IB Lifeline : Transcription and Translation

DNA Transcription: RNA produced using a DNA template

RNA polymerase used to separate the double DNA strands into an anti-sense strand and a sense strand. A complementary RNA strand is synthesized by copying the anti-sense DNA strand. The produced RNA strand will be the same as the sense strand with the exception of uracil which replaces thymine (Uracil is paired up with adenine instead).
Nucleotides line up opposite their complementary base on the DNA strand and the two bases are covalently bonded.
RNA polymerase can detach from the DNA strand, and the two DNA strands will reform
The RNA that is transcribed is called a gene. This happens in the nucleus before moving out into the cytoplasm.

Main types of RNA:

Genetic Code:

The genetic code is a universal code that can be used to synthesize the same proteins in all organisms with the exception of a few rare codes.
Codons consist of three bases that codes for a specific amino acid. The four different bases create 64 possible combinations of codons
Codons are used to determine the order of amino acids found in a protein
A start codon using the bases AUG will begin the translation process. There will also be a specific codon which identifies when to stop.
There are only 20 amino acids which are coded by 64 codons. Sometimes multiple codons will code for the same amino acid. Mutations to some codons will not affect the polypeptide sequence since a different codon can replace it and code for the same amino acid anyways.

Translation:

Initiation: assemble ribosomal complex

Elongation: Amino acids delivered to ribosome in order of codons

Translocation: amino acids added/bonded to polypeptide chain

Termination: Stop codon on the mRNA is reached and trnaslation is terminated, polypeptide released.

Genetic information found in mRNA is used to sequence a polypeptide chain of amino acids
Ribosomes found in the cytoplasm will bind to 5' end of mRNA. When it reaches the start codon (AUG) , the translation process will begin moving toward the 3' end of the RNA. Ribosomes help to catalyse the peptide bonds that form between amino acids through a condensation reaction. Ribosomes also stabilize the rRNA. Ribosomes are made of two subunits, one that is small where the mRNA will bind, and the large subunit on top where tRNA can bind.
Enzymes are used to activate tRNA molecules by recognizing the unique shape and chemical composition of the tRNA. The enzyme will bind ATP to the amino acid to create an amino acid-AMP complex. The amino acidis brought to the 3' end of the tRNA and releases the AMP molecule. The tRNA molecule is now 'charged' and can be translated. The energy found in the ATP can be used in translation to form the pdptide bonds between amino acids.
Anticodons attached to tRNA molecules will match up with their complementary codons depending on the base pairs. This tRNA will carry the amino acid that corresponds to the codon.
The ribosome moves the mRNA as the polypeptide chain is created. The mRNA reaches the stop codon and translation is stopped and the protein is released.

Transcription in Prokaryotes:

Promoter binds to the RNA polymerase and unwinds the DNA strands. Many RNA polymerase can transcribe the DNA at the same time.
Nucleoside triphosphates will match with the complementary bases of the anti-sense strand
RNA polymerase binds the NTPs via covalent bonds. Two phosphate molecules are released to provide energy. The RNA strand is created in a 5'-3' direction until it reaches the terminator where both the RNA and polymerase detach.
DNA rewinds

Eukaryotic RNA:

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