Adaptations of Organisms

Question 1

1. What is adaptation?

Answer 1

Adaptation is how all species have features which allow them to survive in the environment in which they are normally found

Question 2

2. What are the 3 types of adaptation?

Answer 2

1. Morphological/physical eg thick white fur of the polar bear 2. Behavioural eg how it stalks its prey and smashes through ice to locate it 3. Physiological/biochemical_eg. the lowering of its metabolic rate when food is scarce to conserve energy

Question 3

3. What are the 3 types of ecological factors that influence the distribution of organisms?

Answer 3

• Climatic * Edaphic * Biotic

Question 4

4. List the main climatic factors

Answer 4

Temperature, water availability, light intensity and quality and day length

Question 5

6. List the main biotic factors

Answer 5

These are the factors due to other living organisms: competition (interspecific - between different species and intraspecific - within the same species), predator-prey relationships and accumulation of waste

Question 5

5. List the main edaphic factors

Answer 5

These are soil factors: PH, availability of nutrients, water content and oxygen content (aeration)

Question 6

7. What is an organism’s ecological niche?

Answer 6

The organism’s role in the environment including its role in the food chain, its abiotic requirements and its biotic relationships

Question 7

8. What is the purpose of sampling when investigating organisms present in an area?

Answer 7

Habitats are normally too large to be able to count the numbers of all the different species present

Question 8

9. Why do we randomly sample in biology?

Answer 8

In a habitat which is uniform OR has no clear pattern, it: * Avoids bias * Ensures sample is representative

Question 9

10. How do we estimate the amount or abundance of organisms present?

Answer 9

• Density - count numbers using a quadrat (gives numbers per unit area) * % cover - gives estimation of % area in a quadrat covered by a plant species (round up to nearest 10%) * Frequency - at each sampling point, record a species as being present or absent

Question 10

11. When would systematic sampling be used and what does it involve?

Answer 10

• Used when there appears to be zonation/clear transitions from one habitat to another * Sampling is carried out along a line or transect - either continually or at intervals

Question 11

12. What is a belt transect?

Answer 11

Sampling occurs along a transect line using quadrats

Question 12

13. What is an interrupted belt transect?

Answer 12

Same as belt transect but it is over a long distance so the sampling is done at intervals