Lecture 32 Flashcards
mutation
permanent change in nucleotide sequence of DNA
mendel
change in genotype can lead to change in phenotype
genotype
total set of alleles for and organism; sequence of nucleotides coding for specific amino acids
phenotype
physical appearance based on allele expression
point mutations
alters a single nucleotide
base substitution
substitute 1 base pair for another
silent
if amino acid stays same, even though DNA sequence is different
missense
if amino acid does change as a result of mutation
nonsense
base change converts codon to stop codon
frameshift mutation
adds or deletes a base from DNA
truncated protein
shortened protein due to base change where a codon is converted to a stop codon
chromosomal mutations
changes the structure of a chromosome
deletions
a portion of the chromosome is lost
duplications
a region of the chromosome is duplicated or repeated
inversions
segment of the chromosome breaks in 2 places, reverses, and is put back together
translocations
a piece of chromosome breaks off and joins another chromosome
sickle cell anemia
result of a base substitution; gene encoding for 1 of hemoglobin polypeptides (a substituted for t)
hemoglobin
protein made up of 4 polypeptide chains and 4 heme groups
heme groups
binds Fe3+ which can bind O2
red blood cells
contain hemoglobin, purpose is to bind O2
“sticky”
hemoglobin becomes hydrophobic and molecules stick together causing RBC’s to develop sickle shape
Point mutations can be…
missense, nonsense, or silent
