classification Flashcards
what is classification?
process of ordering things into groups
state the order of the taxonomic rank
domain, kingdom, phylum, class, order, phylum, genus, species
what are the 3 domains?
archaea, eubacteria and eukaryotes
what are the 5 kingdoms?
plantae, Animalia, fungi, protoctista, prokaryote
why are eukaryotes more likely to evolve compared to prokaryotes ?
have non coding gaps in DNA sequence which allow for genes to be shuffled into many orders. prokaryotes are squished up so hard to shuffle
what are the rules of naming?
genus then species, genus must have a capital, species all lower case, abbreviated and underlined
H.sapien(underlined)
what are 3 advantages to the binomial naming system ?
1) names universal so all countries use same name which avoids confusion between languages
2)it means it is easy to identify organism
3) helps us see relationships between species
what are characteristics of Animalia?
eukaryote, multicellular, able to move, heterotrophic
what are characteristics of plantae?
eukaryote, multicellular, autotrophic, contain chlorophyll, cellulose cell wall
what are characteristics of fungi?
eukaryotic, unicellular (or have hyphae), mostly free living, walls made of chitin, cytoplasm that is multinucleate, saprophytic
what are characteristics of Protoctista?
eukaryotic, unicellular (apart from algae), free living, autotrophic or heterotrophic, show plant or animal like features
what are characteristics of prokaryotes?
no nucleas, no membrane bound organelles, smaller ribosomes, free living or parasitic, have naked DNA (not associated with histone proteins)
what is heterotrophic?
digest large molecules and turn these to smaller molecules for absorption
what is autotrophic?
absorb simple molecules and build up to larger ones
what is saprophytic?
causes decay
what is the phylogenetic definition of a species?
a group of individual organisms that are very similar in appearance, anatomy, physiology, biochemistry and genetics
what is the niche of an organism ?
functional role it plays in the ecosystem
what Is convergent evolution?
when 2 unrelated species could look the same because of the way the environment shapes them
how are biological molecules evidence of evolution?
if the earliest living things had identical versions of the molecules then the differences are due to evolution. differences of the molecules between species reflect evolutionary relationships
if 2 organisms had similar biological molecules what does this suggest about their relationship ?
closely related, not evolved separately for long
how can cytochrome c be used as evidence for evolution?
the amino acids of cytochrome c can be sequences and compared between species
if cytochrome c sequence same/similar what is the relationship of the 2 species?
closely related
what Is phylogeny?
study of evolutionary relationships between organisms and how closely related a species is to another
describe artificial classification
groups things for convenience
based off a few characteristics
doesn’t reflect evolutionary relationships
provides limited info
stable
describe natural classification
Putting organisms into groups that reflect how closely related they are to each other.
used many characteristics
reflects evolutionary relationships
provides lots of infomation
may change with advancing information
what is monophyletic?
when all organisms from that group evolved from one ancestor
what is a common ancestor?
an ancestor that is shared by 2 or more different organisms that is not present today
what is natural selection?
how features of the environment apply a selective force on reproduction of a individual in a species
how was variation found by Darwin?
found that there was a difference between members of same species in different environments
what are Darwins 4 observations ?
1) offspring areas similar to parents
2) no 2 individuals are indentical
3) organisms can produce large numbers of offspring
4) populations tend to remain fairly stable in size
what is the process of natural selection ?
random mutation produces new alleles of a gene, under certain conditions new alleles will benefit the organism who possesses it, therefore leads to increased chance of survival and reproductive success so the new allele is passed down generations and becomes a common trait in the species
what did the use of fossil evidence find?
that past speices were different from those present today, new species similar to old ones in same environment
why is the fossil record not complete?
not all organisms long ago would have been eaten or decayed before turned into fossils and we can’t find all of them
how is biological molecules evidence of natural selection?
all species have similar biological molecules so suggests one species gave way to another and we all arose from a single ancestor
the greater number of similarities in gene sequences means what for the relationship ?
more closely related, and more recent separation into evolution
what is variation?
presence of differences between induviduals
what are the 2 types of variation?
continuous and discontinuous
what is continuous variation ?
have 2 extreme values and a range in-between (height)
what is discontinuous variation?
have distinct categories ( blood group )
is continuous variation regulated by one or more gene? and environment?
more than one, and environment
is discontinued variation regulated by one or more genes ? and environment ?
just one, no environment
what graph would continuous variation represent ?
histograms
what graph would discontinuous variation represent?
bar chart
what is intraspecific variation?
variation between individuals in a species
what is interspecific variation?
variation between species
what effect does both environmental and genetic variation have?
one will limit the other. or the environment will switch on genes
How is phylogeny related to classification ?
Phylogeny reflects evolutionary relationships and natural classification will place organisms into groups that are related it will show how closely related the groups are
What is the definition of adaption ?
A characteristic that enhances survival in the habitat
What are 7 adaptations of marram grass
Long roots, roots spread out, leaves curled, lower epidermis covered in hairs and folded to create pits for stomata, low density of stomata, thick waxy cuticle
What are the 3 types of adaptation ?
Anatomical, behavioural and physiological
