test 2 Flashcards
what is autosomal dominent
the allele for the trait is dominant and is carried on an autosome
what is autosomal recessive
the allele for the trait is recessive and is carried on an autosome
what is x linked recessive
the allele for the trait is recessive and is carried on the sexual chromosome x
what is x linked dominant
the allele for the trait is dominant and is carried on the sexual chromosome x
what is transcription and what do you get
the process of converting DNA to RNA
from a template strand from 3’ to 5’, you get a complementary strand from 5’ to 3’
what is translation and what do you get
translation is the process of converting RNA to a protein (comes after transcription)
from a complementary strand you get a protein of the form
N Met-Pro C
what are the letters changing to in transcription
A to U
C to G
G to C
T to A
what is the orientation of mRNA (messenger)
always 5’to3’
when translating mRNA what do you get
protein
what is a missence mutation
-type of base substitutions
-alters the identity of the amino acid
-effects the reactive site of enzymes (moderate effects)
what is a nonsense mutation
-type of base sub
-generates an early stop codon so protein is truncated
-has severe effects on protein function
silent mutation
-type of base sub
-generates no change because protein identical so does not have an effect
what are frameshift mutations
-insertions or deletions
-changes the reading frame
-the remainder of the protein after is changed
-a premature stop codon will end translation
what is a deletion in Large chromosomal rearrangement
-occurs if a broken segment is lost from a chromosome
-ex: deletion on human chromosome 5 normally leads to severe cognitive impairment and a malformed larynx (cris du chat)
what is a duplication
-type of large chromosomal rearrangements
-a segment is broken from one chromosome and added to its homologue
-in the receiving homologue the alleles of the inserted fragment are added to the ones already there
-may be good or bad depending on the genes and or alleles in the duplicated region
-ex: mammals have genes that encore several types of hemoglobin that are not present in vertebrates such as sharks that evolved earlier
what is a translocation
-type of lcr
-occurs when a segments of a chromosome breaks and attaches to another non-homologous chromosome
-ex: cancer burkitt lymphoma happens in humans when part of chromo 8 goes to the end of chromo 14
what is an inversion
-type of LCR
-part of a chromo breaks and reattaches on the other side
-ex 5 human chromo show signs oof inversions that our nearest relative the gorilla doesn’t have so is a big part of evolution
what are transcription factors
proteins that need to bind to DNA and regulate gene expression by promoting or suppressing transcription to recruit rna polymerase II
what is the difference in the mRNA of eukaryotes and prokaryotes
eukaryotes have pre-mRNA that needs to be transformed to go through translation
prokaryotes have their rna ready to go from transcription to translation
there are no transcriptionfactors in prokaryotes
what is epistasis
many genes that interact with each other where one or more alleles of one gene can mask the effect of other genes
what is incomplete dominance
both phenotypes show up to create a new one (pink flower from a red and a white)
what is codominance
both phenotypes are expressed
what is a lethal recessive allele
-phenotype for heterozygous individual is normal
-lethal for homozygous individual
f2 ratio 3:0
what are multiple alleles
small differences in the sequence of the DNA at one or more points of a gene