1.2 organizing diversity of life Flashcards
biologists have so far identified and named how many species
1.8 million
? species of prokaryotes discovered
6,300
estimated total a=mount of species? (including undiscovered)
10 million-100million
how do scientists classify things
the Linnaeus system: Domain Kingdom Phylum Class Order Family Genus Species
the branch of biology that names and classifies species/ formalizes the ordering of species into groups of increasing breadth:
taxonomy
five original kingdoms
plants animals fungi single celled eukaryotes prokaryotes
what new methods have led to a reevaluation of the number and boundaries of kingdoms
ex. comparisons of DNA from different species
three domains
bacteria
archaea
Eukarya
which two domains are all prokaryotic
bacteria and archaea
the most diverse and widespread prokaryotes and now divided into multiple kingdoms:
domain bacteria
extreme environments
includes multiple kingdoms :
domain archaea
unicellular eukaryotes and relatively simple multicellular relatives:
kingdom Protista
absorbs nutrients from surroundings:
kingdom fungi
multicellular eukaryotes that carry out photosynthesis:
kingdom Plantae
multicellular eukaryotes that ingest other organisms:
kingdom Animalia
example of unity in diversity
the cilia on a paramecium and the cilia in a windpipe of a human
darwin’s book
on the origin of species by means of natural selection
two points of Darwin;s book
1) contemporary species evolved from ancestors (descent with modification)
2) the mechanism for descent with modification is natural selection
the mechanism for descent with modification
natural selection
Darwin’s observations
1-individuals in a population vary in traits
2-overproduction, so competition is inevitable
3- species suit their environments
Darwin’s inferences
1-individuals that are more fit reproduce more
2- over time the pop with better traits will increase
3-evolution occurs
