Units 6 Flashcards
DNA
double helix structure composed of two strands held together by hydrogen bonds between nitrogenous bases. stores genetic information
RNA
single stranded structure that uses uracil instead of thymine, exists for a short amount of time and is used for transcription
purines
adenine and guanine, double ring structure
pyrimidines
thymine, uracil, cytosine, single ring structure
nucleosomes
dna wrapped around histomes that pack into chromatin fibers
exons
coding regions with genetic data
introns
noncoding regions that separate exons
linear chromosomes
chromosomes that use histomes to pack themselves
circular chromosomes
smaller prokaryotes
plasmids
small, circular units of dna, chunk of dna that can hold as little as one gene, double stranded
bacterial conjugation
bacteria exchange (donate plasmids), plasmid is replicated and sent through channel
prokaryotic dna
1 circular chromosome (like string), plasmid, smaller genome, no organelle dna
eukaryotes
many linear chromosomes, limited plasmid, larger genome, organelle dna
conservative theory of replication
would happen if both strands of dna molecule stayed bonded and intact while serving as a template for an identical molecule
semiconservative theory of replication ***
two original strands separate and each serves as a template for a new strand