lab 7

language of proteins consists of

20 amino acids.

the language of nucleic acids involves

4 bases in DNA and RNA

Since proteins are the functional workhorse of the cell,

DNA serves as the genetic blueprint for an organism by providing the blueprint to build all of its proteins, and therefore determining what functions a cell is carrying out at any given time.

DNA represents the permanent blueprint of information that a cell/organism has to define everything it can do

It is the defining molecule of an organism, in that it differentiates one species from another, as well as makes an individual unique, as well as determining what a cell/organisms capabilities are. It does so by coding the information necessary to build all of the proteins that a cell/organism may ever need.

These same base pairing rules allow one strand of DNA to serve as a template to build

RNA as well, with some small differences.

The flow of information within a cell moves from DNA to RNA to proteins.

This idea is called the Central Dogma of (Molecular) Biology because all living organisms work this same way.

Each codon correlates to a specific

an amino acid, except for three that have no amino acid correlation, and are therefore stop codons. A codon must be three letters in length because this is the minimum code that will include enough combinations to cover all 20 amino acids. However, having this three letter code also means that there is a lot of redundancy in the genetic code, and so there are often multiple codons corresponding to one amino acid.

The process of transcription is based on the fundamental structure of DNA, which allows for easy

copying.

DNA is a

double helix of anti‐parallel strands held together by hydrogen bonds between base pairs.

The bases of DNA are

e adenine (A), cytosine (C), guanine (G), and thymie (T), and these represent the letters of the DNA language/code.

protein is the

functional molecule that carries out almost all active processes within a cell.

RNA is transcribed only from a

gene segment, not the entirety of the DNA.

For translation to work, therefore, there must a

genetic code that can be used to translate nitrogenous bases into amino acids. This genetic code works on a three‐letter code, called a codon.

DNA contains the permanent blueprint for all of a cell's proteins; known as the

genome.

Second, RNA

is a single strand, and is therefore only transcribed from one of the DNA strands.

The process of translation, on the other hand, involves turning the language of nucleic acids into the

language of proteins.

process of gene expression represents the

movement of information from DNA RNA proteins.

Protein function is defined by the

overall three dimensional structure of the protein, as this determines what other molecules a protein can interact with. The 3D structure of a protein (i.e. it's 4° structure) is determined by the primary (1°) structure of the protein, which is the sequence of amino acids that make up the protein. For a given protein, this might be hundreds to thousands of amino acids, which then fold over onto each other based on backbone and R‐group interactions to give rise to the overall structure. So, in order for nucleic acids to give rise to protein structure, the 4 bases in DNA and RNA must be able to code for the sequence of amino acids that create a protein.

Translation works by having a large enzyme complex, the

ribosome, able to read a piece of RNA one codon at a time, and plug in the appropriate amino acid into the growing peptide chain. In this way, the sequence of a gene in DNA determines the function of a protein. Because the genetic code is based on a triplet codon, it is very important that the ribosome read the RNA in the correct reading frame, so that the correct amino acid sequence is produced.

gene is a

short segment within the genome that represents the blueprint for one protein/polypeptide;

Base pairing rules allows one strand to serve as a

template to build the opposite strand of DNA.

RNA is a

temporary of the code contained by the gene.

The two steps in this process are

transcription, the process of making RNA from DNA, and translation, the process of turning RNA into a protein.

third, DNA uses

uracil (U) in place of T. The process of transcription then involves one enzyme, RNA polymerase, unzipping the DNA, using base pair rules to plug in complementary bases to the template strand of a gene, and then closing up the DNA again.