Lecture 32 Flashcards
covalent structure and nucleotide sequence , what structure
primary structure
regular, stabel structure taken up by some or all the nucleotides
secondary structure
complex folding of large chromosomes or the elaborate folding of tRNA or rRNA structures
tertiary structure
covalent bond that joins successive nucleotides of both DNA and RNA
phosphodiester linkage
phsophodiester bonds are between what and what
5 prime and 3 prime
3’, 5’ - phosphodiester bonds run in the same direction
parallel
3’, 5’ phosphodiester bonds run in opposite directions
antiparallel
antiparallel confirmed how
by x ray analysis
how many H bonds between G and C
3
how many H bonds between A and T
2
3 H bonds between what
G and C
2 H bonds between what
A and T
G = what
c
A = what
T
which base pairing tends to be the strongest and why
guanine cytosine due to more H bonds
has the potential to form hairpin or cruciform
palindrome
no possibility of self complementarity
mirror repeat
which pairs with itself
hairpin
palindrome has potential to form what
hairpin or cruciform
three different DNA forms
a form, b form, z form
more common in solutions lacking water; unknown how frequently it may occur in cells
a form
common in physiological conditions, what form
b form
which form is Watson and crick associated with
b form
common when C-G pairs are alternating; found in some cells but function is unknown, what form
z form
non- Watson crick pairing, what type
Hoogsteen pairing
form from Hoogsteen pairing
triplex DNAs
occur when 4 DNA strands pair
tetraplex DNA
most stable tetra plex
g tetraplex
occur readily only for DNA sequences with high prop of G residues
tetraplex DNA
mRNA is always what
single stranded
is mRNA right or left handed conformation
right
can base pair with complementary regions of DNA or RNA
mRNA
paired strands of mRNA are what
antiparallel
what are breaks caused by in RNA
mismatched or unmatched bases
what do breaks result in for RA
bulges or internal loops
internal loops form between..
palindromic sequences
primary location containing all genetic material
nucleus
what is DNA organized into in the nucleus
chromosomes
what are smaller than the nuclear chromosomes
mitochondria
mitochondrial codes for what
mitochondrial tRNA, rRNA, some mitochondrial proteins
all the DNA the encodes the primary sequence of some final gene product
gene
one protein is prod from one gene, what hypoth
one gene-one polypeptide hypothesis
non translated DNA
introns,
translated DNA (coding DNA) called what
exons
3 consecutive nucleotides in a single strand of DNA the codes for a specific amino acid
codon
how is DNA present in bacteria,
plasmid compacted in the nucleoid
small, circular DNA molecules that are in the cytosol of many bacteria
plasmids
consist of just a single RNA or DNA molecule and a protein coat
viruses
viruses mostly contain what
RNA
are viruses living or nonliving
nonliving
eukaryotic chromosomal material composed of DNA, RNA and proteins
chromatin
tertiary packaging of DNA
chromosomes
enzymes that inc or decrease the extend of DNA underwinding
topoisomerases
DNA sequence that functions during cell division as an attachment point for proteins that link the chromosome to the mitotic spindle
centromere
sequences at the ends of eukaryotic chromosomes that help stabilize the chromosome
telomeres
proteins that are tighly associated with chromatin
histones
function to package and order the RNA
histones
histones tend to associate with regions rich in what
A/T
proteins that package DNA
histones
fundamental structural unit of chromatin
nucleosomes
chromosomes are what before cell division
highly condensed and organized
phase where genetic material replicated
s phase
which strand synthesizes in segments
lagging
catch potential mistakes in nucleotides
proofreading
ends where 3’ C is free
3’ end
3’ end ends where
3’ C is free
5’ ends where
5’C is only bound to phosphate, not another base pair
4 func of DNA polymerase
- incorporates dNTPs, proofreads, replaces RNA primers with DNA 4. puts Okazaki fragments together
