I am in ninth grade Biology. 1. The problem statement, all variables and given/known data I have some essay prompts given to the class by my biology teacher ahead of time before the finals. She will pick on of the prompts randomly on the day of the finals and so I must be familiar with all of them. I realize it is unscrupulous of me to try and cram information on the night before the final. I have most of this essay covered, except for one little part. In the Golgi Apparatus, the protein is modified and sort, and then it gets packaged in a vesicle to be shipped off to its final destination throughout the cell. So how does a protein "get inside" a lysosome? Come to think of it, are lysosomes formed from digestive enzymes, or do the digestive enzymes enter the lysosome? What happens when a lysosome doesn't function properly anymore? 2. Relevant equations This is the whole prompt if you want to read it: Trace the path of an amino acid during the production of a protein from the DNA in the nucleus to its incorporation as a digestive enzyme in a lysosome. Include the function of the digestive enzymes in a lysosome in your answer. 3. The attempt at a solution This would be my essay. You can skim the stuff in italics. Even if you catch stuff that isn't detailed or explained properly, that's okay, because I'm not turning this in ... just trying to memorize its contents: The process of the production of a protein is called The Central Dogma. This begins with the DNA in the nucleus of the cell. The first step, transcription, is making RNA from DNA. First, RNA polymerase unwinding DNA. One strand of the DNA will be used as a template from which free nucleotides assemble into a strand of messenger RNA, because RNA is single-stranded, unlike DNA. RNA has the nitrogenous uracil instead of thymine, so its base pairings are A=U, T=A, G=C, and C=G. On the mRNA molecule are many specific sequences of three nucleotides called codons. After mRNA has been copied from the DNA's gene sequence, the mRNA carryin the instructions for assembling a protein leaves the nucleus through the nuclear membrane and into the rough endoplasmic reticulum of the cytoplasm. This ER is called the rough ER because of the ribosomes on its surface. The next step, translation (also known as protein synthesis), involves mRNA binding to a ribosome, where the message is translated into a sequence of amino acids. Transfer RNA, or tRNA carry the amino acids that make up a protein. On one end of the tRNA molecule is its specific amino acid, and on the other end of the tRNA is a specific sequence of three nucelotides, called an anticodon. Only the information contained up to the stop codon in the mRNA molecule is used to produce the amino acid sequence. Starting with the start codon (AUG), the ribosome reads sets of three nucleotides at a time until a stop codon is reached. As the ribosome reads the nucleotides, the amino acids on the other end of the tRNA bind to each other with peptide bonds. When they bind, the tRNA is removed from the amino acid and ribosome for a new tRNA to take its place. The amino acid on that tRNA will attach the growing amino acid with peptide bonds and so on until the stop codon. Then the new protein, ribosome, and mRNA will separate. The newly made protein is then go into the rough ER, where it may be chemically modified. Proteins that are released, or exported, from the cell are synthesized on the rough ER. Proteins produced in the rough ER move next into an organelle called the Golgi apparatus. The golgi apparatus modifies, sorts, and packages proteins from the ER. From the Golgi apparatus, proteins are then shipped to their final destinations throughout the cell or outside of the cell in a membrane package called a vesicle. [here is where it gets awkward] Lysosomes have many enzymes which are synthesized on the rough ER, travel to and are sorted in the Golgi apparatus. The digestive enzymes of the lysosome break down macromolecules that come in the cell and remove old nonfunctioning organelles. - I'm not going to turn this essay in, because I copied a lot of things word for word from my textbook and the internet. I'm just going to try and memorize this information.