Presentation on theme: "From Gene to Protein. DNA Review n Is made of nucleotides. n Contains deoxyribose sugar n Thymine, Guanine, Cytosine, Adenine n Is a double stranded molecule."— Presentation transcript:
Explain: n Amino Acids – the building blocks of proteins. n Many amino acids linked together make up the many different proteins in our body. n DNA contains the code for these proteins and RNA’s assemble the parts.
Protein Synthesis: overview n Transcription: synthesis of RNA under the direction of DNA (mRNA) n Translation: actual synthesis of a polypeptide under the direction of mRNA
RNA Getting Ready to Do its Job n There is NOT just one RNA molecule!!!! THERE ARE THREE!!! n 3 types of RNA molecules: 1. Messenger RNA (m-RNA) 2. Transfer RNA (t-RNA) 3. Ribosomal RNA (r-RNA) n Each RNA molecule has a specific job in making a protein
m-RNA (Transcribes the DNA) n Messenger RNA copies the code for a protein from DNA. n This is called TRANSCRIPTION (Only Occurs INSIDE of the Nucleus of a Cell) n Takes code to the ribosome where the protein will be made. n m-RNA is divided into smaller units called CODONS.
What is a Codon? n Codon - series of 3-nucleotide ‘words’ found on the mRNA for ONE amino acid n The genetic instructions are ‘written’ in the DNA as a triplet code
Translation NOW Occurs n Translation –Interpretation or Decoding of the protein code from DNA n Occurs in the cytoplasm of the cell n NOT THE NUCLEUS n Involves mRNA, as well as, tRNA and rRNA
t-RNA, Slide 1 (Transfer RNA) n Carries the specific amino acid to the ribosome. n Each t-RNA will hook up with a codon. n One or more t-RNA for each amino acid. n Attach to the codon and have an area called an ANTI-CODON.
tRNA, Slide 2 n The three letter code on the tRNA is called an Anticodon n This code translates what amino acid should be made
Translation Summary n mRNA from nucleus is ‘read’ along its codons by tRNA’s anticodons at the ribosome in the cytoplasm n tRNA anticodon (nucleotide triplet); brings ONE amino acid
Ribosomes and rRNA (ribosomal RNA) n Ribosomes –Protein factories –Only Non-membrane bound organelle n rRNA –What makes up the ribosomes of the cell. –Found in high concentration in the nucleolus of the cell’s nucleus.