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A paper on the disease scurvy
Ascorbic acid determination
Introduction of vitamin c lab report
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Recommended: A paper on the disease scurvy
Vitamin C Content of Apple Juice
Introduction
Complete lack of ascorbic acid (a.k.a Vitamin C) in the diets of humans and other
primates leads to a classic nutritional disease, scurvy. This disease was widespread in
Europe during the fifteenth and sixteenth centuries, but it is rare today. Ascorbic acid is
widely distributed in nature, but it occurs in extremely high concentrations in citrus and
green plants such as green peppers and spinach. Ascorbic acid can be synthesized by all
plants and animals, with the exception of humans, other primates, and guinea pigs.
Therefore, vitamin C must be present in our dietary substances.
The fundamental role of ascorbic acid in metabolic processes is not very well
understood. There is some evidence that it may be involved in metabolic hydroxylation
reactions of tyrosine, proline, and some steroid hormones, and in the cleavage-oxidation
of homogentisic acid. Its function in these metabolic processes appears to be related to
the ability of vitamin C to act as a reducing agent.
The adult Recommended Daily Allowance f vitamin C is 70 mg per day. Some
scientists and physicians have suggested doses up to 1 to 3 grams per day in order to help
resist the common cold. Deficiency of vitamin C results in swollen joint, abnormal
development and maintenance of tissue structures, and eventually scurvy.
Determination of vitamin C in biological fluids such as bolld and urine is difficult
because only small amounts of the vitamin are present and many interfering reducing
agents are present. Substances containing sulfhydryl groups, sulfite, and thisosufate are
common in biological fluids and react with DCIP, but much more slowly than ascorbic
acid. The interference by sulfhydryl is often minimized by the addition of
p-cholormercuribenzoic acid.
Materials and Supplies
Apple Juice
Metaphosphoric acid/ Acetic acid solution 4%
Unknown ascorbic acid in metaphosphoric acid/acetic acid solution, .5mg/ml
2,6 dicholorphenolindophenol solution in water
Ascorbic acid oxidase, lyophilized water
Experimental Procedure
Standard Ascorbic Acid Solution
Fill a microburet with DCIP solution. Using a pipet, transfer 1.0 ml of the ascorbic acid
standard solution to a 50 ml Erlenmeyer flask containing 5 ml of 4% metaphosphoric acid
solution. Read and record the initial reading on the buret. Titrate by rapid, dropwise
addition of DCIP from the buret while mixing the contents of the flask. Add DCIP
solution until a distinct rose-pink color persists for 15-20 seconds. Record the final
reading on the buret. Repeat this procedure twice more, each time with a fresh 1.
We then took 1ml of the 10% glucose solution again using the glucose rinsed pipette and added it to test tube 1, we then filled the H2O rinsed pipette with 9ml of H2O and added it to test tube one; making 10ml of 1% solution.
Each subsequent trial will use one gram more. 2.Put baking soda into reaction vessel. 3.Measure 40 mL vinegar. 4.Completely fill 1000 mL graduated cylinder with water.
Then, I added 8 drops of concentrated phosphoric acid to the mixture. swirling it a few times. Then, I carefully took the flask to the station as I avoided trying to breath the vapors of the acetic anhydride. I put the e-flask into the beaker of water sitting on the hot plate in order to heat it for seven minutes. Once the seven minutes was up, my partner carried the e-flask to the fume hood, and added 3 mL of de-ionized water to the flask. She swirled it for a couple of minutes there. She brought it back tot he station where I gradually added 60 Ml of de-ionozed water to the mixture while my partner stirred the mixture constantly. I was able to see some of the aspirin beginning to form. In order to complete the crystallization process we cooled the flask in an ice-water bath from 4:00 until 4:20. As we waited I began to set up our filtration system. I used a ring stand, right angel clamp, three finger clamp, Buchner funner, filtering flask,rubber tubing, and filter paper in the Buchner funnel. I turned on the aspirator and pored some water over the filtering paper in order to create a good
Labels on tryptophan supplements recommended a dosage of 500 to 1500 mg once or twice a day.
