3.1 Flashcards
(8 cards)
Hierarchy for classification
Do kids prefer chocolate over fresh green salad
Domain kingdom phylum class order family genus species
Understand the limitations of the definition of a species as a group of organisms with similar characteristics that interbreed to produce fertile offspring.
all organisms don’t live in same areas: so can’t interbreed to form fertile offspring.
Lions and tigers can’t interbreed specifically but not same species
Understand why it is often difficult to assign organisms to any one species or to identify new species.
similar appearance, no info on breeding} dif to classify species as dif bc species can interbreed, species evolving over time
Understand how gel electrophoresis can be used to distinguish between species and determine evolutionary relationships.
obtain DNA from 2 types, use restriction enzymes to cut DNA into fragments and use PCR to amplify DNA, load fragments on agarose gel w pd applied, DNA fragments are positively charged (phosphate grp), therefore fragments move when pd applied towards +ve electrode, fragments move at dif speeds, use UV light to see banding, more similar banding suggest same species - as most closely related to common ancestor, produces individual DNA profiles as difs in each individual’s DNA so produce fragments of dif lengths which are separated
What can be used to distinguish between species and determine evolutionary relationships.
DNA sequencing and bioinformatics
Understand the evidence for the three-domain model of classification as an alternative to the five-kingdom model and the role of the scientific community in validating this
using techniques of molecular phylogeny - which found sims + difs bw archeae + bacteria like membrane structure, membrane proteins, membrane bound organelles
3 domains
Domains: archaea, eukarya, eukaryota
5 kingdoms
Domains: archaea, eukarya, eukaryota
Kingdoms: animalia, protista
