The Function of DNA

Organelles and Proteins The major functions of the cell are carried out in the organelles of the cell They are like the cell’s organs They process food, transport materials, help moves, etc. Organelles carry out these functions using proteins Organelles and Proteins

Proteins Proteins are molecules Proteins carry out all of the functions inside the cell They are a type of molecule called a polymer Polymer – made up of the same, repeating part. The repeating parts that make up a protein are called amino acids There are 20 amino acids in nature

Proteins Proteins are made of amino acids Amino Acids connect to each other making long chains The chain of amino acids is a protein

Proteins There are 20 amino acids The order they are connected is what determines the type of protein Each type of protein does a different job inside of the cell.

DNA Sequence The DNA sequence is the order the nitrogenous bases are attached DNA stores information by its sequence Much like a computer stores information in a sequence of 1’s and 0’s This sequence determines how the cell will function.

DNA Sequence This sequence is used to make proteins Proteins carry out all of the functions of the cell DNA makes proteins so this is how it controls the cell

Transcription DNA is first transcribed (rewritten) into RNA in the nucleus RNA is Ribonucleic Acid RNA is single stranded and looks like DNA It replaces Thymine (T) with Uracil (U) This process is called Transcription The type of RNA in this process is called mRNA mRNA is Messenger RNA

Transcription The mRNA leaves the nucleus and travels to the cytoplasm When in the cytoplasm it will go to the Ribosomes

Translation The ribosome attaches to the mRNA It then “reads” the mRNA in 3 letter sections called codons Each codon represents an amino acid Amino acids = building blocks of protein tRNA brings the correct amino acid to the ribosome

Translation The ribosome will then read the next 3 letter sequence (codon) This represents a new amino acid tRNA will bring this to the ribosome The ribosome will connect the amino acids together BOOM – protein! This process is called Translation

Genes Genes are sections of DNA that code for a single protein These are the sections that are transcribed (turned into mRNA) and then translated (read by ribosomes and made into proteins)

Genes to Proteins DNA makes genes Genes create proteins The types of proteins determine how the cell will function This is how DNA controls the function of the cell. DNA is a recipe for all of the proteins in the cell

Genetic Code The genetic code is the translation of DNA/RNA to Proteins. It shows us what codons are used for specific amino acids

Genes These genes are passed down when a living thing reproduces This means the offspring (children) will make the same proteins as the parents

Mutations Sometimes a cell will make a mistake and change a nucleotide in the DNA This change is called a mutation Mutations can be neutral, harmful, and rarely beneficial This depends on the change to the protein made

Cancer Cancer is typically caused by a mutation in the DNA This make the cell function so differently that it will only have the information to copy itself and reproduce This process happens more quickly and builds a large mass of improperly functioning cells

Viruses Viruses hijack the processes of transcription and translation to do their work Viruses are a protein that contains DNA or RNA Viruses find a way to get their DNA or RNA into a cell The cell reads it and makes the protein it codes for That protein, is a new virus! This process continues and releases viruses which then infect more cells

Genetic Engineering Genetic engineering is changing the genome (code) in a living thing. This is done by taking a section of DNA that codes for a protein you want. It is then put into a new cell’s DNA. The organism made from this cell will have this gene and make this protein.