Animal tissue DNA structure and function

Chromatin Lab Report

The use of DNA in today's world is very obvious, and the ability of the researcher and scientist to successfully manipulate this source of information to contribute to learning and understanding is great and powerful. DNA is found amongst chromatin which is found in certain types of fatty cells. Chromatin is key to the design of cells as it provides blueprints on how individual cells can be constructed. Since the packing structure of DNA is very dense this chemical reaction provides an understanding of how cellular relationships unfold and manifest.

DNA must be removed from the Chromatin which is stored as nucleosomes as the DNA strands wrap around these cellular structures. Saline provides an excellent solution to help separate these bonds and provide the isolating power to extract DNA for further examination. To salinize the targeted substance a constant and increasing amount of saline solution is added to the tissue and is further isolated by centrifuge and other mechanical stirring methods. Once the saline solution has done its job by reducing the strength of the chemical bonds between the protein and the DNA, the DNA can be more readily isolated by adding ethanol to the mixture, which is very highly soluble and allows the DNA to readily precipitate and become ready for extraction.

It is useful to look at animal and plant cells to truly gain a better understanding of how this process works and can be performed successfully. There are different steps to take when extracting this information from plant cells and this method will be examined as well to examine the amount and types of genetic material that are present in these types of organisms.

Methods

To accomplish this task, 50 grams of fresh calf liver was taken as the targeted sample to extract DNA using the aforementioned techniques. 250 ml of EDTA-saline was added to this tissue sample to begin the process and was summarily mixed in a blender. This mixture after a brief waiting time was filtered through cheesecloth and then distributed in 7-50 ml plastic centrifuge tubes. These tubes were spun in the centrifuge for 15 min and 2000 rpm and the supernatant was thrown out and new EDTA saline was added to repeat the salinization process. The tubes were then centrifuged for 15 minutes at 2,000 rpm and the resulting supernatant was discarded and replaced with an equal volume of EDTA-saline. The pellet was manipulated by gentle stirring and a brief 5-second vortex, and then centrifuged again for 15 minutes at 2,000 rpm. The supernatant was once again discarded, replaced with 40 mL of 2.6 M. NaCl, and the solution was gently stirred. The solution was then decanted into an Erlenmeyer flask, covered with Parafilm, and shaken at room temperature at the highest speed for ten minutes. After shaking, the solution was added to a 50 mL plastic centrifuge tube and centrifuged for 5 minutes at 2,000 rpm and the supernatant was poured into a beaker. To this supernatant, enough cold 95% ethanol was slowly added so the resulting concentration would be 70% ethanol. The sponge like -DNA that precipitated was picked out and put into a flask.

To understand how this process takes plant in the plant world, strawberries were used to examine this process. Two strawberries were mashed together into a fine pulp and placed into a 250ml container. A saline solution was added and then the mixture was stirred rapidly and with force for five minutes. The next ten minutes were spent filtering this mixture through multi-layers of cheesecloth. This was then transferred to a test tube and ethanol was added to the mixture . DNA was then extracted and taken as a sample.

Results

The results of this experiment suggest that this method of manipulating animal tissue to extract DNA is very simple and produces results. Since this is a basic experiment that focuses on developing clinical skills, the results of the experiment were used to help guide the processes and methods which produced the results. Ethanol after a post-saline bombardment and centrifuge, has a very strong effect on removing the DNA substance from the sinuous animal tissue that was used to provide the sample.

Ethanol provided an easy means to extract genetic material from plant life. As the ethanol was added a distinct and clear layer separated from the reddish mass of the mixture which provided the sample for DNA.

Discussion

The main revelations of this lab report suggest that true experiment when dealing with any substance and not just DNA is denotes a certain standard operating procedure that can be used as a tool and predict events. A liver sample used in this experiment does not contain much genetic material in relationship to other sources, so being able to retrieve this material in such a fashion suggests that a fundamental and rudimentary understanding of basic lab skills have been reached and understood.