10.2. THE 5 KINGDOMS

Question 1

what are the five kingdoms?

Answer 1

• Prokaryotae (bacteria)
• Protoctista (unicellular eukaryotes)
• Fungi (e.g. yeasts, mould, mushrooms, etc)
• Plantae (plants)
• Animalia (animals)

Question 2

what are the general features of prokaryotae?

Answer 2

• unicellular
• no nucleus or other membrane bound organisms
• no visible feeding mechanism (nutrients absorbed through cell wall or produced internally by photosynthesis)

Question 3

what are the general features of protoctista?

Answer 3

• (mainly) unicellular
• 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 (autotrophic feeders), ingestion of other organisms (heterotrophic feeders), or both - some are parasitic

Question 4

what are the general features of fungi?

Answer 4

• unicellular/ multicellular
• nucleus and other membrane bound organelles and a cell wall mainly made of chitin
• no chloroplasts or chlorophyll
• no mechanisms for locomotion
• most have a body or mycelium made of threads or hyphae
• nutrients acquired by absorption, mainly from decaying material (saprophytic feeders) - some are parasitic
• most store food as glycogen

Question 5

what are the general features of plantae?

Answer 5

• multicellular
• nucleus and other membrane bound organelles incl. chloroplasts and cell wall mainly made of cellulose
• most do not move
• nutrients acquired by photosynthesis (autotrophic feeders), make their own food
• store food as starch

Question 6

what are the general features of Animalia?

Answer 6

• multicellular
• nucleus and other membrane bound organelles (no cell walls)
• no chloroplasts
• move with aid of cilia, flagella, contractile proteins sometimes in the form of muscular organs
• nutrients are acquired by ingestion (heterotrophic feeders)
• food stored as glycogen

Question 7

what are the recent changes to classification systems?

Answer 7

• originally based on observable features
• now able to study evolutionary relationships between organisms (phylogeny)
• i.e. haemoglobin determines DNA of humans and chimps (differing by one amino acid)

Question 8

how are eukarya classified (domain)?

Answer 8

• have 80s ribosomes
• RNA polymerase (responsible for most mRNA transcription) contains 12 proteins

Question 9

how are archaea classified (domain)?

Answer 9

• have 70s ribosomes
• RNA polymerase of different organisms contains between 8 and 10 proteins and is very similar to eukaryotic ribosome

Question 10

how are bacteria classified (domain)?

Answer 10

• have 70s ribosomes
• RNA polymerase contains 5 proteins

Question 11

in Woese’s system, Prokaryotae kingdom divided into two kingdoms, what are they?

Answer 11

• Archaebacteria
• Eubacteria
  the six kingdoms are therefore: Archaebacteria, Eubacteria, Protoctista, Animalia, Plantae, Fungi

Question 12

why is Eubacteria classified into its own kingdom despite being single-celled eukaryotes like Archaebacteria?

Answer 12

• their chemical makeup is different from Archaebacteria
• e.g. they contain peptidoglycan in their cell wall whereas Archaebacteria does not

Question 13

what are archaebacteria?

Answer 13

• AKA ancient bacteria
• can live in extreme environments, incl. hot thermal vents, anaerobic conditions, highly acidic environments
• e.g. methanogens live in anaerobic environments such as sewage treatment plants and make methane

Question 14

what are eubacteria?

Answer 14

• AKA true bacteria
• found in all environments, most common