Studied by 1 personTrace fossils
footprints, fingerprints, burrows
Where do fossils typically form
limestone and shale in stratas
Heritable characteristics
characteristics that an organism possess due to its genetic makeup which are passed onto offspring
Macroevolution
Occurs on a large scale leading to the development of a new species
Natural selection
Occurs when a species has variation and certain traits are selected because they help the species to reach a reproductive age and pass on their genes
Selective/Artifical breeding
organism with certain characteristics are chosen by humans for some benefit
How do domesticated animals illustrate that artificial selection can cause evolution (4 points.)
The original bloodline comes from wolf-like animals. Docile wolves were accepted by humans and fed on their scraps. Allowed them to survive and reproduce, possessing on the gene. They were then bred for traits benefiting humans.
Breed
group of animals within a species with specific and similar characteristics
Microevolution
occurs on a small scale within a species
Transitional fossils
show links between species
Homologues structures
similar structures but not function
Analogus structures
Different structures but similar function
Pentadactyl limb
limb with 5 digits
Divergent evolution
when two seperate species have similar structure but use it in different ways because of their environment
Adaptive radiation
Organisms rapidly diverge from the original species into a new form to make use of different environments
Covergent evolution
When organisms that are not closely related evolve similar structures used for similar purposes
Discontinuous variation
influenced by few genes, not the environment
Continuous variation
influenced by many genes and the environment
Speciation
Process by which new species form
Speciation steps (3 steps ITR)
Isolation of populations. Trait deviation. Reproductive isolation meaning any offspring produced are infertile.
What darkened the trees in the industrial revolution
sulfur dioxide and soot
Is the dark or light allele dominant
dark
what is the moths colour pigment
melanin
is lichen light or dark
light
Industrial melanism
change in melanin production due to environmental pressures
Transient polymorphism
unbalanced allele frequency occurring gradually
Balanced polymorphism
balanced between both forms of the alleles within a population
Cause of variation (3)
Mutation, sexual reproduction and meiosis
How does mutation affect variation
changes to DNA base sequences occur in some organisms not others
How does meiosis affect variation
produces gametes with unique allele combinations
How does sexual reproduction affect variation
combination of gametes and results in zygote with a different mix of genes
Evolution/Natural selection steps (VISTA)
Variation, Inheritance, Selection/Survival, Time, Adaption
When organisms are better adapted they (reproduction)
survive and produce more offspring
Genetic drift
change in frequency of genes in a population due to random chance
Why did the finches evolve
to adapt to different food sources
When was first report on antibiotic resistance
1972
Reasons why antibiotic resistance is so common (WOCS)
Widespread usage, Occurrence in hospitals is larger due to more selective pressure, Code on plasmids which are easily exchanged, Short generation time
Clade
group of organisms evolving from a common ancestor
Node
point where divergence occurs showing speciation
Homoplasy
convergent evolution from different lineages
What are clades usually based on
DNA base sequences or amino acid sequences
Cladogram
shows evolutionary relationship of a group of organisms
Molecular clock
technique which uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged
What type of correlation between number of differences and time they diverged form a common ancestor
positive
What part of DNA is compared to see speciation
base sequence
Why do the non-coding parts of DNA provide the most information
They are highly repetitive sequences and mutations occur more frequently
Assumptions of a cladogram (FLIMB)
Frequency of nodes is relative to closeness of relationshipBranching pattern represents evolutionary relationships
Length of branches represent time since divergence
Information for extinct species
Mutations occur at constant rate
Branching pattern represents evolutionary relationships
Outgroup
most distantly related organism
Phylogenetic tree
represents evolutionary relationships among organisms based on physical and genetic similarities and differences
Artiodactyl
hoofed animals
The best classification system is one which best represents….
evolutionary history
Species
group of organisms that are able to interbreed to produce fertile offspring
Genus
group of species sharing common characteristics but not able to interbreed
Rules for naming something with a scientific name
Genus - capital and before species - lowercase, in italics
Dichotomous key
series of paired opposing statements to guide the user to the identity of an item/organism
order of organism classification (DKPCOFGS)
domain, kingdom , phylum , class , order , family , genus species .
Bacteria
No histones, glycerol D-form and peptidoglycan cell wall
Archaea
some species have histones, L-form of glycerol
Eukaryota
histones and D-form of glycerol
3 domains
bacteria, archaea, eukaryota
Heterotroph
gains energy by eating other organisms
Autotroph
produces energy through organic substances
Human classification
Eukaryota; Animalia; Chordata; Mammalia; Primata; Hominidae; Homo; sapiens
Rhizoids
small-root like structures helping bryophytes to attach to the soil
4 plant phyla
Angiospermophytes, Coniferophytes, Filicinophytes, Bryophytes
Chordata
phylum with a notochord
Note
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