PROTEIN SYNTHESIS
Proteins are essential to human body: responsible for many processes
● Growing
● Healing
● Forming cell structures
● Carrying oxygen
● Protecting against disease
● Growing hair and nails
● Providing eyesight
● …
↪ proteins are essential for life
TRANSCRIPTION
Food eaten and digested → amino acids and other nutrients from the meal will begin
circulating through the body via bloodstream
↪ amino acids then absorbed into the cells where they will act as a building blocks for new
proteins
TRANSCRIPTION = synthesis of RNA using a DNA template
DNA → “set of instructions” to build any protein it may need
1st step = transcription = production of mRNA using DNA as a template
DNA stored in the cell’s nucleus → where transcription occurs
↪ in prokaryotes it occurs in the cytoplasm
Enzymes involved in the process → RNA polymerase
3 stages of transcription:
1) Initiation: RNA polymerase binds to DNA at the start of the gene. Then it
separates the two strands by breaking the hydrogen bonds, exposing the bases.
2) Elongation: RNA polymerase builds a molecule of mRNA on one of the strands
of DNA. Strand used = template strand (or antisense strand), the other one =
coding strand (or sense strand). The RNA polymerase moves along the DNA
reading it one base at a time, adding free RNA nucleotides to the growing
mRNA.
3) Termination: terminator sequence in the DNA is reached, and the mRNA is
released. RNA polymerase detaches from the strand, and the two join together
again.
, HYDROGEN BONDING & COMPLEMENTARY BASE PAIRING:
RNA polymerase separates the DNA strands by breaking their hydrogen bonds
In DNA → adenine + thymine, cytosine + guanine
↪ RNA polymerase then adds the free RNA nucleotides along the template based on
the complementary base pairing rule. In this case, it pairs uracil (not thymine) with
adenine
Complementary base pairing is essential: correct placement of bases, which make up
the code within the molecule
When correct RNA nucleotide is placed by the RNA polymerase → temporary forms
hydrogen bonds with the DNA template strand
- 2 bonds form with A + T/U
- 3 bonds form between C + G
Proteins are essential to human body: responsible for many processes
● Growing
● Healing
● Forming cell structures
● Carrying oxygen
● Protecting against disease
● Growing hair and nails
● Providing eyesight
● …
↪ proteins are essential for life
TRANSCRIPTION
Food eaten and digested → amino acids and other nutrients from the meal will begin
circulating through the body via bloodstream
↪ amino acids then absorbed into the cells where they will act as a building blocks for new
proteins
TRANSCRIPTION = synthesis of RNA using a DNA template
DNA → “set of instructions” to build any protein it may need
1st step = transcription = production of mRNA using DNA as a template
DNA stored in the cell’s nucleus → where transcription occurs
↪ in prokaryotes it occurs in the cytoplasm
Enzymes involved in the process → RNA polymerase
3 stages of transcription:
1) Initiation: RNA polymerase binds to DNA at the start of the gene. Then it
separates the two strands by breaking the hydrogen bonds, exposing the bases.
2) Elongation: RNA polymerase builds a molecule of mRNA on one of the strands
of DNA. Strand used = template strand (or antisense strand), the other one =
coding strand (or sense strand). The RNA polymerase moves along the DNA
reading it one base at a time, adding free RNA nucleotides to the growing
mRNA.
3) Termination: terminator sequence in the DNA is reached, and the mRNA is
released. RNA polymerase detaches from the strand, and the two join together
again.
, HYDROGEN BONDING & COMPLEMENTARY BASE PAIRING:
RNA polymerase separates the DNA strands by breaking their hydrogen bonds
In DNA → adenine + thymine, cytosine + guanine
↪ RNA polymerase then adds the free RNA nucleotides along the template based on
the complementary base pairing rule. In this case, it pairs uracil (not thymine) with
adenine
Complementary base pairing is essential: correct placement of bases, which make up
the code within the molecule
When correct RNA nucleotide is placed by the RNA polymerase → temporary forms
hydrogen bonds with the DNA template strand
- 2 bonds form with A + T/U
- 3 bonds form between C + G
