Biodiversity and classification Flashcards
Classification
The process of naming and organising organisms into a group based on their characteristics and evolutionary history.
Can the classification of an organism change?
The classification of an organism may change as new info becomes available.
Name the hierarchy of taxons in order from largest to smallest.
Kingdom, phylum, class, order, family, genus, species.
Name the 5 kingdoms.
Animalia, fungi, plantae, prokaryotes and protocista.
What is the three domain classification system?
A method of classification in which organisms are categorised into three groups; Archaea, Bacteria and Eukarya.
How was the three domain classification system developed?
Was developed by analysing molecular differences between organisms to determine their evolutionary relationships. Evidence showed that the kingdom ‘prokaryotae’ could be divided into two groups and all other organisms are eukaryotes.
What do organisms in the same domain have in common?
Organisms in the same domain share a distinctive pattern of ribosomal RNA.
Bacteria
One of the three domains and consists of ‘true’ bacteria.
Archaea
One of the three domains, made up of primitive bacteria existing in extreme environments.
Eukarya
One of the three domains and consists of all eukaryotic organisms.
Features of the kingdom Prokaryotae
- Unicellular prokaryotes
- Lack of a true nucleus and membrane-bound organelles.
- Rigid cell wall.
Features of the kingdom Plantae
- Multicellular eukaryotes
- Photoautotrophs
- Cellulose cell walls
Features of the kingdom Animalia
- Multicellular eukaryotes
- No cell wall
- Heterotrophic
- Nervous coordination
Features of the kingdom Fungi
- Eukaryotes
- Heterotrophic
- Chitin cell walls
- Grow by producing branching filaments called hyphae
- Asexual reproduction via spores
Features of the kingdom protoctista
- Mainly unicellular eukaryotes
- No differentiation into tissues
Different types of evidence used in classification:
- Observations (organisms grouped based on similar physical characteristics).
- Biochemical methods.
DNA profiling
A method of determining the characteristics of an individual’s DNA - percentage of DNA or proteins shared between species is used to estimate relatedness.
The advantage of using biochemical methods of classification.
Reduce mistakes made from observing physical features alone (due to morphological convergence).
Homologous features
Have evolved from the same structure for different functions. They indicate a common ancestor.
Analogous features
Structures that have evolved independently for the same functions.
Species
A group of organisms that can interbreed to produce fertile offspring.
What are the two components to a binomial name?
The genus and the species.
What is the advantage of binomial naming?
The binomial system is universal.
Biodiversity
The number of species and the number of individuals if each species in a specified geographic region.