We were then to make a base solution of 0.7 M NaOH. In order to standardize
“Success consists of going from failure to failure without loss of enthusiasm”- Winston Churchill. Winston Churchill achieved success from failures, and he also achieved success through his speeches. His speeches are what contributed to his success during World War 2. His speeches follow the criteria of an effective speech. The criteria to critique a speech are to find the speech objectives, the audience and context of the speech, the speech content and structure, and analyzing the delivery skills and techniques. The speech objectives are to “educate, to motivate, to persuade, or to entertain” (Dlugan 1). The audience and context of a speech show “where and when the speech is being delivered” (Dlugan 1), and the features of the
of distilled water. For the 1M solution I added 50 cm3 of HCl and 50
When one hears the three words: vitamins, nutrients, and minerals, they think of one thing-being healthy and noticing what your intake is daily. Nutrition is all about vitamins and nutrients. Firstly, vitamins are an organic compound required by the body in small amounts of metabolism, to protect health, and for proper growth of children. Vitamins also assist in the formation of hormones, blood cells, nervous systems chemicals, and genetic material. There are 13 well-identified vitamins. Some examples of the 13 well-identified vitamins are: A, D, E, and K-fat contained foods, B, C-consumed immediately. A well known and commonly used in commercials for orange juice vitamin is vitamin C. Vitamin C or ascorbic acid is important in the synthesis and maintenance of connective tissues. The lack of vitamin C will result in a sickness called scurvy. Scurvy harms the gums, mucous membranes, and the skin. Another well-known vitamin and is also used to commercial to give more information about this beverage is the vitamin in milk. The vitamin in milk is vitamin D. If you do not drink milk and obtain this vitamin, your bones and teeth will become soft and weak. Lacking one or more of the 13 well-identified vitamins will cause sickness and weakness to your body. Secondly, nutrients are how the body assimilates certain compounds. Nutrients are classified in 5 major groups: proteins, carbohydrates, fats, vitamins, and minerals. One of the five nutrients is carbohydrate. The carbohydrate group principally consists of sugar, starch, dextrin, cellulose, and glycogen. In more basic terms, carbohydrates are sugars needed by human and other living organisms. Some types of foods that contain carbohydrates would be candies, ice cream, fruit juice, soda, chocolate bars etc. Lastly, vitamins are connected to minerals. Minerals are also a very important part of a healthy person. There are 11 major groups of minerals. They are: calcium, chromium, copper, iodine, iron, magnesium, manganese, phosphorous, potassium, selenium, and zinc. All these terms look very familiar if one has taken chemistry. These are the elements of our world. One of the more common minerals that most people have heard of is calcium. Calcium also helps with the structure and strength of teeth and bones. Vitamins and minerals work together to help humans maintain a healthy body. For example, vitamin D works with calcium to help for and maintain the strength of teeth and bones.
I shall add water as that is the only way I can find out how
I used a 5ml syringe to measure the DCPIP solution. Although I used a syringe to make sure it was accurate, some of the DCPIP solution remained on the side of the syringe; this decreased the accuracy of the measurement as I may have added different amounts in each test. When I put the DCPIP solution into the boiling tube, some didn’t go down and remained on the side of the boiling tube. Next time I will wait for all the DCPIP solution to go down to the bottom of the boiling tube to ensure that I am adding each juice to the same amount of DCPIP solution.
Lucas devotes a section of chapter one to talking about the history of public speaking stating that every culture has some word equivalent of the word speaker. Lucas then goes on to tell the similarities and differences between public speaking and conversation. Stephan Lucas then goes on to explains in this chapter that nervousness and stage fright are among the leading causes for the fear of public speaking. But he then assures us that nervousness is normal, and a welcomed part of speech giving. Lucas proves his point by saying, “If you feel nervous about giving a speech, you are in very good company. Some of the greatest public speakers in history have suffered from stage fright, including Abraham Lincoln, Margaret Sanger, and Winston Churchill” (Lucas, 2012 pg. 9). Lucas says that you should not run from your nervousness, but instead try to turn it into a positive nervousness. Lucas then goes on to give six ways to turn the negative nervousness into positive nervousness. They are acquiring speaking experience, preparation, positive thinking, visualization, realizing you’re nervousness isn’t visible and not expecting perfection. Now that Lucas has touched on the history, fears, and possible rewards of public
second test tube also add 6 mL of 0.1M HCl. Make a solution of 0.165
Vitamins, a group of organic substances required in our diets in small amounts for growth and nutrition, are usually found in foodstuffs or taken as supplements. Yet vitamins probably present a wider gap between myth and reality in the layman's understanding than almost any other area of our diet. Surveys have found that while a majority of Americans do take vitamin supplements on a regular or occasional basis for reason of health concerns, there exists enormous confusion about the actual purpose and benefits of this practice ("Use of Vitamin and Mineral Supplements in the United States," 1990:161). Most people have a recognition that Vitamin C prevents scurvy, that Vitamin A is found in fish-liver oils, or that Vitamin D is found in dairy products; many people believe that Vitamin E preserves youth and prevents sterility, or that Vitamin C can present colds and cancer. Beyond this, however, there is still considerable ignorance and widespread myth.
I have also learned about different types of audiences and speeches including persuasive, informative, entertaining and delivering special occasion speeches. It came to my attention that whenever I was making these presentations or speeches, I needed to do so with confidence, consistence and practice before the actual presentation and completely eliminate the element of panic. It was also clear that capturing the attention of the audience and engaging them in the whole process, it was necessary to have a very strong introduction and also try and use visuals to deliver the message. It was therefore vital to respect each person’s diversity and cultural values (Lucas, 2011).