Lesson 2 - The five kingdoms Flashcards
What were the original 2 kingdoms?
Plants and animals
What did the animal kingdom include? Aristole
Every living creature that moved, ate and grew
What discoveries critiqued the 2 kindgoms system?
- The invention of the microscope. Bacteria could be seen
What were the 5 kingdoms
Prokaryota (bacteria)
Protocista (the unicellular eukaryotes)
Fungi (yeast, moulds, mushrooms)
Plantae (plants)
Animalia (animals)
What of the original 5 kingdoms were prokaryotes
Prokaryotae
Prokaryote features
- Unicellular
- No nucleus or other membrane-bound organelles (a ring of ‘naked’ DNA and small ribosomes)
- No visible feeding mechanism (nutrients are absorbed through the cell wall or produced internally by photosynthesis
Examples of prokaryotae?
- Esherichia coli
- Staphylococcus aureus
- Bacillus anthracis
Protoctista features
- (mainly) unicellular
- A nucleus and other membrane-bound organelles
- have some chloroplasts
- Some are sessile, others move by cilia, flagella or amoeboid mechanisms
- Nutrients are acquired by photosynthesis (autotrophic feeders), ingestion of other animals (heterotrophic feeders), or both
Protocista examples
- Paramecium
- Amoeba
Heterotrophic feeders
Ingestion of other animals for nutrients
Autotrophic feeders
Nutrients acquired by photosynthesis
Fungi features
- 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
Plantae features
- Multicellular
- Nucleus and other membrane-bound organelles including chloroplasts and a cell wall mainly composed of 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 of plantae?
Flowering plants, such as roses, trees such as oak and grasses
Animalia features
- Multicellular
- 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 (heterotrophic feeders)
- Food stored as glycogen
An example of a protein that has changed shape?
Haemoglobin.
Haemoglobin in humans differs from haemoglobin in chimpanzees in only one amino acid, gorillas in 3 amino acids, gibbons in 8 amino acids.
What is the current classification system?
‘Three Domain System’ - Proposed by Carl Woese
(Domain was originally called kingdom so that there were two)
How did Woese group organisms?
Using differences in the sequences of nucleotides in the cells’ ribosomal RNA (rRNA) as well as the cells’ membrane lipid structure and their sensitivity to antibiotics.
Woese’s classification of Eukarya?
80s ribosomes.
- RNA polymerase contains 12 proteins
Woese’s classification of Archaea?
Contains 70s ribosomes
- RNA polymerase of different organisms contains between eight and 10 proteins and is very similar to eukaryotic ribosome
Woese’s classification of Bacteria?
70s ribosomes
- RNA polymerase contains 5 proteins
How is the chemical make-up of Archaebacteria and Eubacteria different?
Eubacteria contain peptidoglycan (polymer of sugars and amino acids) in their cell wall whereas Archaebacteria do not.
Examples of conditions Archaebacteria can live in?
- Hot thermal vents
- Anaerobic conditions
- Highly acidic environments
Methanogens live in sewage treatment plants and make methane
Saprotrophic meaning:
- secrete digestive enzymes to feed
