Species and taxonomy

Question 1

How is the index of diversity calculated?

Answer 1

d= N(N-1)/ sum of n(n-1)

N= total number of individuals
n= number of individuals for that species

Question 2

What’s meant by species richness?

Answer 2

the number of different species in a community. It can be used to measure biodiversity, although doesn’t measure number of individuals in each species

Question 3

State reasons for preserving woodland

Answer 3

• protects habitats
• protecting endangered species
• maintains/ increases biodiversity
• reduces global warming/ greenhouse effect
• takes up carbon dioxide
• source of medicines/ chemicals
• reduces erosion or eutrophication

Question 4

Suggest 2 ways to measure biodiversity

Answer 4

• Species richness
• Index of diversity

Question 5

Suggest what impact hedgerow removal could have on insect biodiversity on the farm

Answer 5

• reduces variety of plant species
• reduces variety of habitats
• reduces variety of food sources
• reduces variety of animal species

Question 6

Define species

Answer 6

Individuals that can interbreed to produce fertile offspring

Question 7

Name the hierarchical taxonomic ranks used in the classification of species

Answer 7

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 8

What’s the naming system used in biological classification called?

Answer 8

Binomial system
The genus is first and species second.
The genus has a capital letter and species has a lower case letter to start.

Question 9

Why can courtship behaviour be used to classify species?

Answer 9

Members of the same species show the same courtship behaviour. The more closely related the species, the more similar the courtship behaviour.

Question 10

Suggest an impact of using pesticides on biodiversity on a farm

Answer 10

Kills pests which eat crops, reducing variety of animal species
Predators which eat the pest, leave/ die so further decrease in animal diversity

Question 11

Suggest an impact of using herbicides on biodiversity on a farm

Answer 11

Kills weeds so reduces variety of plant species
reduces variety of habitats
reduces variety of food sources
reduces variety of animal species

Question 12

Suggest the impact of monoculture on the biodiversity on a farm

Answer 12

A single species of plant in one field so reduces plant biodiversity
less variety of food sources and habitats for animals

Question 13

Whats meant by biodiversity?

Answer 13

its the variety of living organisms in an area

Question 14

Which biochemicals can be compared to determine evolutionary relationships?

Answer 14

DNA base sequences/ mRNA base sequences of the same gene
Amino acid sequences of the same protein

Question 15

What is courtship behaviour?

Answer 15

its carried out by organisms to attract a mate of the same species

Question 16

Describe the ways in which courtship behaviour makes organisms more likely to mate successfully

Answer 16

It can help organisms recognise members of their own species and a mate of the opposite sex. It can also stimulate the release of gametes or indicate fertility and sexual maturity.

Question 17

Define population

Answer 17

all the individuals of the same species that live in the same area at the same time and can potentially interbreed

Question 18

Explain what’s meant by a (phylogenetic) hierarchy (2)

Answer 18

• smaller groups within larger groups
• there’s no overlap between groups
• organisms are grouped based on their evolutionary relationships

Question 19

Define community

Answer 19

all the populations of all the species in a habitat

Question 20

Define habitat

Answer 20

the area where an organism lives

Question 21

Why must a large sample be collected?

Answer 21

ensure a representative sample

Question 22

Why must a sample be randomly selected?

Answer 22

to avoid bias

Question 23

What does standard deviation show?

Answer 23

the spread/ variation of the data from the mean

Question 24

How can random samples be obtained?

Answer 24

they can be obtained using a random number table

Question 25

Suggest reasons why genetic diversity may be low in a population

Answer 25

• Inbreeding
• Small population