* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download DNA
DNA sequencing wikipedia , lookup
Transcriptional regulation wikipedia , lookup
Genome evolution wikipedia , lookup
Silencer (genetics) wikipedia , lookup
Comparative genomic hybridization wikipedia , lookup
Promoter (genetics) wikipedia , lookup
Agarose gel electrophoresis wikipedia , lookup
Maurice Wilkins wikipedia , lookup
Community fingerprinting wikipedia , lookup
DNA vaccination wikipedia , lookup
Gel electrophoresis of nucleic acids wikipedia , lookup
Molecular evolution wikipedia , lookup
Transformation (genetics) wikipedia , lookup
Molecular cloning wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
Cre-Lox recombination wikipedia , lookup
Non-coding DNA wikipedia , lookup
DNA supercoil wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
DNA’s Function DNA • DNA deoxyribonucleic acid. http://ed.ted.com/lessons/ the-twisting-tale-of-dnajudith-hauck DNA • DNA carries the genetic information in the cell – the instructions for making all the structures and materials the body needs to function. DNA • DNA is capable of making a copy of itself through a process called, replication. Location of DNA • Most of the DNA occurs in the cell nucleus; however, each mitochondrion contains 37 genes – this is referred to as mitochondrial DNA. The structure of DNA • The shape of the molecule is described as a “double helix”. • The building blocks of DNA are nucleotides. The ladder model • The structure of DNA can be understood more easily by untwisting the double helix and displaying the molecule as if it were a ladder. The ladder model • The side rails of the ladder (the “backbone”) are alternating phosphate and sugar molecules. The rungs are paired nitrogen base molecules held together by a hydrogen bond. The base pairing rule • Each “rung” of the DNA ladder is formed from two nitrogen bases. The base pairing rule • There are four bases – adenine (A), thymine (T), cytosine (C), and guanine (G). • The base adenine always bonds with thymine (A-T), and cytosine always bonds with guanine (C-G). The base pairing rule • Chargaff’s Rule – The amount of adenine is the same as the amount of thymine, and the amount of cytosine is the amount of guanine. The structure of DNA • A nucleotide consists of one phosphate molecule, a fivesided sugar molecule (deoxyribose sugar), and one nitrogen base. The base pairs The binding of two nucleotides forms a base pair. In DNA, cytosine and guanine are bound together by 3 hydrogen bonds, whereas adenine and thymine are bound by 2 hydrogen bonds. NIH - National Human Genome Research Institute The function of DNA Genes • A chromosome consists of segments of DNA known as genes. The function of DNA Genes • Genes contain the instructions for the construction of a particular protein, or RNA. The genetic code • The sequence of bases in a gene is a code instructing the cell how to construct a particular protein. The genetic code • Proteins are responsible for different functions throughout the body. – Hormones, hemoglobin, insulin, etc. • Proteins are involved in the expression of traits. – Curly hair, eye color, skin tone, etc. The function of DNA Genes • It is estimated that there are about 20,000– 25,000 genes in the human genome (i.e. about 3 billion base pairs). Introns and exons • Genes consist of introns and exons • Exons are sections of coding DNA – i.e. they contain instructions for making proteins. • Introns are sections of non-coding DNA (once called "junk DNA") – i.e. they do not contain instructions for making proteins but are now believed to serve other important functions. DNA Packaging • DNA is very thin and very fragile. • Around 6 feet of DNA must fit inside each cell’s nucleus. • How is this possible? DNA Packaging • First: DNA is wrapped around proteins called Histones, this new structure is called a Nucleosome. DNA Packaging • Second: The Nucleosomes tighten up and form loops. DNA Packaging • Third: The loops tighten together to form supercoils, known as chromatin. DNA Packaging • Finally: the chromatin condenses, during prophase, to form chromosomes. DNA Packaging Fight or Flight response in the body • http://learn.genetics.utah.edu/content/be gin/cells/cellcom/