cellular control Flashcards
(35 cards)
what are mutations
random changes in DNA sequences caused by mutagens
what are the two types of mutations
point mutation
frameshift mutation
what is an example of a point mutation
substitution
what are the two examples of a frameshift mutation
insertion
deletion
what is the result of frameshift mutations
disrupts triplet codes (codon) reading
what are the three types of effects on a mutation
neutral, beneficial, damaging
what is the result of neutral mutations
has no effect due to the degenerate code
what is the result of beneficial mutations
enhanced functions of protein
what is the result of damaging mutations
malfunctioning protein made
what are the two types of damaging mutations
nonsense and missense mutations
what is the result of nonsense mutations
codon is formed into a stop codon
what is the result of missense mutations
amino acid A is formed into amino acid B
what is the feature of stop codons
premature and shorter ends
what are the types of chromosomal mutations
deletions, duplications, inversions, translocation
what is a transcriptional gene expression
altering the conditions to allow RNA polymerase to bind
what is used in transcriptional gene expressions for prokaryotes
lac operon
what is used in transcriptional gene expressions for eukaryotes
histone modification for chromatin remodelling
what is a feature of heterochromatin
tightly wound DNA in cell division
what is the result of transcribing genes in heterochromatin
it is inaccessible to RNA polymerase
what is the result of heterochromatin
prevents damage when moving
what is the feature of euchromatin
loosely wound DNA in interphase
what is the result of transcription in euchromatin
prepares cells to divide
why is DNA negatively charged
the phosphate group is negatively charged
what is an operon
a group of genes controlled by the same regulatory mechanism and expressed at the same time
