2.3 DNA/nucleotides Flashcards by Sophie Hank

what is a nucleotide made of

nitrogenous base
phosphate group
5 carbon sugar (deoxyribose)

How well did you know this?

Not at all

Perfectly

name the functions of a nucleotide

monomer of nucleic acids
become phosphorylated when contain more then one phosphate group
regulate metabloic pathways
components of coenzymes

How well did you know this?

Not at all

Perfectly

explain the difference between AMP, ADP, ATP

AMP= one phosphate group adenosine monophosphate
ADP= two phosphate groups
adenosine diphosphate
ATP= three phosphate groups
adenosine triphosphate

How well did you know this?

Not at all

Perfectly

what is a phosphoryolated nucleotide and name two examples

a nucleotide thats had phosphates added to it
ADP , ATP

How well did you know this?

Not at all

Perfectly

what is DNA

macromolecule that makes up the structure of living organisms

How well did you know this?

Not at all

Perfectly

describe the structure of DNA

polymer made of nucleotides in two strands that run in opposite direction (antiparalell)
phosphodiester bond between sugar and phosphate group
double helix

How well did you know this?

Not at all

Perfectly

name the two types of nucleotides based off bases

purines
pyrimidines

How well did you know this?

Not at all

Perfectly

desribe the difference between a purine and pyrimidine

purine= two rings
pyrimidine= one ring

How well did you know this?

Not at all

Perfectly

what bases are a purine

adenine
guanine

How well did you know this?

Not at all

Perfectly

what bases are a pyrimidine

thymine
uracil
cytosine

How well did you know this?

Not at all

Perfectly

how many hydrogen bonds form between adenine and thymine

How well did you know this?

Not at all

Perfectly

how many hydrogen bonds form between cytosine and guanine

How well did you know this?

Not at all

Perfectly

how are polynucleotides made and broken

forming and breaking phosphodiester bonds

How well did you know this?

Not at all

Perfectly

what is the role of hydrogen bonds in DNA

form between the bases on two anitparallel DNA strands

How well did you know this?

Not at all

Perfectly

what is the importance between purines and pyrimidines

purine always joins a pyrimidine so there is equal sized rungs on the DNA ladder
twists into double helix

How well did you know this?

Not at all

Perfectly

how does DNA replicate

enzyme gryase unwinds/ helicase unzips DNA double helix by breaking hydrogen bonds on antiparallel strands
dna polymerase - free phosphorylated nucleotides and bonds with the exposed bases
energy released and used in next reaction to form bonds

How well did you know this?

Not at all

Perfectly

what is the product of DNA replication

two DNA molecules identical to another
each containing one strand of original DNA and newly replicated DNA

How well did you know this?

Not at all

Perfectly

why is DNA replication semi conservative

semi=half
contains one strand from original and one replicated

How well did you know this?

Not at all

Perfectly

define universal for the nature of genetic code

in all organisms the same triplet of DNA bases codes for same amino acid

define degenerate

for all amino acids there is more then one base triplet so amino acids can be coded for by multiple codons

define non overlapping

genetic code/bases are only read from a fixed point in groups of 3

what does the order of bases result in

the codon = the amino acid = order of amino acids = shape of protein

what is RNA made of

nucleotides
ribose sugar
nitrogenous base (AUCG)
phosphate group

what are the three forms of RNA

mRNA
tRNA
rRNA

what is mRNA

messanger RNA

what is tRNA

transfer rna

what is rRNA

ribosomal RNA

what happens in transcription

DNA is transcribed and an mRNA molecule is produced

what happens in translation

mRNA (messenger RNA) is translated and an amino acid sequence is produced

steps of transcription

gryase and helicase unwinds and unzips DNA RNA polymerase catalyses the formation of temp. hydrogen bonds between free RNA nucleotides and DNA bases copy of strand produced mRNA leaves the nucleus

steps of translation

tRNA binds to complementary triplet has amino acid peptide bond forms

what direction does RNA polymerase move in

3' to 5' direction

what direction does mRNA move/grow in

opposite to RNA polymerase 5' to 3' direction

what is the template strand

strand of DNA used to produce the mRNA molecule

what is the coding strand

length of RNA bases that are complementary to the template strand

where does transcription and translation occur

-scription = nucleus -slation= cytoplasm

describe the structure of tRNA

hairpin shape anticodon at one end = triplet of unpaired bases complementary to mRNA triplet of bases at other end where amino acid attaches

what is the role of tRNA

bind with their specific amino acids and bring them to the mRNA molecule on the ribosome

what bond forms between amino acids as tRNA binds to the mRNA strand

peptide bonds

how does translation stop

process continues until stop codon on mRNA is reached and final polypeptide chain forms

name the steps in DNA purification

grind with pester and mortar add salt add detergent add protease place in water bath filter into beaker/tt tilt and poor in ice cold ethanol

when purifying DNA why do you crush sample with pestle and mortar

to break open cell wall

in DNA purification what enzyme do you need to use and why

protease to break down histone proteins associated with DNA

why do you add detergent (DNA purification)

to break down phospholipid bilayer

why is ethanol added

to precipitate DNA (white layer forms)

why is salt added

helps DNA precipitate/ shed water

explain what the experiment with isotopes of nitrogen show and support semi conservative replication

tube 1 shows DNA / band contains light nitrogen and heavy nitrogen tube 2 DNA / band, made from only, light nitrogen so strand of DNA must be a template tube 10 highest band more of the DNA is made from only, light nitrogen