ELECTROPHORESIS Essay Example | Topics and Well Written Essays - 1500 words

ELECTROPHORESIS - Essay Example These are size, voltage, supporting media and buffer (electrolyte). Smaller molecules travel faster than larger molecules while high voltages cause faster migration than lower voltages. However, there is a limit to the voltage that can be used as very high voltages cause the gel to melt and affect resolution. Various solid supports have varying pore sizes and sieving properties thereby affecting the rate of mobility. The lower the strength of the gel the bigger the pore size and vice versa. The buffer, which is a function of pH, also affects mobility and separation. Therefore, the success of the procedure depends on the correct choice of buffer. There are two main forms of electrophoresis namely moving boundary electrophoresis and zonal methods (Holme and Peck 1998, p. 133). The moving boundary method uses a U-tube that contains the analyte in the lower portion of the U while the arms contain the buffer. An electric potential is directed to the buffer and the movement of the boundary with time matches the velocity of migration of the analyte. The most common application of the moving-boundary electrophoresis is during the investigation of the physical traits of molecules as well as in large preparative processes. Conversely, zonal techniques involve the application of the analyte on a large area of supporting medium. They are named according to the supporting medium used and include the various types of gel electrophoresis (agarose gel, SDS-PAGE etc), capillary electrophoresis, affinity electrophoresis, and immunoelectrophoresis (Gault and McClenaghan 2008, p. 169). They are often employed in the separation of proteins cont ained in serum and urine, haemoglobin, isoenzymes, and nucleic acids. Electrophoretic equipment may vary in appearance, but all of them retain a common basic design that includes a tank, supporting media, an electrolyte compartment, electrodes, a stable supply of voltage, and safety gadgets. A cover is often included to minimize

Assessment Accommodation Research Paper Example | Topics and Well Written Essays - 500 words

Assessment Accommodation - Research Paper Example Accommodation is a word that can be described as an adjustment of the certain environment or a curriculum format to allow an individual to have an access to the learnings that he could gain from it or to somehow to complete the assigned tasks. An example of accommodation is the use of sign language in the teaching-learning process in order for the student to understand the lesson. If accommodation is known to be the â€Å"adjustment† or â€Å"alteration† of the curriculum to accommodate the student’s needs, the modification is the â€Å"change in the curriculum† for the students who cannot go with the actual comprehension process during the class discussion. An example of this is the reduction of the number of assignments for a certain student who has a lower level of comprehension compare to an average student. There are times when teachers commit the mistake of thinking she is in a classroom with the homogenous type of students. However, in reality, students, in general, are heterogeneous. Students have different needs and different weaknesses. Take this status-quo for instance: â€Å"Based on Census and Immigration and Naturalization Services records, it is estimated that there are79 million school-age language minority children in the United States. This bilingual population is distributed throughout the United States with heavier concentrations in the southwest and northeast. The highest concentration is in the large urban areas.† (http://www.teachervision.fen.com) You need to be sure that your student can understand the language or the vocabulary level that is being used in discussing the lesson. If not, it is important to teach them first the essential vocabulary that they need to understand.  Ã‚