4.2 - Biodiversity

Question 1

What is biodiversity?

Answer 1

The spread of organisms and species in a particular habitat

Question 2

What is species evenness?

Answer 2

The proportion of each species there is in an area

Question 3

What is species richness?

Answer 3

How many different species there are in area

Question 4

What is a transect and why do you use it?

Answer 4

A line across a habitat used to measure the change of concentrations of species e.g. to investigate the influence of a factor

Question 5

How do you use a transect?

Answer 5

Take measurements every n metres down the line

Question 6

What is a quadrat and how do you use it?

Answer 6

A square grid - place in a location and count percentage cover of a species

Question 7

What are the sampling methods?

Answer 7

Random
Stratified
Systematic

Question 8

What is random sampling?

Answer 8

When you take a random number generator to get two coordinates along two axes.

Question 9

What is systematic sampling?

Answer 9

When you take measurements n metres along a transect

Question 10

What is stratified sampling?

Answer 10

When a habitat is divided into different areas e.g. wooded, grassy and samples are taken here

Question 11

What is simpsons biodiversity index?

Answer 11

A calculation done in order to establish the biodiversity of a habitat - the closer the number is to one, the higher the diversity

Question 12

Chi squared test?

Answer 12

Compared the expected number of species with the actual number e.g. to establish the decline or incline of birth rates

Question 13

What affects biodiversity?

Answer 13

Alter ecosystems
Destroy and fragments species
Pollute atmosphere
Agriculture

Question 14

What is extinction?

Answer 14

When the last living member of a species ceases to exist

Question 15

Why did this change?

Answer 15

Because many of the organisms in the kingdoms had both animal and plant characterised e.g. fungi and so could not be classified

Question 16

How do you sample animals?

Answer 16

Sweep net technique sweeps up small insects, overturn onto a white sheet

Question 17

What is opportunistic sampling?

Answer 17

When the quadrat is placed to give the largest population density

Question 18

Ecological reasons to maintain biodiversity?

Answer 18

The presence of a keystone species can cause the ecosystem to collapse if removed, also they can provide natural solutions to our problems

Question 19

Economic reasons to maintain biodiversity?

Answer 19

Retention and purification of fresh water
Medicine 
Recycling of nutrients
Recycling of waste
Natural resources

Question 20

Human aspects that threaten biodiversity?

Answer 20

Pollution
Exploitation of natural resources
Fragmentation of habitats
Alteration of ecosystems

Question 21

How does agriculture threaten biodiversity?

Answer 21

Over farming causes soil erosion
Removal of nutrients from soil
Monoculture
Fragmentation of habitats 
Pesticides/insecticides

Question 22

What is conservation in situ?

Answer 22

Maintenance of the biodiversity/ habitat/ species in its natural habitat

Question 23

Conservation ex situ?

Answer 23

Preservation of a species outside its natural habitat