topic 10 classification and evolution Flashcards
(63 cards)
species
a group of organisms that can reproduce to produce live, fertile offspring
what does classification allow scientists to do
-identify new species
-study evolutionary relationships
-understand shared traits and adaptations
-share research globally to identify links with organisms on other continents
problems with common names
- species can have a different common name in different places
-different species can have the same common name
when was the linnaean classification system discovered
1700s
lots of taxon are called
taxa
is the taxonomic group hierarchical
yes
broadest groups containing the most species at top and most specific groups at bottom
the 8 major taxonomic groups
domain
kingdom
phylum
class
order
family
genus
species
three domains orgnisms can be classified into
bacteria
archaea
eukarya
which domain includes all eukaryotes
eukarya
4 kingdoms in eukarya
plantae (plants)
animalia (animals)
protoctista (unicellular eukaryotes)
fungi (eg yeasts)
he binomial name consists
-the genus- has uppercase first letter
-the species - all lowercase
underlined or italicised when written down
the five kingdom system was developed as more organisms were discovered. what are they
prokaryotae
animalia
plantae
fungi
protoctista
which of the five kingdoms are eukaryotic
animalia
plantae
fungi
protoctista
prokaryotae features
-all unicellular
-no nucelus or membrane bound organelles
-dna forms circular loop and not bound to histone proteins
-small 70S proteins
-nutrients by absorbtion from the environment through the cell wall or by photosynthesis
-autotrophic, heterotrophic or parasitic
-contain cell wall often made of peptidoglycan
-stores sugar in glycogen
-reproduces through binary fission
animalia features
-all multicellular organisms
-heterotrophic
-glucose is stored as polysaccharide glycogen
-cells of animalia have a nucleus and membrane bound organelles but never chloroplasts or a cell wall
-movement often occurs by protein contraction (Eg muscles)
-reproduction can vary
plantae features
-multicellular
-cellulose cell wall as well as chlorophyll in chloroplasts
-autotrophic and use photosynthesis
-glucose stored as starch
-most dont move but have exceptions like the venus fly trap and in some the male gametes use flagella t o move
-contain nucleus and membrane bound organelles
-use seeds or spores to reproduce
fungi features
-unicellular or multiccellular w a body made of hyphae
-cell wall made of chitin
-consist of fine threads called hyphae forming a larger mass called mycelium
-cannot move and cannot photosynthesise and never contain chlorophyll
-fungi are saprophytes meaning they absorb nutrients from around them often from decaying matter
-use glycogen as a storage form of glucose
-some fungi are parasites
-reproduce through spores
protocista features
-most are unicellular but some are multicellular
-can be heterotrophic such as amoeba or autotrophic like euglena. some are parasites like giardia
-some move using flagella or cillia while amoeba move by spreading which is called amoeboid movement. some have no active mechanism of moving at all
-nucleus and other membrane bound organelles are present sometimes including chloroplasts
why did Carl Woese propose a new taxonomic group
he analysed ribosomal RNA from a range of prokaryotes including Ecoli and found archeabacteria are very different to bacteria such as Ecoli such as the cell wall does not contain peptidoglycan and
different protein synthesis
what was the new taxonomic group carl woese proposed
domain
what did the three domain system propose and why
six kingdoms instead of five because there is evidence for splitting the kingdom prokayote into two seperate kingdoms, eubacteria and archeabacteria
domain bacteria features
-contains the kingdom eubacteria only, found in all environments
-prokaryotic unicellular organisms
-distinct cell membrane lipids
-have peptidoglycan in their cell walls
-unique RNA polymerase enzyme
domain archae features
-contains the kingdom archeabacteria only, typivally found in extreme environments
-prokaryotic unicellular organisms
-have histones so genes and protein synthesis is more similar to eukarya than bacteria
-no peptidoglycan in their cell walls
-different cell membranes that contain fatty acids bound to glycerol by either linkages
-have more complex form of RNA polymerase than bacteria
domain eukarya
-contains four kingdoms from the five kingdom system, animalia, plantae, fungi, protoctista
-all have nucli and membrane bound organelles