Chapter 10: Biodiversity Flashcards
What is meant by the term ‘taxon’?
A taxon is a grouping of organisms which share some basic features
What is meant by the term ‘species’?
A species is a group of similar organisms which can interbreed to produce fertile offspring
List the taxonomic groups in order.
Domain Kingdom Phylum Class Order Family Genus Species
What is classification?
Classification is the process of sorting a variety of items into manageable groups
What is the study of biological classification called?
The study of biological classification is called Taxonomy or Systematics
Why is a universally accepted system of classification important?
A universally accepted system of classification
1) allows scientists to communicate about an organism with the confidence that they are referring to the same thing
2) enables rapid access to info about a particular type of organism
3) makes it easier to identify and study organisms
What is the aim of classification in biology?
The aim of classification in biology is that it reflects the evolutionary relationships between organisms
Which taxon level is usually taken to be the basic taxon of a classification hierarchy?
The species is usually taken to be the basic taxon level/category for a classification hierarchy
What is a sub-species?
A sub-species is a further division of a species by the recognition of sufficient, subtle but consistent variation between members of that species
What is the evolutionary relationship between organisms called?
The evolutionary relationships between organisms is called phylogeny.
What is the bionmial nomenclature system and who invented it?
The binomial nomenclature system is the internationally accepted system of naming species and was developed by Linnaeus in the 18th century
Describe Linnaeus’s binomial system.
Each species has two Latin names. The first is the genus and always starts with a capital letter. The second is the particular species within that genus and always starts with a lower-case letter. Names are always written in italics or underlined if they are handwritten.
A group of related species form a ________?
A group of related species form a genus
What are the five kingdoms?
Prokaryotae Protoctista Fungi Plantae Animalia
What are the three domains?
Eukarya Bacteria Archaea
Closely related species diverged away from each other most recently. How is this shown on an evolutionary tree?
You can see this because their branches are close together.
How many levels of taxa are there?
There are 8 levels of taxa used to classify organisms.
Taxons are arranged in a hierarchy. What is meant by a hierarchy?
1) The largest groups are at the top and the smallest groups are at the bottom 2) Organisms can only belong to one group at each level in the hierarchy - there is no overlap
What is the plural for taxon?
The plural for taxon is taxa.
Brifely describe the structure of the phylogenetic hierarchy.
The phylogenetic hierarchy begins with the three domains. Closely related organisms in each domain are grouped into slightly smaller groups called kingdoms. Closely related organisms in each kingdom are grouped into phyla. Closely ralated organisms in each phyla are grouped into classes and so on…
Give one reason why the binominal system is useful.
The binominal system helps to avoid the confusion caused by using common names. For example over 100 species of plant are called raspberries.
What is artificial classification?
for later
What is natural classifcation?
for later
What are homologous characteristics?
for later
What are analogous characteristics?
for later
Species are placed in the same group based only on…
…shared homologous features and shared evolutionary history.
What is courtship behaviour?
Courtship behaviour is behaviour carried out by organisms to attract a mate of the right species
Courtship behaviour is species specific. What does this mean?
Only members of the same species will perform the behaviour and only members of the same species will respond to the behaviour
Why is courtship behaviour species-specific?
Courtship behaviour is species-specific
1) to allow members of the same species to recognise each other
2) This prevents interbreeding
3) and makes reproduction more successful.
Why is it that courtship behaviour can be used to classify animals?
Courtship behaviour can be used to classify animals because it is spceific to each species - the more closely related species are, the more similar their chourtship behaviour.
What is meant by the term ‘species diversity’?
Species diversity refers to the number and the abundance of species in a community/area.
What is meant by the term ‘biodiversity’?
Biodiversity refers to the variety of living organisms in an area.
Biodiversity can be measured using what?
Biodiversity can be measured using an Index of Diversity
What is ‘species richness’?
Species richness is a measure of the number of different species in a community
The simplest way of measuring diversity is to…
… just count the number of different species.
What is a habitat?
A habitat is a place where an organism lives
The simplest way of measuring diversity is to…
… just count the number of different species. Take random samples of an area/community and count the number of different species in the samples
What is an Index of Diversity?
An Index of Diversity is a way to measure diversity by using an equation that takes the number of different species in a community and the abundance of each species (how many individuals of each species) into account
What is the formula for calculating the index of diversity?
d = N(N-1) / Σn(n-1)
where…
N = the total number of organisms of all species
n = the total number of organisms of one species
Σ = sum of
The higher the index number…
… the more diverse an area is.
What is indicated when the index number is 1?
When the index number is 1, it indicates that there is no biodiversity/all the indiviuals are of the same species
What is ‘variation’?
Variation is the differences that exist between individuals. Variation can occur between species and within species.
What is variation that occurs between species called?
Variation that occurs between species is called inter-species variation
What is variation that occurs within species called?
Variation that occurs within species is called intra-species variation
Variation between and within species can be caused by…
- genetic factors such as different genes or different forms of genes/alleles
- environmental factors such as lifestyle, diet, climate etc.
- While most variation within a species is caused by a combination of genetic and environmental factors
