Nucleotides And Nucleic Acids Flashcards
(22 cards)
Describe the structure of a nucleotide?
Phosphate group
Penrose sugar (a sugar with 5 carbon atoms)
Base
What base isn’t present in RNA but not DNA and what base is in DNA that isn’t in RNA
RNA has uracil
DNA has thymine
What the sugar in DNA nucleotide?
Deoxyribose
What is a pryrimidines and what based are pyrimidines?
One carbon nitrogen rings
Cytosine thymine uracil
What ATP synthesised from?
ADP and inorganic phosphate
(used energy to form)
How do you purify DNA?
Break cells in you sample by blending
Make make up a solution of detergent, salt and distilled water
Add the broken cells
Incubate the beaker in water bath for 60 degrees Celsius for 15 minutes.
Cool in ice bath
Filter mixture with coffee filter paper
Add protease enzymes
Cripple in cold ethanol down side of tube
White precipitation will form that you can hook out
What does DNA helicase do?
An enzyme that breaks the hydrogen bonds between two polynucleotide DNA strands. Unzips helix to form two strands.
What does DNA polymerase do?
Join the the new and old strand together with hydrogen bounds.
What’s a gene?
A sequence of DNA nucleotides that code for a polypeptide.
Properties of genetic code
Non-overlapping-done share bases
Degenerate-more possible triplet combination than amino acids
Universal-same triplet always form same amino acid
Define a gene
A sequence of DNA nucleotides that cold for a protein or polypeptide
What’s the role of mRNA in protein synthesis?
Carries complementary copy of the gene out of nucleus to ribosome
What’s the effect of hydrogen bounds not forming between DNA strands?
The strands will not be join together so will no form a double helix
Give three difference betweeen mRNA and DNA
mRNA-ribose
DNA-deoxyribose
mRNA-one strand
DNA-two strands
mRNA-Uracil
DNA-Thymine
What’s the chemical reaction for ATP?
ADP+Pi=ATP
*energy is used
What is a purine and what bases are purines?
Two carbon-nitrogen rings joined together
Adenine and guanine
Use of DNA
Used to store genetic information (instructions needed for an organism to grow and develop)
What is the use of ADP and ATP?
They are used to store and transport energy.
Define a polynucleotide.
Nucleotides joined together by phosphodiester bonds (ester bounds between the sugar and phosphate). For example DNA.
Whats the structure of DNA?
Two polynucleotide strands that are antiparallele. Twist to form a double helix
What is function of DNA Helicase?
Breaks the hydrogen bonds between the two polynucleotide strands.
What is function of DNA Polymerise?
Joins the strands together
