Unit 3, topic 1.1: Biodiversity

Question 1

Biodiversity

Answer 1

The variety of living species on earth, including plants, animals, bacteria and fungi

Question 2

Types of biodiversity

Answer 2

Genetic, species and ecosystem diversity

Question 3

Genetic diversity

Answer 3

The number of different alleles possessed by a species, determined through analytical DNA techniques such as DNA sequencing and DNA profiling

Question 4

Species diversity

Answer 4

The number of different species present in an ecosystem: caused from evolution

Question 5

Measures of species diversity

Answer 5

Species richness and species evenness

Question 6

Species richness

Answer 6

Number of different species present in an ecosystem.

EQUATION:
S-1/logN

S= number of species present in the community
N= number of individuals in the community

Question 7

Species evenness

Answer 7

Relative abundance of individuals of each species within an ecosystem.

Question 8

Ecosystem diversity

Answer 8

Variations of ecosystems in a certain geographical location, in relation to the combined influences of biotic and abiotic factors

Question 9

Biomes

Answer 9

A group of ecosystems which have a similar climate and other conditions which extend over a large area

Question 10

Tolerance range

Answer 10

Set of environmental conditions within a species suitable survivable condition range

Question 11

Measures of biodiversity

Answer 11

Percentage cover, percentage frequency, Simpson’s diversity index, Lincoln’s diversity index

Question 12

Percentage cover

Answer 12

A measurement of the relative abundance of a species in a single area (the amount of the species covering a certain area)
Percentage cover can be calculated by estimating the percentage of each quadrat covered by any particular species: dividing quadrat into smaller units = more accurate

EQUATION:
%=(covered/total squares)*100

Question 13

Percentage frequency

Answer 13

A measure of the appearance of plant species within sample quadrats

The percentage frequency is the number of quadrats containing the species of interest divided by the number of quadrats sampled, expressed as a percentage

EQUATION:
% freq. = (total number of quadrats in which the species occured/ total number of quadrats studies)*100

Question 14

Simpson’s diversity index

Answer 14

Measure of diversity which takes into account the number of species present, as well as therelative abundanceof each species

EQUATION:
D = N(N-1)/∑n(n-1)

N= total number of organisms
n= number of organisms in each species

Question 15

Lincoln’s index

Answer 15

Measures population sizes of individual animal species based of the capture, mark, recapture method

EQUATION:
N = M*n/m

M = number of individuals tagged and released in the first sampling
n = number of individuals caught in the second sampling
m = number of tagged individuals caught in second sampling

Question 16

Species interactions

Answer 16

Species compete for resources, use each other as food and assist each other
→ can be positive, negative or neutral

Question 17

Intraspecific species interaction

Answer 17

interactions occurring within organisms of the same species

Question 18

Interspecific species interaction

Answer 18

interactions between individuals of different species

Question 19

Predation (predator → prey relationship)

Answer 19

A biological interaction where one organism kills and consumes the other (predator and prey)

Question 20

Competition

Answer 20

An interaction in which two organisms require a resource which is limited in supply (water, food, territory etc.)

Question 21

Symbiosis

Answer 21

A close, prolonged interaction/relationship between two organisms

Question 22

Types of symbiotic relationships

Answer 22

Commensalism, Mutualism, Parasitism, Neutralism, Competition & Predation

Question 23

Commensalism

Answer 23

where one species benefits while the other is unaffected

Question 24

Mutualism

Answer 24

both species benefit

Question 25

Parasitism

Answer 25

One species benefits while one is harmed

Question 26

Neutralism

Answer 26

both species unaffected

Question 27

Abiotic factors influencing biodiversity

Answer 27

climate, substrate/soil, size/depth of area

Question 28

Climate (AF influencing BD)

Answer 28

Number of factors including precipitation, temperature, wind direction, cloud cover and sunshine.

Affect the type and abundance of species present, e.g. desert climates with little rainfall means plant growth is slow and therefore herbivorous animals are scarce

Question 29

Substrate/Soil (AF influencing BD)

Answer 29

Number of factors include thickness, structure/porosity, PH, nutrient content and salinity.

Factors influence type of soil present and therefore vegetation and formation of food chain: consumers, habitat growth

Question 30

Size/depth of area (AF influencing BD)

Answer 30

Small areas reduce biodiversity due to competition for resources, genetic diversity lower due to smaller population sizes.

Aquatic area factors: light, depth, turbidity, oxygenation, temperature, water flow