Nucleic Acids Flashcards
what is a nucleic acid
large polymers made of nucleotides
what elements are nucleic acids made of
carbon, hydrogen, oxygen, phosphorus, nitrogen
give 2 types of nucleic acids
DNA & RNA
RNA stands for
ribonucleic acid
name 4 organic bases
adenine, cytosine, thymine, guanine
what part of the nucleotide contaisn nitrogen
nitrogenous organic base(s)
name 3 properties of phosphate group in nucleotide
- inorganic molecule
- acidic
- negatively charged
what ion within phosphate group & ribose sugar are these 2 molecules bonded between>
OH group from phosphate & 5’ carbon or 3’ (depending on strand direction) from pentose sugar
what bond is in between phosphate group & pentose sugar
phosphodiester bonds
what bond is in between pentose sugar and nitrogenous base
glycosidic bonds
name the 2 categories for bases
purine bases & pyrimidine bases
what bases are purine
A & G
what bases are pyrimidine
T & C
how many rings do purine baes have? pyrimidine?
purine = 2 rings pyrimidine = 1 ring
how many bonds between A - T? And what type of bond?
2 hydrogen bonds
what bond is in between organic bases from 2 nucleotides?
hydrogen bonding
how many bonds between G - C
3 hydrogen bonds
when is uracil coded instead of thymine
For the RNA during transcription in the nucleus during protein synthesis
Who is credited with the double helix theory of DNA
Watson & Crick
what technique was used to prove double helix DNA theory?
X-Ray diffration techniques
where can DNA also be found in a eukaryotic cell?
mitochondria & chloroplasts
prokaryotes & viruses have —– DNA, fill in gap & describe what it is
naked DNA, looped DNA (1) that’s not associated with histone protein (1)
describe the composition structure of DNA in one sentence
made up of 2 strands of polynucleotides (1) held together by hydrogen bonds between nitrogenous bases (2)
name 2details about DNA’s structure
antiparallel, double-stranded helix,
define what is meant by antiparallel (DNA structure)
strands run in opposite directions, for 1 strand base is connected to carbon 3’ on pentose sugar, the other strand on carbon 5’
ngive 2 reasons why DNA is in a double helix structure
more compact & gives molecule structure
what is the reaction called that joined together the 2 polynucleotide chains
condensation reaction
name 4 properties of RNA that make it different from DNA
- single polynucleotide strand
- small & passes through nuclear pore
- ribose instead of deoxyribose
- uracil base instead of thymine
what are the 2 DNA strands technical terms?
polynucleotide chain
name the 5 enzymes used in DNA replication
helicase, gyrase, DNA binding proteins, DNA polymerase, DNA ligase
helicase function
unzips the 2 DNA strands using energy from ATP
DNA binding proteins function
seperates polynucleotide stands during replication
DNA polymerase function (2)
- joins nucleotides to form the polynucleotide chain in the 5’ to 3’ direction
- proofread & corrects mistakes in base pariing
gyrase function
unwinds double helix
DNA ligase function
On the lagging strand, DNA ligase joins together the short sections of nucleotides polymerase by DNA polymerase in the 3’ to 5’ direction.
name 2 things that can cause DNA mutations
- spontaneous errors in replication
- radiation & MUTAGENIC chemicals
semi-conservative replication explanation
(1) 2 molecules with 1 original strand & 1 new DNA strand, - a hybrid strand
(2) original strand acts as a template for new strand
what is the genome
the entire genetic material aka all the DNA in a cell’s nucleus of an organism
true or false an organisms genome changes over time?
false
why are detergents used to extract DNA (PAG)
to dissolve the nuclear & cell membrane to release DNA
why is ethanol used to extract DNA (PAG)?
Causes DNA to precipitate & form a white mucous
why is the ethanol used to extract DNA kept cold
increases the yield of DNA. Low temperatures protect the DNA by slowing down the activity of enzymes that could break it apart
how can amount of DNA samples be compared
compare the mass of DNA collected
why is salt used in DNA extraction?
salt neutralizes the charge of the DNA’s sugar-phosphate backbone, making DNA less hydrophilic
why is protease used in DNA extraction
breaks down glycoproteins on cell membrane creating temporary holes in membrane large enough to allow DNA to pass through
name 4 features of genetic code
degenerate, universal, non-overlapping, triplet code
what is the genetic code
the relationship between bases & amino acids during protein synthesis at the ribosome
degenerate meaning (genetic code)
an amino acids can be coded for by more than 1 type of codon
universal meaning (genetic code)
all organisms use the same bases (A, T, C, G) just in a different order
non-overlapping meaning (genetic code)
no single base can take place in the formation of more than 1 codon
true or false more than 1 type of codon can code for the same amino acid
true
technical term for coding sections of DNA
exons
technical term for non-coding sections of DNA
introns
what is the advantage of genetic code being degenerative
reduces the chance of random & spontaneous mutations to impact the proteins function
transcription definition
- the process of making mRNA from a DNA template (using complimentary base pairing)(1)
- to be transported out of the nuclear (2)
- to the site of protein synthesis (3)
translation definition
formation of a protein at ribosomes by assembling amino acids into a particular sequence according to mRNA instructions
what is the role of mRNA in protein synthesis & include the full form
messenger RNA - transports amino acid sequence of proteins
what is the role of tRNA in protein synthesis & include the full form
transfer RNA - transports 3 bases to ribosomes for complementary pairing with mRNA
what is the role of rRNA in protein synthesis & include the full form
ribosomal RNA - combines with protein to form a ribosome for protein synthesis
True or False, glucose heps to make ATP
true
what are the components of ATP?
adenine, ribose (pentose) sugar, 3 phosphate groups
what is full name of ATP
adenosine triphosphate
phosphorylated nucleotides meaning
nucleotides that contain more than 1 phosphate group e.g ATP & ADP
what is a nucleoside & give an example
nitrogenous base + pentose sugar, NO PHOSPHATE GROUP, e.g adenosine
name 3 properties of ATP
small, water soluble, easily regenerated
what is ATP regernation
ADP + phosphate group; NEEDS ENERGY TO REGENERATE
what is the ATP energy-releasing reaction called & word formula
hydrolysis reaction - ATP + H2O —> ADP + PO4
what is the formula of a phosphate group and what is its charge
PO4 & -3 charge
what is the difference in a scenario between DNA replication & transcription?
DNA replication occurs in prep for cell division for 2 new daughter cells. Transcription occurs for mRNA protein synthesis.
PAG) what is the process called that purifies DNA from a fruit?
precipitation
PAG) what chemical is used in DNA precipitation? Why
Ethanol: causes DNA to precipitate out of plasma membranes
True or False nucleic acids have a charge? why & is it -ve or +ve
True, phosphate groups cause nucleic acids to be slightly negative
PAG) why is DNA solution incubated at 60 degrees
To denature enzymes & proteins on the membranes = increases permeability
and increase the fluidity of phospholipid bilayer to create temporary pores
PAG) what is the DNA solution called?
extraction buffer
PAG) why is DNA solution not incubated higher than 60 degrees
So DNA itself doesn’t denature, causing DNA to unwind & separate into 2 strands
where is deoxyribose bonded to in the nucleotide of DNA
bonded / joined / attached , to base and
phosphate ; phosphate (joined) to C5 (and C3)
& base (joined) to C1
describe how polynucleotides are formed and broken down?
condensation reactions between nucleotides form strong phosphodiester bonds, forming a sugar-phosphate backbone.
how is genetic material conserved accurately after replication
with specific base pairings
how would you descibe a mutation
spontaneous and random
