Lab 1 Flashcards
(23 cards)
Why do we use sterile technique?
- Avoid contaminating cultures
2. Avoid contaminating environment and ourselves
Speciation?
Refer to event that produces 2 or more separate species from one lineage.
Unguligrade?
Hooves
Digitigrade?
Walking with toes, heels not on ground
Plantigrade?
Walking on soles of feet.
More parsimonious?
Fewer character changes
Advantages of molecular data?
Looks at similarities in AA
Specific
Disadvantages of Molecular data?
Difficult to correct
Inconsistent
Advantage to Morphological data?
Fairly accurate trees
Looks at characteristics
Disadvantages of Morphological trees?
Not accurate
Not used often
Allopatric?
geographic barrier between populations.
Sympatric?
any reproductive barrier that is not geographical appears.
Four mechanisms of eovlution?
- mutation
- genetic flow
- genetic drift
- selection
Mutations
Occurs at nucleic acid level
Formed by mistakes during DNA replication
Substitution?
Swapping out a single base
Insertion?
Inserting one or more bases
Natural selection?
Any trait that either increases or decreases an organism’s ability to survive or reproduce is subject to selective pressure
Sexual selection
describes the increase in frequency within a population of traits that improve an organism’s reproductive success
Gene flow (migration)?
The movement of individuals between populations
Genetic Drift?
Random change in allele frequency
Phylogenetics?
Show histories through branching events
Character matrix?
011010101
Molecular clock hypothesis?
When a population splits in two, the two populations accumulate different mutations over time. This continuous accumulation of fixed mutations can be used to estimate how long ago the ancestors of currently living species split into different lineages (divergence times).
