Biology: Dna and Gene Expression Essay

Submitted By shasta86
Words: 562
Pages: 3

In ________ organisms, the primary function of a gene is to participate in regulating the body as a whole and not to responding to the cell’s immediate environment. | mulitcellular | The maintenance of a constant environment in a cell is called | Homeostasis | A bacterial cell takes advantage of changing _______ conditions through control of gene expression. | Environmental | The most common form of regulation in bacteria and eukaryotes is | Transcriptional control | All regulatory proteins have common DNA binding motifs, which are particular bends in their protein chains that permit them to interlock with the | Major groove of the DNA helix | Regulatory proteins shut off transcription by binding to a site immediately in front of the promoter and often even overlapping the promoter. This site is referred to as the | Operator site | Enhancers are the binding sites for the | Gli proteins | DNA methylation, adding a methyl group to DNA nucleotides, in vertebrates ensures that | Specific methylation patterns are passed onto progency cells. | Histones are tightly packed into ________, which are located within the DNA. | Chromatin fibers | In gene regulation, negative control is exerted by a | Repressor | In gene regulation, a gene is “turned on’ by a | Activator | Small RNAs can regulate gene expression. One type, called micro RNA (miRNA), acts by binding directly to | mRNA | What must happen for transcription to be initiated | RNA polymerase has to have access to the DNA double helix and must be capable of binding to the genes promoter | When E. Coli cells produce the amino acid tryptophan, a cluster of five genes is transcribed together. This cluster of genes is referred to as the | Trp operon | The proteins necessary for the use of lactose in E. coli are collectively called the | Lac operon | Messenger RNA molecules are copies of DNA; they travel to the ribosomes to direct the assembly of | Polypeptides | The coded order of nucleotides in a DNA specifies the order of specific amino acids to be assembled into a polypeptide chain. The code is therefore called the ______ code | Genetic | Gene _______ refers to the combined processes of transcription and translation. | Expression | When multiple snRNPs combine to form a larger complex called a ______ the intron loops out and is excised. | Spliceosome | The connection that exists between genes and hereditary traits requires the