inquiry question 1 Flashcards
(15 cards)
what can cause a mutation
mutagens or cellular errors
mutation definition
changes to an organisms DNA sequence
mutagen definition
a chemical, physical, or naturally occurring agent that is capable of creating change to a sequence of DNA
types of mutations
point mutations and chromosomal mutations
what is a point mutation
alterations to 1-3 bases
bases can be replaced (substituted)
bases can also be inserted or deleted from a sequence
what are the results of a point mutations
missense mutation
silent mutation
nonsense mutation
frame shift
missense mutation
a wrong base is inserted
the wrong amino acid is added into a protein
silent mutation
there is no change to the amino acid sequence
only occurs when more than 1 codon codes for a particular amino acid
nonsense mutation
the insertion of a stop codon
the transcript stage prematurely stops and the complete protein cannot form
what is a frameshift mutation and the result of it
the reading frame of the bases are changed once bases have been inserted or deleted
the amino acid sequence is altered, and could lead to a non-functioning protein
what are chemical mutagens
free radicals : molecules with unpaired electrons, making them highly reactive
what are the ways chemical mutagens act (types)
intercalating agents
base analogues
DNA reactive chemicals
what are physical mutagens
an agent that alters the DNA of an organism, and generally involves radiation
can be ionising, or non-ionising
examples of physical mutagens
