Biodiversity

Question 1

species biodiversity

Answer 1

a product of two variables, the number of species and richness

Question 2

genetic diversity

Answer 2

the range of genetic material present in a gene pool or population of a species

Question 3

habitat diversity

Answer 3

the range of different habitats per unit area in a particular ecosystem

Question 4

advantages of habitats with good biodiversity

Answer 4

• resilience and stability due to range of plants
• genetic diversity so resistance to diseases
• some plants have deep roots so can cycle nutrients

Question 5

disadvantages of habitats with high biodiversity

Answer 5

• can result in fragmentation of a habitat
• managing grazing can be difficult as plant species have different requirements

Question 6

hotspots

Answer 6

• regions with higher biodiversity than others
• tend to be nearer tropics because there are fewer limiting factors
• threatened with 70% lost
• contains more than 1500 endemic species

Question 7

how new species form

Answer 7

• each species is individual due to their set of inherited genes
• each will be slightly differently adapted
• resources are limited creating competition
• species evolve to give them advantagef

Question 8

factors that affect evolution

Answer 8

physical borders - split gene pool by distancing them from each other

land bridges - allows species to invade new areas

Question 9

background extinction rate

Answer 9

the natural extinction rate of all species

Question 10

current extinction rate

Answer 10

• 100 species per million species per year
• current rate is 1000 times the background rate
• rate is far greater in hotspots

Question 11

total world biodiversity

Answer 11

• 7 million species alive today
• 2/3’s are in tropics
• 50% of tropical rainforests have been cleared by humans

Question 12

factors that maintain biodiversity

Answer 12

complexity of the ecosystem - more complex a food web, the more resilient it is

stages of succession - species diversity increase with time

Question 13

what makes a species prone to extinction

Answer 13

• narrow geographic range
• small population size
• low population density
• specialised feeders

Question 14

values of biodiversity

Answer 14

food sources - we eat other species and plants

natural products - medicines and fertilisers are derived from plants and animals

Question 15

conservation organisations

Answer 15

organisations that work to conserve or preserve biodiversity

Question 16

intergovernmental organisation

Answer 16

group of member states

Question 17

governmental organisation

Answer 17

• part of government
• autocratic

Question 18

non governmental organisation

Answer 18

• not part of government
• not for profit
• may be international or loca

Question 19

species based conservation

Answer 19

focused on conserving species but not habitats