protein synthesis translation and transcription

• Protein synthesis involves two main steps: transcription and translation
• Transcription is the process of copying a single gene of DNA into mRNA
• Translation is the process of using mRNA to produce a protein
• DNA contains thousands of genes, each coding for a specific sequence of amino acids to form a protein
• Ribosomes, which read the DNA bases to make proteins, are located outside the nucleus
• Messenger RNA (mRNA) is a copy of a single gene, shorter than DNA, single-stranded, and contains uracil instead of thymine
• During transcription, RNA polymerase binds to DNA, separates the two strands, and reads the bases to create an mRNA strand
• The mRNA bases are complementary to the DNA bases, with uracil pairing with adenine instead of thymine
• The DNA strand keeps separating and closing as the RNA polymerase moves along, exposing only a small section at a time
• The template strand of DNA is used to make the mRNA during transcription
• After transcription, the mRNA leaves the nucleus and heads to the ribosome for translation
• Each group of three bases on DNA or mRNA (codon) codes for a specific amino acid
• Cells use 20 different amino acids, each with a unique three-base codon
• Transfer RNA (tRNA) molecules bring amino acids to the ribosome based on the complementary anticodon to the mRNA codon
• tRNA ensures the correct amino acids are brought in the correct order for protein synthesis
• Ribosomes join amino acids brought by tRNA to build a chain of amino acids, forming a protein
• The process repeats along the mRNA until a complete chain of amino acids is formed and the protein is released