4.2.2 Flashcards
(47 cards)
What are taxonomic groups?
Kingdom Phylum Class Order Family Genus Species
What is another word for hierarchical classification systems?
Linnaean classification
Why is classification used?
- Identify species
- predict characteristics
- find evolutionary links
How organisms are classified?
They are first split into three domains:
- archaea
- bacteria
- eukarya
What is the binomial nomenclature?
First word: organism genus
Second word: organism species
What are the five kingdoms?
Procaryotae Protoctista Fungi Plantae Animalia
Describe prokaryotae
Unicellular
No membrane-bound organelles
No visible feeding mechanism
Describe protoctista
Unicellular
Has a nucleus and other membrane-bound organelles
Some of sessile, some move
Nutrients are required in one of two ways:
-Photosynthesis (autotrophic feeders)
-Ingestion of other organisms (heterotrophic feeders)
Or both
Some are parasitic
Describe fungi
Unicellular/multi cellular
Chicken cell wall
New mechanisms for locomotion
Body made of mycelium made of threads/hyphae
Nutrients acquired by absorption (saprophytic feeders)
Describe plantae
Multi cellular
Sam can move using cilia/flagella
Nutrients acquired by photosynthesis (autotrophic feeders)
Describe Animalia
Multicellular
Move with cilia/flagella/contractile proteins/muscular organs
Nutrients acquired by indigestion (heterotrophic feeders)
What’s the difference between the ribosomes in E, A, B? And how many proteins do each of these RNA polymerise have?
Eukarya: 80s, 12 proteins
Archaea: 70s, 8-10 proteins
Bacteria: 70s, 5 proteins
What is phylogeny?
Evolutionary relationships between organisms
What is phylogenetics?
Study of evolutionary history,
Reveals which group a particular organism is related to and how closely
What do you phylogenetic trees show?
evolutionary tree is used to represent evolutionary relationships between organisms
What are the three advantages of phylogenetic trees?
- doesn’t need reference to linnaean classification
- Continuous tree, unlike discrete taxonomical groups (scientists not forced to put organisms in groups they don’t fit)
- Hierarchical nature of Linnean classification can be misleading as it implies different groups in same rank are equivalent
What is palaeontology?
Study of fossils and fossil record
What is comparative anatomy?
Similarities and differences between organisms anatomy
What is comparative biochemistry?
Similarities and differences between chemical make-up of organisms
Why is it possible to know the fossil record?
Fossils preserved in rocks
Sediment is deposited (forming layers – strata – of rocks)
Different layers correspond to different geological eras
What does the evidence from palaeontology tell you?
- Simple life involves (bacteria and simple algae in oldest rocks but more complex vertebrates in recent rocks)
- Sequence in which they are found match ecological links to each other
- can investigate extinct and living organisms
Why are some fossil record is not complete?
- Some of softbodied (decompose before they can fossilise)
- some destroyed in earth movements
- some are undiscovered
What is a homologous structures?
They appear to be superficially different but they have the same underlying structure
Provides evidence of divergent evolution (happens when closely related species diversify to adapt)
How is comparative biochemistry done?
Proteins and other molecules that control life processes are studied
E.g. cytochrome and ribosomal RNA