10 Classification Flashcards
What is classification?
Classification is the name given to the process by which living organisms are sorted into groups.
What are taxonomic groups?
The hierarchical groups of classification- domain, kingdom, phylum, class, order, family, genus, species
What are the seven groups?
Kingdom Phylum Class Order Family Genus Species
Whar is the biggest and broadest taxonomic group?
Kingdom
What is the smallest and most specific classification?
Species
Why do scientists classify organisms?
1) To identify species- by using a clearly defined system of classification, the species an organism belongs to can be easily identified.
2) To predict characteristics- if several members in a group have a specific characteristic, it is likely that another species in the group will have the same characteristic.
3) To find evolutionary links- species in the same group probably share characteristics because they have evolved from a common ancestor.
- By using a single classification system, scientists worldwide can share their research. Links between different organisms can be seen, even if they live on different continents.
What three domains can the classification system be separated into?
Archea, Bacteria, and Eukarya
What is binomial nomenclature?
The scientific naming of a species made of two parts- the first indicating the genus and the second the species.
What are the five kingdoms?
Living organisms can be classified into five kingdoms:
- Prokaryotae (bacteria)
- Protoctista (the unicellular eukaryotes)
- Fungi (e.g yeasts, moulds and mushrooms)
- Plantae (the plants)
- Animalia
What are the general features of prokaryotae?
- Unicellular
- No nucleus or other membrane bound organelles- a ring of ‘naked’ DNA- small ribosomes
- No visible feeding mechanism- nutrients are absorbed through the cell wall or produced internally by photosynthesis.
Examples include the bacteria: Escherichia coli, staphylococcus aureus, and Bacillus anthracis
what are the general features of protoctista?
- (Mainly) unicellular
- A nucleus and other membrane bound organelles
- Some have chloroplasts
- Some are sessile, but others move by cilia, flagella, or by amoeboid mechanisms
- Nutrients are acquired by photosynthesis, ingestion of other organisms, or both- some are parasitic.
Examples include species belonging to the genera Paramecium and Amoeba.
What are the general features of Fungi?
- Unicellular or multicellular
- A nucleus and other membrane bound organelles and a cell wall mainly composed of chitin
- No chloroplasts or chlorophyll
- No mechanisms for locomotion
- Most have a body or mycelium made of threads or hyphae
- Nutrients are acquired by absorption- mainly from decaying material- they are saprophytic feeders- some are parasitic
- Most store their food as glycogen
- Examples include mushrooms, moulds and yeast.
What are the general features of animalia?
- Multicellular
- A nucleus and other membrane bound organelles (no cell walls)
- No chloroplasts
-Move with the aid of cilia, flagella, or contractile proteins sometimes in the form of muscular organs - Nutrients are acquired by ingestion, they are heterotrophic feeders
- Food stored as glycogen.
Examples include mammals such as cats, reptiles such as lizards, birds, insects, molluscs, worms, sponges, and anemones.
What are the general features of plantae?
- Multicellular
- A nucleus and other membrane bound organelles including chloroplasts, and a cell wall mainly composed to cellulose.
- All contain chlorophyll
- Most do not move, although gametes of some plants move using cilia or flagella
- Nutrients are acquired by photosynthesis - they are autotrophic feeders- organisms that make their own food.
- Store food as starch.
- Examples include flowering plants such as roses, trees such as oak and grasses.
Three Domain System: Eukarya
- Eukarya has 80s ribosomes.
- RNA polymerase contains 12 proteins.
Three domain system: Archaea
- They have 70s ribosomes
- RNA polymerase of different organisms contain between eight and ten proteins and is very similar to eukaryotic ribosome.
Three domain system: Bacteria
- They have 70s ribosomes.
- RNA polymerase contains five proteins.
How many kingdoms does Woese’s system have and why?
Six.
- This is because the prokaryotae kingdom becomes divided into two- Archebacteria and Eubacteria.
- The six kingdoms are therefore: Archaebacteria, Eubacteria, Protoctista, Fungi, Plantae and Animalia.
Why are eubacteria classified in their own kingdom?
- Eubacteria are classified in their own kingdom because their chemical makeup is different from Archaebacteria.
- For example, they contain peptidoglycan in their cell wall whereas Archaebacteria do not.
What are archaebacteria?
- Archaebacteria also known as ancient bacteria can live in extreme environments.
- These include hot thermal vents, anaerobic conditions, and highly acidic environments.
- For example, methanogens live in anaerobic environments such as sewage treatment plants and make methane.
What are eubacteria?
- Eubacteria, also known as true bacteria, are found in all environments and the ones you are most familiar with.
- Most bacteria are of the eubacteria kingdom.
What is phylogeny?
- Phylogeny is the name given to the evolutionary relationships between organisms.
What is phylogenetics?
- The study of the evolutionary history of groups of organisms.
What is phylogenetic tree?
- A phylogenetic tree is a diagram used to represent the evolutionary relationships between organisms.
- Phylogenetic trees are produced by looking at similarities and differences in species’ physical characteristics and genetic makeup.
- The closer the branches, the closer the evolutionary relationship.