Biodiversity
- A measure of the different plant, animal, fungus, and other microorganism species
worldwide, the genes they contain and the ecosystems they form
Taxonomic hierarchy
- today’s system originated from one made by Carolus Linnaeus1 (18th cent.)
- group organisms with similar characteristics into categories arranged at diff levels
- share same lower hierarchy level, closer phylogenetic relationship, more
recent common ancestor2
- same group: same fundamental similarities; same subgroup: more similarities
- domain >> kingdom > phylum > class > order > family > genus > species
- species = organisms can interbreed to produce fertile offspring3
- similar structural features + genetic materials
Nomenclature / binomial naming system
- universal scientific name w/ 2 Latin words
- printed: italics; written: underlined separately4
genus name species name
- begin with a CAPITAL LETTER - begin with a small letter
- may be abbreviated in later usage - may suggest who/where it was
T. officinale (Taraxacum officinale) discovered
Phylogenetic species concept
- Study of evolutionary relationships between organisms
- less diff rRNA sequence, more similar genetic materials, closer phylogenetic
relationship
1
father of taxonomy
2
share same higher hierarchy level, less close phylogenetic relationship, common ancestor in more
3
❌
distant past
mule (horse + donkey) (infertile)
horse 64 chromosomes + donkey 62 chromosomes > mule 63 chromosomes cannot pair up properly
during meiotic cell division to produce normal gametes > infertile
4
❌
mule: Equus asinus x Equus caballas
tilt handwriting
, - closer branches in evolutionary tree
Convergent evolution Divergent evolution
Organisms have analogous features due to Species become more specialised to their
evolving in a similar habitat (same niche) diff niches
>> X rely on morphological features for Organisms have homologous features due
classification to common ancestor
Molecular evidence to aid classification
Cytochrome C DNA
Protein involved in respiration, found in all Codes for primary AA sequence
living organisms (all respire) >> DNA sequence compared: more similar,
>> AA sequence compared: more similar, more closely related
more closely related
3 domains
Difference between bacteria and archaea Similarities between archaea and
eukaryotes
- Cell membrane structure - Similar RNA polymerase for
- Internal structure of flagella synthesising RNA
- Type of RNA polymerase - Similar mechanisms for DNA
- Have no proteins bound to their replication and synthesis
DNA - Production of some proteins which
- Diff mechanisms for DNA bind to their DNA
replication and synthesis
Classification is dynamic and is constantly revised w new evidence
1. Bacteria
-most are harmless
-important for human
survival
2. Archaea
-more ancient
-@extreme environment
-less understanding
-more closely related to
Eukarya than Bacteria
3. Eukarya
, -Plants more closely
related to protista
than fungi
-Fungi more closely
related to animals than
plants
Levels of organisation (lowest > highest)
species group of organisms with similar morphology, physiology and behaviour
which interbreed to produce fertile offspring
which are reproductively isolated from other species
How body features adapt to habitat?
population group of organisms of same species living in same habitat
How abiotic factors affect population size?
temp, light, rain/humidity, wind, oxygen level, salinity, substratum
nature
community all populations of diff species (biotic) living in same habitat
w/ certain deg of interdependence:
- mutual tolerance commensalism
- beneficial interaction mutualism, competition
- feeding relationships predation, parasitism
- withstand any harmful effects
How diff species(biotic) interact?
ecosystem natural unit of living components + non-living components
- interact to form a self-supporting, stable yet dynamic
system
eg. woodland, rocky shore, mangrove, stream
How materials cycled (btwn biotic + abiotic)?
carbon cycle, nitrogen cycle
biome similar ecosystems spanning large geographical area (on earth) with
similar climatic conditions
- characterised by dominant plant type
eg. savanna (africa, india, N australia, middle S america), grassland,
tropical RF, tundra, temperate deciduous forest
How changes in earth climate affect orgs in biome?
biosphere entire space on earth’s surface where organisms exist
- A measure of the different plant, animal, fungus, and other microorganism species
worldwide, the genes they contain and the ecosystems they form
Taxonomic hierarchy
- today’s system originated from one made by Carolus Linnaeus1 (18th cent.)
