PRATICAL WORKSHEETS - Essay Example

Practical Worksheet Practical Worksheet DNA (Deoxyribonucleic acid) is a ladder that comprises of fourteen bands. The base pair of these fourteen bands may vary from 100 to 3000bp. Both in the well 1 and well 2, extracted DNA is having the size of the base pairs of about 350bp. In the similar manner, both in the well 4 and well 5 similar base pair size of H-DNA of about 300bp is present.2. After going through various steps of DNA fingerprinting, it is quite evident that the DNA samples collected from the crime sight contains base pair bands that range from 600 to 700bp.

The base pairs are in the bands with 6th and 7th location of the DNA ladder. The DNA samples collected from suspects have the similar size of bands of about 1000 to 1100bp. However, band size of about 800 to 900bp and 1300-1400bp were also seen in the samples 1 and 2. On the other hand, the DNA fingerprinting shows that suspect 3 DNA has base pair band size of about 600-700bp that is similar to the band size of the DNA attained from the crime sight. Thus, is it quite clear that the DNA samples from the crime sight and suspect 3 DNA samples are same and suspect 3 has interaction with the crime sight.3. Tris-borate-EDTA and Tris acetate-EDTA are the basic buffing compounds that are used to characterize the DNA molecules.

Tris acetate-EDTA is to characterize smaller molecules of DNA whereas Tris-borate-EDTA is taken to analyze the portions of DNA. In order to maintain the pH of the DNA fragments, DC voltages of about 4-10V per centimetre is applied. On the other hand, it also enhances the DNA fingerprinting by lowering the movement of portions of DNA. In this way, bands with enhanced visibility and broad view can be created. On the other hand, as the concentration of gel increases the movement of fragments also decreases.

Molecular biologists use DNA electrophoresis and find it a better method to differentiate different DNA fragments, as different segments of the DNA molecule show different characteristic when charge is applied. The DNA matrix is first into a solution that has higher concentration of buffer and DC voltages are then passed. As the presence of phosphate groups makes the DNA molecules to have negative polarity, it attracts the positive terminal. The ratio of the mobility depends on the strand size of the DNA molecule.

If the strand size of the DNA is smaller it will move easily and faster after applying electric current as compared to the longer stands DNA. In order to make the DNA samples more visible a florescent compound like ethidium bromide is added to make the strands and molecular visible in the presence of UV light.4. Temperature has a deep impact on the reactions within the enzymes. Temperature either fastens the reactions of slows down the reaction within the enzymes. With the increase in temperature the reaction within the enzymes becomes faster and more and more enzymes become denatured.

With only a mere increase of 10 degrees in temperature makes the enzymes to increase their functionality two times (form 50 folds to 100 folds). The optimum temperature for the tyrosinase enzymes to work efficiently is about 35-36 degrees on the Celsius scale. The increase in the activity of the enzymes is due to the higher kinetic energy due to the collisions between the molecules. 5. PH levels also influences the enzymes to respond in a more appropriate manner. Enzymes work better at optimum pH.

From the pH level of 1 to pH of 4, the enzymatic process becomes inefficient. This means as the pH level increases the enzymatic process of tyrosinase become more active. On the other hand, when the pH level increases to more than 6, the enzymatic processes become inefficient. That means that the pH level of 4 to pH level of 6 is the optimum pH for the enzymatic process. Most of the enzymatic processes are semi or completely reversible, the broken bods due to the alteration in the pH level re-bond as the pH become optimum.

Thus, pH can also characterize various enzymes.