DNA vs RNA Objective 10 0 Brief History

DNA vs. RNA Objective 10. 0

Brief History n n n The structure of DNA was not discovered until the early 1950’s. Rosalind Franklin used x-ray diffraction to study the shape of DNA. Watson, Crick, and Wilson were given the Nobel prize for identifying the structure of DNA.

Nucleic Acids n n Nucleic Acids contain the instructions needed to carryout life. There are two different types of nucleic acids, DNA and RNA. The subunits of nucleic acids are called nucleotides. Nucleotides are made up of a phosphate, nitrogen bases, and a sugar.

The Structure of DNA n n DNA is shaped like a double helix, or a twisted ladder. Nitrogen bases are paired together according to Chargaff’s rules. A=T G=C

Chargaff’s Rules n In DNA, Adenine is always paired with Thymine. Guanine is always paired with Cytosine.

DNA n n DNA provides the information to the cell for making all the proteins the cell needs. DNA has a specific code which is formed by a specific order of different nucleotides.

RNA n n RNA copies the DNA pattern of nucleotides and delivers the information to the ribosomes in the cytoplasm, during transcription. Transcription is the process in a cell by which genetic material is copied from a strand of DNA to a complementary RNA strand.

Translation n n Translation is the process by which a strand of messenger RNA directs the assembly of a sequence of amino acids to make a protein. Translation takes place in the ribosomes.

Transcription and Translation

DNA vs. RNA n n DNA is double stranded, stays inside the nucleus, and has thymine. RNA is single stranded, moves from the nucleus into the cytoplasm, and has uracil. Chargaff’s Rules A=U G=C

Mutations n n Mutations occur when there is a change in the order of bases in an organism’s DNA. Changes in the order of bases in DNA can occur in the order of bases in DNA: substitution, insertion, and deletion

Types of Mutations n Substitution- one nitrogen base is replaced by another ACTGTCAGG q Insertion- an extra nitrogen base is added to the base sequence ACTGTCAGG q ACTCTCAGG ACTGTTCAGG Deletion- one or more nitrogen bases are remove ACTGTCAGG ACTGTTCAG

Mutagens n n n Anything that causes a mutation is called a mutagen. Examples of mutagens are the Ultra Violet rays, x-rays, or other carcinogens. Mutations can be harmful, helpful, or make no difference at all.