D1.1 1.2 Tutor

Nucleotides is the

building blocks of nucleic acid

three major examples of nucleic acids in nature

ATP, DNA, RNA

Nucleotide components

Phosphate group

Deoxyribose (for C2 only H no O)

Nitrogenous base

Guanine and cytosine are held together by ________hydrogen bonds.

3

Adenine and thymine are held together by ________ hydrogen bonds

2

Categories of bases

Pyrimidine - Single carbon ring - CT

Purine: double carbon ring - AG

who is Erwin Chargaff

person came up with the Structure of dna

how to find leading strand

Look at parent strand only

3’ to 5’

Towards the replication fork

lagging must synthesized from

5’ to 3’

Mutation

Permanent change in bases of DNA - ATCG

Sense Strand

mRNA sequence (with codon), replace all T with U;

Antisense Strand

Anticodon, replace all T with U

if question gives sense strand - what is mRNA

exact same as sense but replace t with u

if question gives antisense strand - what is mRNA

complementory base pairing

What is the anticodon

It is the same as antisense strand, replace t with u

Sense strand contains the gene to code for protein. But which strand is really

being transcripted?

antisense strand

If dont tell if its a sense strand - then assume its

antisense strand

sense anti mRNA direction

5’ - 3’

3’ to 5’

5’’ to 3’

DNA replication and Transcription both go from the _____' to ______' direction.

5’ to 3’

Codon

triplet base

human how many amino acid

20

Two important aspect of genetic code

Universality = apply to almost all organisms (not for bacteria cuz they have little bit more amino acid)

Degeneracy = more than 1 codon code for the same amino acid

genetic code =

illustrate the relationship between the mRNA codon and the amino acid

Amino acid comes first or after translation

first

amino acid/anticodons are already combined with the tRNA before they come into the ribosome to bind to the codon on the mRNA.

Ribosome

the structures where polypeptides (proteins) are built. They are made up of protein and rRNA (ribosomal RNA). Each ribosome has two subunits, a large one on top and a small one underneath, which come together around an mRN

how many binding sites on ribosome

4 - 1 for mRNA and 3 for tRNA

three stages of translation

Initiation, elongation, termination

if need detail of initiation…

tbd

why is dna replication important

Repair

Organism growth

Embryonic development

dna replication is a form of

mitosis - asexual - identical