types of RNA and protein synthesis

Question 1

what are the 3 main types of RNA

Answer 1

-mRNA messenger RNA
tRNA transfer RNA
-rRNA ribosomal RNA

Question 2

describe mRNA

Answer 2

-made in the nucleus
-carries a copy of gene from DNA to a cytoplasm to make proteins during translation

Question 3

describe tRNA

Answer 3

-found in cytoplasm
-has amino acid binding site one end
-sequence of 3 bases at the other end -anticodons
-carries amino acids to make proteins at ribosomes during translation

Question 4

describe rRNA

Answer 4

-made in nucleus
-forms two subunits in a ribosome
-helps to catalyse formation of peptide bonds between amino acids

Question 5

explain the process of transcription

Answer 5

1. gene unwinds by DNA gyrase
2. DNA helicase breaks hydrogen bonds between nucleotide bases exposing bases on template strand
3. free RNA nucleotides hydrogen bond to exposed DNA bases (complimentary)-uracil instead of thymine
   4.RNA polymerase catalyses formation of phosphodiester bonds between RNA nucleotides
4. length of mRNA is produced complimentary to template strand, copy of coding strand
   6.mRNA leaves through nuclear pore and attaches to ribosomes

Question 6

explain translation

Answer 6

1. small subunit of ribosome binds with mRNA
2. tRNA with complimentary anticodon hydrogen bonds to mRNA base bringing amino acids
3. peptide bonds are formed between the amino acids on tRNA (catalysed by peptidyl transferase, requires ATP)
4. this continues down the mRNA until stop codon and polypeptide is formed which detaches and is folded to carry out its function