The Genetic Code and Protein Synthesis
Genetic code is the sequence of organic bases on the double strands of
DNA. These bases line up in a particular order to code for things like
eye colour, hair colour and height. Every person has an individual
genetic code and no two persons are exactly the same.
DNA replicates in a semi-conservative manner. The two strands are
separated by an enzyme called Helicase and both become templates for
new DNA. Each strand then attracts new organic bases to the ones
already present e.g. If the code on one strand was TGACACCCTGGTAGCAGT,
then the attracted organic bases would be ACTGTGGGACCATCGTCA. Another
enzyme called DNA Polymerase holds the amino acids in place, while the
sugar-phosphate back-bone is formed. One final enzyme- ligase- fixes
any broken bits of the DNA together.
Messenger RNA is made in a very similar way to DNA, except Thymine is
replaced by Uracil. Messenger RNA is also formed from a template
strand of DNA. This process is known as transcription. Helicase
unwinds the double strand, then organic bases line up next to the
corresponding bases on the DNA. It then peels away from the DNA and
exits through pores in the nuclear envelope into the cytoplasm. Once
in the cytoplasm it attaches to a ribosome, which causes amino acids
to assemble in the right order. The DNA then winds back up into its
original shape.
Transfer RNA helps the amino acids to assemble along the strand. They
also transfer amino acids to the ribosome. Amino acids attach to one
end of the tRNA and the tRNA binds to the mRNA. Cells posses over 20
types of tRNA which are all that is needed. The tRNA lines up with
corresponding bases on the mRNA, which is called a codon. The end on
the tRNA is called an anticodon.
Miller, Kenneth R. and Joseph S. Levine. “Chapter 12: DNA and RNA.” Biology. Upper Saddle River: Pearson Education, Inc., 2002. Print.
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
In the most general terms, the nucleus is the command center of a eukaryotic cell. Although the origin of the organelle is unclear, it is believed that it is derived from a symbiosis relationship between a bacterium and an archaea (Martin W. 2005). Being the main hub for the inner workings of a cell involves different functions overall. These nucleic functions are determined by the genes within the DNA of the cell. Functions of the cell are also regulate by soluble proteins that come in and out of the cell via the membranes and specific channels or the nuclear pore complexes. The overall objectives of the nucleus include; gene expression, compartmentalization, and processing pre-mRNA. The functions of the organelles and sub-regions
The study of nucleic acids has now become a fruitful and dynamic scientific enterprise. Nucleic acids are of unique importance in biological systems. Genes are made up of deoxyribonucleic acid or DNA, and each gene is a linear segment, or polymer, of a long DNA molecule. A DNA polymer, or DNA oligonucleotide, contains a linear arrangement of subunits called nucleotides. There are four types of nucleotides. Each nucleotide has three components; a phosphate group, a sugar and a base that contains nitrogen within its structure. The sugar moiety in DNA oligonucleotides is always dexoyribose, and there are four alternative bases: adenine (A), thymine (T), guanine (G), and cytosine (C). The phosphate groups and the deoxyribose sugars form the backbone of each DNA stand. The bases are joined to the deoxyribose sugar and stick out to the side. Both oligomers, DNA and RNA, consist of 5’->3’ phosphodiester-linked nucleotide units that are composed of a 2’-deoxy-D-ribose (DNA) or D-ribose (RNA) in their furanose forms and a heteroaromatic nucleobase (A, T, G, and C; A, U, G, C), and the resulting oligonucleotide chain is composed of a polar, negatively charged sugar-phosphate backbone and an array of hydrophobic nucleobases. The amphiphilic nature of these polymers dictates the assembly and maintenance of secondary and tertiary structures the oligonucleotides can form. In the DNA duplex structure, genetic information is stored as a linear nucleotide code. This code can be accessed and replicated. RNA, or ribonucleic acid, is another structurally related essential biopolymer. RNA differs from DNA in having the sugar ribose in place of the deoxyribos...
