2.1.3 nucleotides and nucleic acid Flashcards
what does a nucleotide consist of
2.1.3(a)
a pentose sugar
phosphate group
nitrogenous base
what are nucleotides the monomer for
2.1.3(a)
nucleic acid
what is deoxyribose
2.1.3(a)
the pentose sugar found in DNA nucleotides
which ones are purine bases
2.1.3(a)
adenine and guanine
2 carbon and nitrogen based rings
which ones are pyrimidine bases
2.1.3(a)
Thymine and cytosine
1 carbon and nitrogen based ring
what is the difference between the pentose sugar in RNA vs DNA
2.1.3(a)
RNA-ribose (OH group)
DNA-deoxyribose (H group)
where is thymine and Uracil present
2.1.3(a)
thymine-DNA
Uracil-RNA
what is a phosphodiester bond
2.1.3(b)
bond between phosphate group and pentose sugar
how many pentose sugars is one phosphate group able to join to
2.1.3(b)
one phosphate group is able to bind to two pentose sugars
when is the sugar phosphate backbone of the nucleotide formed
2.1.3(b)
the pentose sugars are joined to each other by bonds with the phosphate groups
what are ADP and ATP and what do they contain
2.1.3(c)
ATP and ADP are RNA nucleotides containing the nitrogenous base adenine
what does the A in ADP and ATP stand for
2.1.3(c)
adenosine, which is what we call adenine bonded to a ribose
what does the P stand for in ADP and ATP
2.1.3(c)
phosphate
what is ATP and what does it contain
2.1.3(c)
adenosine triphosphate = adenine + ribose + three phosphate groups
what is ADP and what does it contain
2.1.3(c)
adenosine diphosphate = adenine + ribose + two phosphate groups
what is AMP and what does it contain
2.1.3(c)
adenosine monophosphate = adenine + ribose + one phosphate group
what do ATP ADP and AMP provide
2.1.3(c)
they provide the immediate source of energy for every cellular process that requires energy
what is the reaction that releases energy from ATP called
2.1.3(C)
The reaction that releases energy from ATP is hydrolysis, which also removes inorganic phosphate groups (Pi) to form ADP or AMP
what is the purpose of respiration
2.1.3(c)
to make ATP
draw the ATP/ ADP cycle
2.1.3(C)
in booklet
what is the polymer DNA made up of
2.1.3(di)
nucleotide monomers bonded together via phosphodiester bonds formed during condensation reaction
what is a molecule of DNA made out of
2.1.3(di)
two polynucleotide strands
since the two strands run in opposite directions what are they described as
2.1.3(di)
anti parallel
since a DNA molecule is long what can it store a lot of
2.1.3(di)
genetic information
what is the shape of DNA
2.1.3(di)
double helix as it consists of two strands spiralling in a helix shape
what are the bonds between nitrogenous bases
2.1.3(di)
hydrogen bonds
what are the complementary base pairs in nucleotides and what hydrogen bonds do they have between them
2.1.3(di)
adenine and thymine- two hydrogen bonds
guanine and cytosine-three hydrogen bonds
what would the strand be bonded to if it was
5’ to 3’
3’ to 5’
2.1.3(di)
the next nucleotide would be bonded to the OH group on C3
the next nucleotide would be bonded to the phosphate group on C5
what are the steps for DNA extraction
2.1.3(dii)
- blend/grind - break down the cell walls if they are present e.g. plant or fungi cells (not needed for animal cells)
- Add salt - break hydrogen bonds between DNA and water molecules
- Add detergent - dissolve the plasma membrane and nuclear envelope
- Add protease enzyme to hydrolyse histone proteins
- Add ethanol to precipitate the DNA. DNA is not soluble in ethanol so it will come out of solution forming a stringy white solid and can be collected.
describe how you get 2 DNA molecules that are identical to eachother
2.1.3(e)
- The DNA molecules is untwisted out of its double helix shape by the enzyme DNA gyrase
- DNA helicase breaks hydrogen bonds between nitrogenous bases leaving 2 single strands of DNA with exposed bases
-DNA nucleotides present in the nucleoplasm hydrogen bond to exposed base pairs following the complementary base pair rule - DNA polymerase catalyses the formation of phosphodiester bonds between free nucleotides in the 5’ to 3’ direction
-if the new strand being made runs in the 3’ to 5’ direction DNA polymerase falls off and DNA ligase joins the short sections
why is a DNA molecule semi-conservative
2.1.3(e)
each DNA molecule contains one original strand and one new strand
what are alleles
2.1.3(e)
different versions of the same gene
what is the triplet code
2.1.3(f)
three bases called a codon code for one amino acid
what does it mean if the genetic code is universal
2.1.3(f)
a certain codon codes for the same amino acid in all living organisms
what does it mean if the genetic code is non-overlapping
2.1.3(f)
each base only belong to one codon
what does it mean if the genetic code is degenerate
2.1.3(f)
where a different sequence of bases code for the same amino acid
what are the steps to transcription
2.1.3(g)
· A gene untwists by the enzyme DNA gyrase and hydrogen bonds between complementary base pairs are broken by DNA helicase
· Free RNA nucleotides that are complementary to the template strand form hydrogen bonds to the template strand
RNA polymerase catalyses the formation of phosphodiester bonds between the free RNA nucleotides
· mRNA is made
what are the steps to translation
2.1.3(g)
mRNA moves out of the nucleus via a nuclear pore and attaches to a ribosome
· The anticodon of a tRNA molecule forms hydrogen bonds to the complementary codon on the mRNA
· The tRNA is carrying a specific amino acid, determined by its anticodon
· tRNA molecules line up, and an enzyme catalyses the formation of peptide bonds between the amino acids they are carrying
· After the polypeptide has been assembled, it is released from the ribosome and the mRNA breaks down over time
which strand is used to make mRNA
2.1.3(g)
template strand not the coding strand
is the mRNA complementary to the coding strand
2.1.3(g)
yes except the T is replace with U on the mRNA
