Genetics Concept Map by Monique Wiggins on Prezi
Source: National Human Genome Research Institute and the Smithsonian Description: Interactive tutorials on DNA, genes, chromosomes, protein, heredity, and traits . Description: Students breed dragons to learn concepts of modern genetics Experiment with the forces involved and measure the relationship between. be able to: Draw a diagram, create a concept map, or write a paragraph that explains the relationships among these terms: variations in the structure of the DNA molecule of a gene for a particular trait;. the existence of The Relationship Between Genes, Proteins, and Traits. A gene CFTR genomic DNA sequence. The term 'gene' refers to a stretch of DNA that codes for a protein. The vast majority (98%) of the human genome does not encode functional proteins, and is .
First, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.
Others genes have "weak" promoters that form weak associations with transcription factors and initiate transcription less frequently. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence and bound transcription factor become close to the RNA polymerase binding site.
The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product. The term cistron in this context is equivalent to gene. The products of operon genes typically have related functions and are involved in the same regulatory network. Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.
This concept originally called the one gene-one enzyme hypothesis emerged from an influential paper by George Beadle and Edward Tatum on experiments with mutants of the fungus Neurospora crassa. In actuality they proved to be the opening gun in what became molecular genetics and all the developments that have followed from that.
Gene expression In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. Genetic code[ edit ] Schematic of a single-stranded RNA molecule illustrating a series of three-base codons. Each three- nucleotide codon corresponds to an amino acid when translated to protein The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code.
Sets of three nucleotides, known as codonseach correspond to a specific amino acid. Additionally, a " start codon ", and three " stop codons " indicate the beginning and end of the protein coding region.
- DNA, genes and chromosomes
- DNA, Genes and Chromosomes
The correspondence between codons and amino acids is nearly universal among all known living organisms. They contain the information our bodies need to make chemicals called proteins.
Proteins form the structure of our bodies, as well playing an important role in the processes that keep us alive. Genes are made of a chemical called DNA, which is short for 'deoxyribonucleic acid'.
DNA, genes and chromosomes — University of Leicester
The DNA molecule is a double helix: The DNA double helix showing base pairs The sides are sugar and phosphate molecules. The rungs are pairs of chemicals called 'nitrogenous bases', or 'bases' for short. There are four types of base: These bases link in a very specific way: A always pairs with T, and C always pairs with G.
The DNA molecule has two important properties. It can make copies of itself. If you pull the two strands apart, each can be used to make the other one and a new DNA molecule. The process is catalysed by the enzyme DNA polymerase, and includes a proofreading mechanism. Genes The gene is the basic physical and functional unit of heredity. It consists of a specific sequence of nucleotides at a given position on a given chromosome that codes for a specific protein or, in some cases, an RNA molecule.
Genes consist of three types of nucleotide sequence: These genes are known, collectively, as the human genome.
Chromosomes Eukaryotic chromosomes The label eukaryote is taken from the Greek for 'true nucleus', and eukaryotes all organisms except viruses, Eubacteria and Archaea are defined by the possession of a nucleus and other membrane-bound cell organelles.
The nucleus of each cell in our bodies contains approximately 1. This DNA is tightly packed into structures called chromosomes, which consist of long chains of DNA and associated proteins.
Intro to gene expression (central dogma)
In eukaryotes, DNA molecules are tightly wound around proteins - called histone proteins - which provide structural support and play a role in controlling the activities of the genes. A strand to nucleotides long is wrapped twice around a core of eight histone proteins to form a structure called a nucleosome. The chains of histones are coiled in turn to form a solenoid, which is stabilised by the histone H1.
Further coiling of the solenoids forms the structure of the chromosome proper.
Each chromosome has a p arm and a q arm. The p arm from the French word 'petit', meaning small is the short arm, and the q arm the next letter in the alphabet is the long arm.
In their replicated form, each chromosome consists of two chromatids.