exam questions Flashcards
1
Q
explain the importance of sampling in measuring the biodiversity of a habitat (2 marks)
A
- difficult to count every individual
- sample provides an estimate
- sample is representative of a whole area
2
Q
explain the difference between species richness and evenness and why both are needed to assess biodiversity (3 marks)
A
richness = number of different species in a habitat
evenness = number of individuals of each species in a habitat
- both reveal dominance
- high biodiversity is associated with both
3
Q
outline 3 reasons of importance in conserving a species
A
- part of a food chain - provide food or control a population
- duty of humans to care for others/ethics
- economic/tourism
4
Q
why is it sometimes necessary to conserve a species ex situ? (3 marks)
A
- due to climate change or human factors
- low population
- reproduction is difficult in the wild
- protection from pathogens
- maintain gene pool
5
Q
give 3 advantages of storing plants as seeds
A
- takes up little space
- less vulnerable to disease
- more viable
6
Q
outline the implications for a habitat if simpsons index is low (2 marks)
A
- habitat dominated by few species
- ecosystem is unstable
7
Q
how can simpsons index be made more accurate? (2 marks)
A
- random sampling
- standardised procedure
- survey at different times
8
Q
define biodiversity
A
- variety of species in an area
- variety of ecosystems
- variety of alleles
