Bio 280 Exam 2 Questions and Answers

How many chromosomes are found in prokaryotes? Answer one What is another place that can have DNA in prokaryotes? Answer plasmid Bacteria generally have a? Answer single large chromosome Super Coiled DNA is Answer DNA packed and coiled which is held together by proteins. It is not bounded by a membrane. Plasmids Answer -Extrachromosomal circular DNA -Contain genes which are not necessary for the organism's survival but which may be useful to it (e.g antibiotic resistance genes, genes for enzymes which degrade pollutants for consumption by the cell, etc.). -Can be transferred 'horizontally' (from mature cell to mature cell) - Used as vectors for transferring DNA in genetic engineering Ribosomes Answer - Used for constructing proteins from messenger RNA (mRNA) (more on this later) - In two parts and made up of proteins and ribosomal RNA (rRNA) Poly beta-hydroxybutyrate (PHB) granules Answer a chemical some bacteria produce to store carbon and energy, much like we do with fats. Its significance to humans is that it is essentially biodegradable plastic