mod10 dna replication, protein synthesis & RNA

what is the first step of dna replication and explain the process:

unwinding

2 dna strands begin to seperate catalysed by helices

what is the replication fork:

place where dna begins unwinding

what is step 2 of dna replication: + explain process

synthesis of DNA segments:

synthesis begins as new unwound strands = template for complementary strand

grows from 5’ to 3’

define leading strand:

new dna strand forms by moving towards replication fork

how is leading strand formed:

continuous strands of complementary dna

define lagging strand:

new dna forms away from replication fork

how is lagging strand formed:

little chunks

end result of dna replication:

2 identical dna molecules formed from original

what is the process called for dna replication and why:

semiconservative replication

each dna composed of one old and one new strand

2 steps of protein synthesis:

transcription

translation

differentiate between RNA and DNA:

differences in structure

rna in nucleus, cytoplasm, mitochondria

types of rna; mRNA, tRNA, rRNA

explain transcription:

DNA info coded in mRNA

explain translation:

mRNA decoded to assemble polypeptides

explain primary structure of RNA:

backbone is phosphate-monosaccharide

CGAU bases

explain secondary structure of RNA:

single stranded

fold over itself and base pairs

explain messenger RNA:

carries genetic info from dna to the rest of the cell

explain ribosomal RNA:

makes up 65% of ribosomes

explain transfer RNA:

delivers amino acids from cell cytoplasm to ribosomes so proteins can be synthesised