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Protien Molecules Research Paper

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The production of protien molecules happends in two stages, transcription and translation. Transciption takes place in the nucleus. First, DNA in the nucleus,its double stranded in eukaryote cells. DNA molecule unfolds forming two templates of DNA. RNA polymerase attaches itself to a template of DNA and synthesizes mRNA. DNA contains the cistrons/genes which code for specific polypeptides. The part of the strand that forms the cistron is called the transcribing strand. It acts as a template and is transcribed to mRNA. The complementary strand which does not carry the cistron is called the non-transcribing strand. An enzyme RNA polymerase attaches itself to the promoter site next to the cistron on the DNA and initiates transcription. The enzymes …show more content…

Base pairing occurs.Translation is the process in which the codons in mRNA are used to assemble amino acids in the correct sequence to produce a polypeptide chain. mRNA binds to the binding site on the smaller ribosomal subunit. tRNA carries amino acid to the ribosome. Cells posses more than 20 types of tRNA, more than enough for the different amino acids. The codon of mRNA forms hydrogen bonds with the anticodon of tRNA. The tRNA detaches itself from mRNA and returns to the cytoplasm to take up more amino acids. Once aligned, peptide bonds are formed between adjacent amino acids, eventually forming a polypeptide chain. rRNA consists of a single polynucleotide strand synthesised in the nucleus. The rRNA form aggregates which proteins to form the large subunit and small subunit. The subunits leave the nucleus via nuclear pore into the cytoplasm. The subunits combine to form a ribosome. rRNA means ribosomal RNA, mRNA means messenger RNA, tRNA means Transfer RNA, rRNA means Ribosomal RNA. Ribosomal molecules of mRNA determine the order of tRNA molecules that are bound to triplets of amino acids …show more content…

During the process of transcription, an enzyme called RNA polymerase binds to DNA at a gene's promoter, then begins unwinding the DNA and making a complementary strand of RNA from the exposed DNA template. Depending on the gene being transcribed, the result can be a molecule of mRNA (messenger RNA), tRNA (transfer RNA), or rRNA (ribosomal RNA). Each type of RNA performs a specific function later in translation. Ribosomal RNA (rRNA) along with ribosomal proteins make up ribosomes, the "workbenches" on which polypeptides (proteins) are synthesized. It turns out that it is actually rRNA, and not a protein, in the large subunit of the ribosome that performs the peptidyl transferase function of linking amino acids together via peptide bonds. In eukaryotes, the genes coding for rRNAs are located in the nucleolus of the nucleus. A ribosome has 3 binding sites: an A (aminoacyl) site, a P (peptidyl) site, and an E (exit) site. The message carrying the information needed to make a particular polypeptide exists in the mRNA molecule. It binds with a ribosome and the ribosome starts reading it one codon - 3 consecutive mRNA bases - at a

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