11 - Biodiversity

Question 1

importance of biodiversity

Answer 1

• it is essential in maintaining a balanced ecosystem
• all species are interconnected. tress provide shelter for animals, animals eat plates
• we rely on balanced ecosystems as they provide us with food, oxygen and materials to survive

Question 2

ways to study biodiversity

Answer 2

• habitat
• species
• genetic

Question 3

Habitat biodiversity

Answer 3

• the number of different habitats found within an are
• each habitat supports a different number of species
• so the greater the habitat biodiversity, the greater the species biodiversity

Question 4

Species diversity

Answer 4

species richness
-> the number of different species living in a particular area

species evenness
-> a comparison of the number of individuals of each species living in a community

Question 5

Genetic biodiversity

Answer 5

• variety of genes that make up a species
• greater genetic biodiversity within a species allows for better adaptation to a changing environment so more likely to survive

Question 6

Random sampling

Answer 6

selecting individuals by chance
- each individual in the population has an equal likelihood of selection
- random number computers

Question 7

Non-random sampling

Answer 7

• opportunistic
• stratified
• systematic

Question 8

opportunistic sampling

Answer 8

• non-random
• uses organism that are conveniently available

Question 9

stratified

Answer 9

• non-random
• population is divided into a number of strata
• a random sample is then taken from each of these strata proportional to its size

Question 10

systematic sampling

Answer 10

• different areas in a habitat are identifies and sampled separately
• e.g line or a belt transect

Question 11

reliability of sampling

Answer 11

Sampling bias
-> selection process may be biased. sampling bias can be reduced by random sampling

Chance
-> organism selected may not be representative of the whole population. Chance sample may include the 5 longest in the habitat
-> the greater the sample, the lower the probability that chance will influence the result

Question 12

sampling animals

Answer 12

• pooter
• sweep nets
• pitfall traps
• tree beating
• kick sampling

Question 13

pooter

Answer 13

• used to catch small insect
• sucking on a mouthpiece, insects are drawn into a holding chamber

Question 14

sweep nets

Answer 14

nets used to catch insects in areas of long grass

Question 15

pitfall traps

Answer 15

used to catch small, crawling invertebrates
- a hole is dug in the ground that the insects fall into
- must be deep enough so they cant fall out
- cover is used to stop rain

Question 16

tree beating

Answer 16

• used to take samples living in a tree of bush
• white cloth is layed underneath, and the tree is shaken

Question 17

kick sampling