gene mutation Flashcards
somatic cells
body cells
gametes
sex cells
mutation
permenant change in DNA of organism
point / gene mutations
when just one or a small number of nucleotides are miscopied during transcription
examples of point mutations
deletion
insertion
substitions
substution mutations
where one base substitutes another base
deletion mutations
where a base is completely lost in the sequence
insertion mutations
where an extra base is added which may be a repetition of another existing base or another different one
chromosomal mutations
involves change in the position of genes within the chromosomes. this is like rewording a scentence
whole chromosome mutations
where an entire chromosome is either lost during meiosis or duplicated in one cell by errors in the process
sickle cell disease
genetic disease that affects the protein chains making up the haemoglobin in the red blood cells
result of point mutation
what happens to the haemoglobin proteins
they stick together to form rigid rods that give red blood cells a sickle shape
dont carry oxygen and block small blood vessels
what is placed instead of glutamine in SCA
valine is coded for instead of glutamine affecting haemoglobin structure
what are mutagens
anything that can increase the rate of mutation
examples of mutagens
xrays
carcinogens
ionising radiation
chemicals