- group organisms with similar characteristics into categories arranged at diff levels
- share same lower hierarchy level, closer phylogenetic relationship, more
recent common ancestor2
- same group: same fundamental similarities; same subgroup: more similarities
- domain >> kingdom > phylum > class > order > family > genus > species
- species = organisms can interbreed to produce fertile offspring3
- similar structural features + genetic materials
Nomenclature / binomial naming system
- universal scientific name w/ 2 Latin words
- printed: italics; written: underlined separately4
genus name species name
- begin with a CAPITAL LETTER - begin with a small letter
- may be abbreviated in later usage - may suggest who/where it was
T. officinale (Taraxacum officinale) discovered
Phylogenetic species concept
- Study of evolutionary relationships between organisms
- less diff rRNA sequence, more similar genetic materials, closer phylogenetic
relationship
1
father of taxonomy
2
share same higher hierarchy level, less close phylogenetic relationship, common ancestor in more
3
❌
distant past
mule (horse + donkey) (infertile)
horse 64 chromosomes + donkey 62 chromosomes > mule 63 chromosomes cannot pair up properly
during meiotic cell division to produce normal gametes > infertile
4
❌
mule: Equus asinus x Equus caballas
tilt handwriting
, - closer branches in evolutionary tree
Convergent evolution Divergent evolution
Organisms have analogous features due to Species become more specialised to their
evolving in a similar habitat (same niche) diff niches
>> X rely on morphological features for Organisms have homologous features due
classification to common ancestor
Molecular evidence to aid classification
Cytochrome C DNA
Protein involved in respiration, found in all Codes for primary AA sequence
living organisms (all respire) >> DNA sequence compared: more similar,
>> AA sequence compared: more similar, more closely related
more closely related
3 domains
Difference between bacteria and archaea Similarities between archaea and
eukaryotes
- Cell membrane structure - Similar RNA polymerase for
- Internal structure of flagella synthesising RNA
- Type of RNA polymerase - Similar mechanisms for DNA
- Have no proteins bound to their replication and synthesis
DNA - Production of some proteins which
- Diff mechanisms for DNA bind to their DNA
replication and synthesis
Classification is dynamic and is constantly revised w new evidence
1. Bacteria
-most are harmless
-important for human
survival
2. Archaea
-more ancient
-@extreme environment
-less understanding
-more closely related to
Eukarya than Bacteria
3. Eukarya
, -Plants more closely
related to protista
than fungi
-Fungi more closely
related to animals than
plants
Levels of organisation (lowest > highest)
species group of organisms with similar morphology, physiology and behaviour
which interbreed to produce fertile offspring
which are reproductively isolated from other species
How body features adapt to habitat?
population group of organisms of same species living in same habitat
How abiotic factors affect population size?
temp, light, rain/humidity, wind, oxygen level, salinity, substratum
nature
community all populations of diff species (biotic) living in same habitat
w/ certain deg of interdependence:
- mutual tolerance commensalism
- beneficial interaction mutualism, competition
- feeding relationships predation, parasitism
- withstand any harmful effects
How diff species(biotic) interact?
ecosystem natural unit of living components + non-living components
- interact to form a self-supporting, stable yet dynamic
system
eg. woodland, rocky shore, mangrove, stream
How materials cycled (btwn biotic + abiotic)?
carbon cycle, nitrogen cycle
biome similar ecosystems spanning large geographical area (on earth) with
similar climatic conditions
- characterised by dominant plant type
eg. savanna (africa, india, N australia, middle S america), grassland,
tropical RF, tundra, temperate deciduous forest
How changes in earth climate affect orgs in biome?
biosphere entire space on earth’s surface where organisms exist
