DNA and protein synthesis

Question 1

What is the genome?

Answer 1

complete set of genes in a cell

Question 2

What is the proteome?

Answer 2

full range of proteins that a cell is able to produce

Question 3

function/role of mRNA?

Answer 3

-carries genetic code from the DNA to the ribosome
-where its used to make a protein during translation
(made during transcription)

Question 4

structure of mRNA?

Answer 4

• single polynucleotide strand
• complimentary to strand of DNA
• contains uracil instead of thymine
• 3 adjacent bases are called a codon

Question 5

function/role of tRNA?

Answer 5

-carries the amino acids that are used to make proteins to the ribosome
(involved in translation)

Question 6

structure of tRNA?

Answer 6

• single polynucleotide strand that’s folded into a clover shape
• hydrogen bonds between specific base pairs hold the molecules in this shape
• each tRNA molecule has a specific sequence of 3 base pairs -anti-codon- at one end
• it also has an amino acid binding site on one end

Question 7

what is transcription?

Answer 7

production of a single-stranded complimentary copy of a gene = mRNA

Question 8

what is translation?

Answer 8

amino acids are joined together to make a polypeptide chain, following the sequence of codons carried by the mRNA (tRNA) brings the amino acids

Question 9

describe transcription?

Answer 9

1. DNA helicase unwinds the double strand by breaking hydrogen bonds between complementary bases of the gene
   (this leaves some bases exposed on the DNA strand)
2. one strand is used a template for mRNA
   3.complementary RNA nucleotides bind to exposed bases on the template strand
   4.once the RNA nucleotides pair up with specific bases on DNA strand, they’re joined together by RNA polymerase
   - forming an mRNA strand
3. RNA Polymerase joins the sugar-phosphate backbone of the RNA strand

In eukaroyotes

6. leaves pre-mRNA (contains introns and exons)
   - the copies of the introns are removed by splicing
   - Leaves mRNA