Protein Synthesis

368 Words1 Page
bulb-icon

Recommended: Quizlet protein synthesis ap bio

Protein Synthesis

Within the nuclei of every one of our cells lie massive amounts of information. This information is stored neatly in our chromosomes. The coding on these chromosomes dictates every aspect of our physical self, but it is useless if it simply remains undecoded in the depths of our nuclei; it must be translated into something that can be read. This happens in the process of protein synthesis.

The first part of the process of protein synthesis is transcription - the creation of RNA based on the DNA template. First the enzyme RNA polymerase helps to unwind the DNA helix. Then the DNA is elongated. RNA polymerase binds to one strand of the DNA at the promoter sequence (a specific sequence of nucleotides on the DNA chain) and when it reaches the start signal, the formation of mRNA begins. Transcription stops when it reaches the termination signal.

After the RNA strand is formed, there are several intervening steps to prepare the mRNA for translation. First, the strand is “tagged” on both 3’ and 5’ ends to designate the strand as mRNA. Next, sections of the strand - called introns - are removed with the help of snRNPs (pronounced “snirp”) and the strand is spliced back together. Once this has occurred, the remaining part, the extron is expelled into the cytosol (the cellular fluid surrounding the nucleus and all other organelles) through pores in the nuclear membrane.

Once in the cytosol, the mRNA must find a ribosome (a small organelle in the cytosol) onto which it may bind during translation - the process of decoding the RNA to form a polypeptide (protein) chain. First, it binds to the small ribosomal subunit, which, in turn, binds to the large subunit. Then there is a short spurt of translation which stops almost immediately in order for the entire complex of mRNA and Ribosome to move to the rough Endoplasmic Reticulum (another organelle, usually abbreviated ER). At the ER, translation resumes and the resulting amino acid chain (protein) goes into the lumen (inner chamber) of the ER for packaging, sorting, etc.

The actual formation of the polypeptide chain occurs only with the assistance of tRNA which brings single amino acids to the mRNA, beginning with methionine (coded AUG). The first tRNA binds at the P-site, but when the A site is occupied by the subsequent tRNA molecule, the original amino acid moves over to the second tRNA.

Show More
Related

  • Lab: Enzymes – Protein Catalysts

    870 Words  | 2 Pages

    Abstract: Enzymes are catalysts therefore we can state that they work to start a reaction or speed it up. The chemical transformed due to the enzyme (catalase) is known as the substrate. In this lab the chemical used was hydrogen peroxide because it can be broken down by catalase. The substrate in this lab would be hydrogen peroxide and the enzymes used will be catalase which is found in both potatoes and liver. This substrate will fill the active sites on the enzyme and the reaction will vary based on the concentration of both and the different factors in the experiment. Students placed either liver or potatoes in test tubes with the substrate and observed them at different temperatures as well as with different concentrations of the substrate. Upon reviewing observations, it can be concluded that liver contains the greater amount of catalase as its rates of reaction were greater than that of the potato.

    Read More

  • Unit 18: Genetics And Genetic Engineering

    762 Words  | 2 Pages

    In order to do this a polymer of DNA “unzips” into its two strands, a coding strand (left strand) and a template strand (right strand). Nucleotides of a molecule known as mRNA (messenger RNA) then temporarily bonds to the template strand and join together in the same way as nucleotides of DNA. Messenger RNA has a similar structure to that of DNA only it is single stranded. Like DNA, mRNA is made up of nucleotides again consisting of a phosphate, a sugar, and an organic nitrogenous base. However, unlike in DNA, the sugar in a nucleotide of mRNA is different (Ribose) and the nitrogenous base Thymine is replaced by a new base found in RNA known as Uracil (U)3b and like Thymine can only bond to its complimentary base Adenine. As a result of how it bonds to the DNA’s template strand, the mRNA strand formed is almost identical to the coding strand of DNA apart from these

    Read More

  • Enzyme Peroxidase Lab Report

    808 Words  | 2 Pages

    This is made possible by the use of enzymes. Enzymes essentially work within the cells and their ability determined as a result of their specificity brought about by the shapes from the amino acid sequences (Daniel and Danson 2740).

    Read More

  • Overview Of The Endocrine System

    1577 Words  | 4 Pages

    ... the codon for the amino acid methionine is added the head of each chain.

    Read More

  • The Pros And Cons Of Transcription Factors

    1265 Words  | 3 Pages

    In bacteria, RNA polymerase attaches right to the DNA of the promoter. You can see how this process works, and how it can be regulated by transcription factors, in the lac operon and trp operon videos.

    Read More

  • Causes Of Pancreatic Cancer

    756 Words  | 2 Pages

    ... have been doing a phenomenal job of figuring this out. DNA is the chemical in each cell that carries our genes. DNA is the source of just about everything. It not only determines what we look like, but also many other things. Instructions are on some of our genes to let them know when they need to multiply and divide. Cancers can be caused by DNA defects.

    Read More

  • Nature vs. Nurture - We are Influenced by a Combination

    1328 Words  | 3 Pages

    “A gene is a segment of DNA or a sequence of nucleotides in DNA that code for a functional product,” Tortora. Microbiology. p. 575. The syllable of the syllable. These genes not only affect our outlook, but also play a role.

