organisms?

Answer 20

By using a transect

Question 21

What is the benefit of using % cover instead of counting each organism?

Answer 21

It is less time consuming, so more efficient

Question 22

What must I also measure when using transects?

Answer 22

Abiotic Factors (PH/Temp)

Question 23

What technique should I use to estimate the population size of motile organisms?

Answer 23

Capture, Mark, Re-capture

Question 24

I hat are the steps in this technique? (5 steps)

Answer 24

1. For fixed time collect species in a specific location
2. Mark them so not to disadvantage them I.E not easily identifiable to predators!
3. Release them and give them time to mix
4. Collect a second time- over the exact same time period and the same time of day.
   Then note down the total number collected. (Ones already marked have been re-captured)
5. Use the estimate equation:
   (N1 x N2 ) / N3

Question 25

What do the elements of the final equation for CMRC represent?

Answer 25

N1= total no. Caught first time
N2 = total no. Caught 2nd time
N3 = no that were already marked on the 2nd time capture.