Biological molecules part 2 Nucleic acids,water, ATP, ions Flashcards
what is the function of DNA
to store genetic information
what is the function of RNA
to transfer genetic information from DNA to ribosomes
what are the monomers of DNA and RNA
nucleotides
what is the structure of a DNA nucleotide
dexoyribose-pentose sugar
nitrogen containing organic base A,T,G,C
phosphate group
what is the structure of an RNA nucleotide
ribose-pentose sugar
nitrogen containing organic base A,U,G,C
phosphate group
what are the four organic bases in RNA
Adenine guanine cytosine uracil
outline the structure of an RNA molecule
single stranded short polynucleotide chain
what are ribosomes comprised of
proteins and RNA
which scientists in 1953 discovered the structure of DNA
James Watson and Francis Crick
outline the structure of a DNA molecule
Long double stranded
polynucleotide chain
strands joined together by hydrogen bonds
what bond is found between two nucleotides joined together via a condensation reaction
the bond between two nucleotides joined together
via condensation reaction is a phosphodiester bond
what are the four requirements for semi-conservative replication to take place
the four types of nucleotides and bases must be present
both strands of DNA act as a template for attachment of the nucleotides
the enzyme DNA polymerase
A source of chemical energy required to drive the process
outline semi conservative DNA replication
DNA helicase breaks the hydrogen bonds between the complimentary base pairs
double helix seperates into it’s too strands and unwinds
exposed polynucleotide strands act as templates for complimentary base pairing with complimentary free nucleotides that bind by specific base pairing
nucleotides are joined together via DNA ploymerase which reforms the sugar phosphate backbone
how is DNA replication semi conservative
each of the new DNA molecules contains one of the original strands half of the original DNA strand is in the new molecules
outline the structure of ATP
adenine
ribose
a chain of three phosphate groups
how does ATP store energy
bonds between phosphate groups unstable
hydrolysis of bonds between phosphate groups
low activation energy
when broken release considerable amount of energy
what enzyme catalyses the hydrolysis of ATP to ADP
ATP hydrolase
what enzyme catalyses the synthesis of ATP from ADP and Pi
ATP synthase
what are three ways ATP is synthesised
photo-phosphorylation in photosynthesis
during respiration- oxidative phosphorylation
substrate level phosphorylation
what can the inorganic phosphate released from ATP hydrolyses be used for
the phosphorylation of other molecules making them more reactive
name two important roles of water in reactions
as a solvent
as a metabolite
outline waters role as a metabolite
it is a metabolite in reactions such as condensation and hydrolysis
outline waters role as a solvent
some substance can dissolve in it which is good as metabollic reactions take place in solution
how can water help with temperature control
due to high specific capacity
high latent heat of vaporisation
what does water being cohesive help with
transport in plants as well as other organisms
what allows water to help with temperature control and gives it’s other useful properties
the hydrogen bonding located in the water
name two inorganic ions and descrive their roles in the body
iron ions in hameoglobin
they allow oxygen to bind to hameoglobin
sodium ions
allow glucose and amino acids to be absorbed into the blood via co-transport into cells
what is an inorganic ion
an ion that does not contain carbon
where do inorganic ions occur
in solution
in cytoplasm of cells
and body fluids of organisms
why do the two strands of DNA run antiparallel to each other?
as DNA polymerase is complimentary to the 3’ end of the newly formed DNA strand
so enzyme can only add nucleotides to new strand at 3’ end
why is water a polar molecule
it has a sligh negative charge on one side and a slight positive charge on the other
