biodiversity

Question 1

define biodiversity

Answer 1

refers to variety and complexity of life

indicator in study of habitats

Question 2

define biodiversity hotspots

Answer 2

regions of that world that have a high biodiversity threatened by loss of biodiversity

Question 3

what are the reasons for maintaining biodiversity

Answer 3

ecological

economical

aesthetical

Question 4

what levels are biodiversity considered at

Answer 4

genetic

species

habitats

Question 5

what does every organism in an ecosystem have

Answer 5

niche

Question 5

define ecology

Answer 5

study of interactions between organisms

Question 6

give 4 examples of habitat biodiversity

Answer 6

woodlands

meadow

streams

sand dunes

Question 7

define community

Answer 7

population of all species in a habitat

Question 8

define population

Answer 8

number of organisms of each species

Question 9

how are species biodiversity measured by

Answer 9

species richness – number of species in an area

species evenness – relative abundance of species in an area

Question 10

what does habitat biodiversity refer to

Answer 10

number of different habitats found within an area

therefore, greater species biod. too

Question 11

what does species biodiversity refer to

Answer 11

richness and evenness

Question 12

what does genetic biodiversity refer to

Answer 12

variety of genes that make up a species

different alleles exist for a gene which leads to genetic biodiversity

higher genetic biod. allows a better adaptations to a changing environment

Question 13

define succession

Answer 13

process by which ecosystems change over time

Question 14

how does succession occur

Answer 14

changes to the environment causing plant and animal species present to change

Question 15

define primary succession

Answer 15

occurs on area of land newly formed or exposed (bare rock)

Question 16

define secondary succession

Answer 16

occurs on land where soil is present but contains no animal or plant species

Question 17

give examples of primary succession

Answer 17

volcano erupt

sand blown by wind

silt and mud

glaciers retreating

Question 18

describe the role of a pioneer species

Answer 18

arrive as spores/seeds carried by wind that colonise the bare (rock) environment

Question 19

give an example of a pioneer

Answer 19

lichen

stable symbiotic organism of fungi and algi

Question 20

what are the adaptations of pioneers

Answer 20

produce large quantities of seeds or spores

seeds that germinate rapidly

phototrophic

tolerant to extreme environments

fix nitrogen from the atmosphere
(adding the mineral content of the soil)

Question 21

what is humus

Answer 21

result of pioneers dying and decaying

their organic products release into the soil

Question 22

give an example of a secondary coloniser

Answer 22

moss

Question 23

give an example of a tertiary coloniser

Answer 23

plants (fern)

Question 24

what happens as you go through each seral stage

Answer 24

rock continues to be eroded and the mass of organic matter increases

Question 25

what happens to the soil as time goes by

Answer 25

contribute to a deeper and nutrient-rich soil, which retains more water makes abiotic conditions favourable for flowering plants, then trees when the soil is deep enough

Question 26

how do species succeed previous species in the intermediate community

Answer 26

different plant and animal spceis are better adapted to the current conditions in the ecosystem these species outcompete species previously present

Question 27

what is the final seral stage called

Answer 27

climax community stable state showing little change over time

Question 28

suggest why the climax community sometimes isn't the most biodiverse

Answer 28

dominant species out-competing pioneer and other species, leading to their elimination

Question 29

describe the lichen

Answer 29

xerophyte secretes acid which breaks down rock into soil

Question 30

define deflated succession

Answer 30

when succession is stopped artificially the final stage is called plagioclimax

Question 31

give examples that cause deflated succession

Answer 31

grazing of vegetation removing existing vegetation to plant crops

Question 32

why do we measure biodiversity

Answer 32

allows comparison between different areas and the same areas at different times

Question 33

what does a sample have to be

Answer 33

representative not over estimate biodiversity covers full range of species

Question 34

what does the sampling method depend on

Answer 34

accuracy sample size time of study and how long it's been investigated nature of organisms being sampled

Question 35

describe random sampling

Answer 35

where each individual in the population has an equal chance of selection mark out a grid using tape measures laid out perpendicular to each other use random coordinates and take a sample at each of the coordinates generated may not cover all areas of a land equally

Question 36

describe opportunistic sampling

Answer 36

selecting individuals that are available

Question 37

describe stratified sampling

Answer 37

number of samples in an area are proportional to its size followed by a random sample in the area

Question 38

describe systematic sampling

Answer 38

samples taken at fixed intervals used when an area is varied or when to look at change (using a belt or line transect)

Question 39

what are some limitations to sampling

Answer 39

- time of day - not identifying species correctly - not replicating

Question 40

how do we increase the reproducibility of a sample

Answer 40

use standard procedure sample many times then calculate the mean sample at different times/weather conditions`

Question 41

what qualitative technique can we use when using a line transect

Answer 41

ACFOR scale to measure species abundance

Question 42

what are some techniques to sample animals

Answer 42

sweep nets pooters tree beating pitfall traps

Question 43

define species richness

Answer 43

number of species in an area

Question 44

define species evenness

Answer 44

relative abundance of each species in an area

Question 45

what are issues with sampling

Answer 45

sampling bias chance

Question 46

what are examples of sampling animals

Answer 46

pooter sweep nets tree beating pitfall traps kick sampling (for rivers)