are gene inside dna
The replication origin (ORI) is a specific DNA sequence of 50 – 100 base pairs that must be present in a plasmid for it to replicate. Host-cell enzymes bind to ORI, initiating replication of the circular plasmid. Each gene has a special job to do. The DNA in a gene spells out specific instructions—much like in a cookbook recipe — for making proteins (say: PRO-teens) in the cell. Proteins are the building blocks for everything in your body. Bones and teeth, hair and earlobes, muscles and blood, are all made up of proteins. General procedure for cloning a DNA fragment in a plasmid vector. Although not indicated by color, the plasmid contains a replication origin and ampicillin-resistance gene. Uptake of plasmids by E. coli cells is stimulated by high concentrations of CaCl (more...) Mouse olfactory cells contain the genes for 1,300 types of smell receptors, but only one of the genes turns on in each cell. In a 2006 paper researchers used fluorescent tags to show that a receptor gene becomes expressed only if it comes into physical contact with a specific part of chromosome 14. Chromosomes come in matching sets of two (or pairs) and there are hundreds — sometimes thousands — of genes in just one chromosome. The chromosomes and genes are made of DNA, which is short for deoxyribonucleic (say: dee-ox-see-ri-bo-nyoo-CLAY-ik) acid. Most cells have one nucleus (say: NOO-clee-us). In organisms called eukaryotes, DNA is found inside a special area of the cell called the nucleus. Because the cell is very small, and because organisms have many DNA molecules per cell, each DNA molecule must be tightly packaged. This packaged form of the DNA is called a chromosome. Positions of Genes Inside the Cell Nucleus Exert Biological Effects. For decades the cell nucleus has been a black box of biology—scientists have understood little about its structure or the way it operates. But thanks in part to new visualization technologies, biologists have recently begun probing the architecture of the nucleus in real time. Each DNA sequence that contains instructions to make a protein is known as a gene. The size of a gene may vary greatly, ranging from about 1,000 bases to 1 million bases in humans. Genes only make up about 1 percent of the DNA sequence. The phenomenon of transformation permits plasmid vectors to be introduced into and expressed by E. coli cells. In order to be useful in DNA cloning, however, a plasmid vector must contain a selectable gene, most commonly a drug-resistance gene encoding an enzyme that inactivates a specific antibiotic. Genes that are passed on to you determine many of your traits, such as your hair color and skin color. Maybe Emma's mother has one gene for brown hair and one for red hair, and she passed the red hair gene on to Emma. If her father has two genes for red hair, that could explain her red hair.
Yes, The DNA in a gene spells out specific instructions—much like in a cookbook recipe — for making proteins (say: PRO-teens) in the cell.