This encyclopedia was extremely helpful. In not knowing all of the exact terms and basic knowledge of genetic engineering, it helped inform any reader of all this and more. The pages that had information on genetics and genetic engineering, had detailed definitions and descriptions for all the terms and ideas. Instead of focusing more towards the future of genetic engineering, it gave numerous facts about the technology and accomplishments of today. In addition to basic knowledge information, history, diagrams, and background information was provided. Including genetic testing, genes and their formation, and genetic background. The encyclopedia gave easy, organized, and accessible information to use.
Imagine having to explain to your child why they don’t look like you because of you’re selfishness. Imagine thinking your going to design your baby and turns out it has severe leukemia because scientists didn’t put together your baby right. Where Genetic Engineering and Cloning is headed this is possible. Not only is this effecting your child its affecting the whole world as well. Many people think they only do this in humans it happens in plants and animals too. Genetic Engineering and Cloning changes the natural possess in humans, plants, and animals.
There is no surprise that food is important in all aspects of our lives—it is shared amongst families, celebrated as a major part of our culture, and crucial to our daily routine that keeps us fit, healthy, and active. Today’s western culture glorifies a skewed perspective on how food is supposed to fit into our lives. Somehow this perception has led us to believe we no longer have the time or money it takes to prepare a wholesome, healthy meal that is shared at the dinner table with family. Instead, we are trained to want a meal that is fast, cheap, and easy. This meal is usually highly processed and filled with sugars and fats. This has led us to a problem of epidemic proportions characterized by the rapid increase in obesity and diabetes.
mRNA binds to the binding site located on the small subunit of the ribosome, which is part of the ribosomal RNA. tRNA then binds to the start codon. tRNA binds to one of the tRNA-binding sites on the large subunit after the large and small subunit bind together to create a ribosome. The tRNA binding site is called the P site, this is where the growing polypeptide will be. The open tRNA is called the A site and it is ready for a new tRNA to be bound.
For numerous years, the world’s most prestigious geneticists have been trying to crack the human genetic code, the intricate puzzle that defines each and every one of us as individuals. With the monumental success of the Human Genome Project, a new and exciting biological frontier is ready for exploration. The ramifications of the knowledge derived from this endeavor will no doubt be staggering for residents of the Rio Grande Valley and the world at large.
Contain a single-stranded, non-segmented RNA genome and four structural proteins
Distinct characteristics are not only an end result of the DNA sequence but also of the cell’s internal system of expression orchestrated by different proteins and RNAs present at a given time. DNA encodes for many possible characteristics, but different types of RNA aided by specialized proteins sometimes with external signals express the needed genes. Control of gene expression is of vital importance for an eukaryote’s survival such as the ability of switching genes on/off in accordance with the changes in the environment (Campbell and Reece, 2008). Of a cell’s entire genome, only 15% will be expressed, and in multicellular organisms the genes active will vary according to their specialization. (Fletcher, Ivor & Winter, 2007).
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.
The information form DNA is used as a template and rewritten onto RNA resulting in the molecule messenger RNA (mRNA) which carries a genetic message from DNA to the protein synthesizing part of the cell. Translation is the synthesis of a polypeptide using information provided by mRNA. In the ribosomes, the cell translates the nucleotide sequence of mRNA molecule into the amino acid sequence of a polypeptide. Transcription and translation occur in both prokaryotes and eukaryotes. In eukaryotes, the nuclear membrane separates transcription and translation, while in prokaryotes, there is no membrane so mRNA may begin transcription before translation is complete. Eukaryotic RNA transcripts are modified through RNA processing to yield finished
What scientists mean when they say that all living organisms share a universal genetic code, is that a percentage of DNA in all organisms is the same. Since all organisms share a amount of the same DNA, that means they are all related, and share a universal genetic code. A universal genetic code relates to the hypothesis about the origin of life on Earth, because even though organisms can look totally different, they have to all come from the same origin to share similar genetic codes. Self-replicating molecules are essential to the most popular hypothesis about the origin of life on Earth because of self replicating molecules explain how one organism could have a similar genetic code, as another organism. For example a human and a look completely