Virginia's Cards Flashcards
DNA Polymerase
catalyzes the synthesis of new DNA by adding nucleotides to an existing chain
Okazaki fragments
a series of segments synthesized discontinuously from the lagging strand
Leading vs. Lagging strand
synthesis of the strand occurs concurrently and at the same rate. The lagging strand is so named because its synthesis is delayed slightly relative to synthesis of the leading strand; each new fragment of the lagging strand cannot be started until enough template has been exposed at the replication fork
Topoisomerase
a protein that helps relieve the strain of the double helix by breaking, swiveling, and rejoining DNA strands
Ligand
any molecule that specifically binds to another molecule (often a larger one [ex: on cell membrane])
Catastrophism
the principle advocated by Georges Cuvier that events in the past occurred suddenly and were caused by mechanisms different from those operating in the present
Uniformitarianism
Charles Lyell’s idea that stated that mechanisms of change are constant over time
Analogous
structures that share similar functions, but not common ancestry; species share features because of convergent evolution
Homology
related species can have characteristics that have an underlying similarity yet function differently. ex: mammalian forelimbs
Vestigial structures
remnants of features that served important functions in the organism’s ancestors
Polyploidy
an accident in cell division that results in extra sets of chromosones
Allopatric speciation
(allos= other, patric= homeland) the creation of a new species when gene flow in interrupted when a population is divided into geographically isolated subpopulations
Sympatric speciation
(syn= together) speciation that occurs in populations that live in the same geographic area
Transpiration
the loss of water vapor from leaves and other aerial parts of the plant
Cognition
the process of knowing that involves awareness, reasoning, recollection, and judgement
