Exam 3 Flashcards
centrioles
organize microtubules that form spindle (called and aster)
-not in plants
Why Mendel’s ratios work
- segregation- discrete units, genes don’t blend
- independent assortment- characteristics are separate (color and shape)
- dominance
Why Mendel’s ratios don’t work??
- incomplete dominance- red+white flower = pink
- multiple alleles - Co-cominance of multiple alleles- A can be dominant and B can be dominant
- enviormental factors and polygenetic
polygenic inheritance
multiple gene loci are involved in controlling phenotype of trait
- more than one gene for trait
- height (range)
pleiotropy
a single gene affects more than one trait
-sickle cell anemia
epistasis
product of 1 gene interacts with another
-pigment and enzymes interacting
Meselson and Stahl
N14 and N15 put bacteria in concentrations and see how often replicating by ultracentric fugation
- 1 band after 1, 2 bands after 2
- semiconservative replication is used for DNA
ultracentric fugation
spin solution and heavy goes to bottom
elongation
new strands of DNA are synthesized by DNA polymerse; make complimentary strands
replication fork
DNA splits in half
helicase
opens up helix (uncoils)
-leading and lagging strand
gyrase
relieves tension created by helicase
-leading and lagging strand
single-stranded binding proteins
brings DNA back together when separated
-leading and lagging strand
p site
binds the tRNA attached to the growing peptide chain
point mutations
alter a single base
base modification/deletion
deleting a single base causing a frame shift
-point mutation
biotechnology
alternating DNA to create what we want
- cut DNA with enzyme- restriction endonucleus
- separate DNA fragments by gel electrophoresis by size
- add recombinant (GMO) vector to a new cell
vector
plasmid or small double stranded circles of DNA
recombinant plasmid
recombine DNA; foreign DNA in vector
crown gall disease
- dicots
- bacterium has tumor inducing plasmid
- bacteria T-DNA in plant nucleus that then gives hormones that cause gall
introns
taken out by SNRPS (non coding areas)
exons
coding parts left behid
SNRNPS
do the work of cutting and splicing
antisense RNA
hydrogen bonds with mRNA so translation and transcription can’t happen
anticodons
are the codes which match a complimentary region on the mRNA so that amino acids are assembled in the proper order
