Module 7 - Phylogeny Flashcards
biologists define a species as
a group of popula tions that evolves independently. of each other. an organism of the same species has potential to reproduce.
reproductive isolation
(inability to successfully breed outside the group)
why it is difficult to develop a criterion for distinguishing species?
some species cannot breed with each other but may seem identical to humans in every single aspect. a species may be able to breed while appearing extremely different in characteristics. for example dogs
speciation
the process of species formation, in which a single species splits into two or more species
Premating isolation:
any structure, physiological function, or behaviour that prevents organisms of two different species from mating
Postmating isolation:
any structure, physiological function, or developmental abnormalities that prevents organisms of two different species from producing vigorous, fertile offspring after mating has occurred
Polyploidy:
having more than two copies of each homologous chromosome
Adaptive radiation:
the rise of many new species in a relatively short time; this may occur when a single species invades different habitats and evolves in response to different environmental conditions within those habitats
Phylogeny:
the evolutionary history of a group of species
Monophyletic:
a monophyletic group or clade, is a group of organisms that consists of all the descendants from a common ancestor
Clade:
a group that includes all the organisms descended from a common ancestor
Taxonomy:
the branch of biology concerned with naming and classifying organisms
Binomial nomenclature:
the method of naming organisms by genus and species (two part), often called the scientific name
Biodiversity
all living things; biological diversity
The eight major taxonomic ranks of the Linnaean system
Domain, Kingdom, Phylum, Class, Order, Family, Genus , Species
Archaea lack ? and often have the ability to produce ?
a microorganism that lack cell nuclei and are therefore prokaryotes, extreme environments, often have ability to produce methane.
Eukarya
An organism whose cells contain a nucleus surrounded by a membrane. All organisms except for bacteria, cyanobacteria, and the bacteria-like organisms known as archaea are eukaryotes.
differences that distinguish members of the Bacteria from the Archaea
Similar to bacteria, archaea do not have interior membranes but both have a cell wall and use flagella to swim. Archaea differ in the fact that their cell wall does not contain peptidoglycan and cell membrane uses ether linked lipids as opposed to ester linked lipids in bacteria.
the specializations that have allowed prokaryotes to thrive in a diversity of habitats
Endospores enable bacteria to lie dormant for extended periods, even centuries or thousands of years. When the environment becomes more favourable, the endospore can reactivate itself to the vegetative state.
endospores
An endospore is a dormant, tough, and non-reproductive structure produced by certain bacteria. It is a stripped-down, dormant form to which the bacterium can reduce itself. Endospore formation is usually triggered by a lack of nutrients and usually occurs in gram postive bacteria.
nitrogen fixation
Nitrogen‐fixing bacteria live in the soil and convert nitrogen gas to ammonium, which can be absorbed by plants.
Prokaryotes play important roles in animal nutrition;
cellulose digesters live in the digestive tract of many leaf‐eating organisms.
In humans, some bacteria use food products to produce
Vitamins K and B12
bioremediation
is the process of using prokaryotes to clean up pollutants
Viroids:
a particle of RNA that is capable of infecting a cell and of directing the production of more viriods. These are prevalent as a plant disease agent