    Read More

  • The Functions of Proteins

    923 Words  | 2 Pages

    The Functions of Proteins Introduction Protein accounts for about three-fourths of the dry matter in humans. tissues other than fat and bone. It is a major structural component of hair, skin, nails, connective tissues, and body organs. It is required for practically every essential function in the body. Proteins are made from the following elements: carbon, hydrogen, oxygen, nitrogen. and often sulphur and phosphorus.

    Read More

  • Nucleus Essay

    468 Words  | 1 Pages

    The nucleus is the place for DNA transcription in which messenger RNA (mRNA) that synthesizes protein, is produced. The nucleus contains numerous types of proteins which can either directly control transcription or are indirectly involved in regulating the process. The process of energy and nutrient metabolism in the cell is regulated by the nucleus. It directs the synthesis and functioning of enzymes; a type of protein.

    Read More

  • Gene Expression in Eukaryotes

    933 Words  | 2 Pages

    The amount of information encoded by the genes within a cell is enormous, although some will never be expressed while others occasionally during its life cycle. For example some genes that encode for ribosomal RNA are being expressed continuously because they are responsible with the formation of proteins in the cell’s cytoplasm. Specific RNA molecules and proteins are expressed in all cells at all times, their genes going under the name of housekeeping genes. They are responsible with the maintenance of the cells and can aid geneticists recognize their function (Brown, 2011).

    Read More

  • Protein Synthesis

    787 Words  | 2 Pages

    Protein synthesis is one of the most fundamental biological processes. To start off, a protein is made in a ribosome. There are many cellular mechanisms involved with protein synthesis. Before the process of protein synthesis can be described, a person must know what proteins are made out of. There are four basic levels of protein organization. The first is primary structure, followed by secondary structure, then tertiary structure, and the last level is quaternary structure. Once someone understands the makeup of a protein, they can then begin to learn how elements can combine and go from genes to protein. There are two main processes that occur during protein synthesis, or peptide formation. One is transcription and the other is translation. Although these biological processes slightly differ for eukaryotes and prokaryotes, they are the basic mechanisms for which proteins are formed in all living organisms.

    Read More

  • Essay On Proteins

    1463 Words  | 3 Pages

    A polypeptide chain is a series of amino acids that are joined by the peptide bonds. Each amino acid in a polypeptide chain is called a residue. It also has polarity because its ends are different. The backbone or main chain is the part of the polypeptide chain that is made up of a regularly repeating part and is rich with the potential for hydrogen-bonding. There is also a variable part, which comprises the distinct side chain. Each residue of the chain has a carbonyl group, which is good hydrogen-bond acceptor, and an NH group, which is a good hydrogen-bond donor. The groups interact with the functional groups of the side chains and each other to stabilize structures. Proteins are polypeptide chains that have 500 to 2,000 amino acid residues. Oligopeptides, or peptides, are made up of small numbers of amino acids. Each protein has a precisely defined, unique amino acid sequence, referred to as its primary structure. The amino acid sequences of proteins are determined by the nucleotide sequences of genes because nucleotides in DNA specify a complimentary sequence in RNA, which specifies the amino acid sequence. Amino acid sequences determine the 3D structures of proteins. An alteration in the amino acid sequence can produce disease and abnormal function. All of the different ways

    Read More

  • The Importance Of Protein Nutrition

    1374 Words  | 3 Pages

    Moderation is vital in all aspects of life and is necessary for overall health, including with one’s food intake. Protein is one of the many important nutrient building blocks that is necessary for proper growth and good health. However, eating excessive amounts of any nutrient or inadequate amounts, can cause various health concerns. Scientists have been able to estimate the amount of nutrients that the body requires. However, the amount of any particular nutrient varies from person to person, depending on your “age, sex, general health status, physical activity level, and use of medications and drugs” (Schiff 2013). It is also important to remember that consuming the required amount of nutrients that meets your dietary guidelines does not

    Read More

  • Cell Cycle Essay

    1327 Words  | 3 Pages

    During this phase the DNA aka “deoxyribose nucleic acid” clone then forms chromatin. Chromatin is the mass of genetic material that forms into chromosomes. Interphase is divided into smaller parts: G1 Phase, S phase and G2 Phase. Throughout all the phases, the cells continuously develop by producing mitochondria, endoplasmic reticulum, and proteins. The actual division occurs during the S phase bur the G phases are mainly for the purpose of growing. Starting with the G1 phase the cell grows in preparation for certain intracellular components and DNA replication. This phase makes sure the cell is prepared for the process of DNA replication. It reviews the size and environment to ensure that is it ready to go, and cannot leave the G1 until it is complete. But what happens to a cell when it is not complete and cannot exit out of the phase? It will pause and transfer to phase G0. There’s no certain time to be in this phase but it will remain until it reaches the fitting size and is in a supportive surroundings for DNA replication. It will exit either G1 or G0 and there is no other way besides these. Then the cell will advance to the next phase which is the S phase. Synthesis, or more known as S phase is the section of the cell cycle when the DNA is wrapped into chromosomes then duplicated. This is a very important part of the cycle because it grants each of them that is created, to have the exact same genetic

    Read More

  • The Transgenic Tomato

    2482 Words  | 5 Pages

    ...ill form a string, and the tRNA molecules will be released into the cell. When this string of amino acids is completed, it is called a protein. Some proteins provide structure in living things (such as the protein in muscle tissue), while others can promote certain chemical reactions in cells (such as the breakdown of pectin in tomato cell walls).

    Read More

More about Protein Synthesis

Open Document