Introduction
The purpose of the demonstration is to allow the students to get a "hands-on" opportunity to do a scientific experiment. The focus of the experiment should be getting as many students involved as possible, and to have fun with the experiment.

In the experiment, Blue Dextran is mixed with a dilute Phenol Red solution in a buffer containing sodium chloride and sodium acetate at pH 5.0. At this pH, the phenol red turns yellow (right in front of the students' eyes!). Upon mixing with Blue Dextran, the solution turns green. Application of the solution to a Pharmacia PD-10 column separates the green back into blue and yellow.

Materials and Methods
The following solutions will be needed:

* Blue Dextran, 3 mg/ml, in water
* Phenol Red, 10 mg/ml, in water
* 150 mM NaCl, 50 mM NaOAc, pH 5.0 (Equil. Buffer)
Note: you can purchase Blue Dextran and Phenol Red from Sigma Chemicals. Call 1-800-325-3010 for more information. Sigma product numbers are as follows: Blue Dextran/D5751 (5g/$66.80); Phenol Red/143-74-8(5g/$7.75)

The following equipment will be needed:

* Pharmacia PD-10 columns (at least 2)
Note: You can purchase PD-10 columns from Pharmacia (1-800-526-3593/ product number 17-0851-01/ Box of 30/$112.00)
* Powder funnels (1 per column)
* Ring stand with clamps
* P1000 and P20 Pipetmen/tips
* Disposable 12 x 75 mm test tubes
* Liquid waste container
* 25 ml or 50 ml plastic grad. cylinder

Experimental Procedure

1. Pre-equilibrate both PD-10 columns with at least 25 ml of equilibration buffer. This allows the second column to be used while with first column is being re-equilibrated.

2. Point out to the students beforehand that their eyes may play tricks on them. Let them think that magic is at work here. Add 1-2 ul of Phenol Red to 500 ul of equilibration buffer in a disposable 12 x 75 mm test tube. The solution turns yellow.

3. Ask the students if they know what color is made by the mixing of blue and yellow. Add 500 ul of Blue Dextran to the diluted Phenol Red solution to confirm their guess.

4. Transfer the green solution to the PD-10 column. Point out that the colors are separating from each other, but that only blue is visible at first.

5. Connect the powder funnel to the column. Add about 25 ml of equilibration buffer to the funnel and watch for the color separation. The students will notice complete separation of the blue from the yellow, with a white zone in between.

6. During chromatography, the students may have questions, and this is usually the best time to answer them, as well as to explain what is going on. A simple explanation of the theory is to compare the gel beads to "Wiffle Balls" and the difficulty or ease that big and small objects may have in fitting through the holes in the Wiffle Balls.

Labels: biochemistry, biotechnology, chromosomes, demonstration, genetic chromosomes, genetic engineering, project

Chromatography is a technique for:

separating mixtures of compounds
identifying unknown compounds
establishing the purity or concentration of compounds
monitoring product formation in the pharmaceutical and biotechnology industries



Chromatography is the science which is studies the separation of molecules based on differences in their structure and/or composition. In general, chromatography involves moving a preparation of the materials to be separated - the "test preparation" - over a stationary support. The molecules in the test preparation will have different interactions with the stationary support leading to separation of similar molecules. Test molecules which display tighter interactions with the support will tend to move more slowly through the support than those molecules with weaker interactions. In this way, different types of molecules can be separated from each other as they move over the support material.

Chromatographic separations can be carried out using a variety of supports, including immobilized silica on glass plates (thin layer chromatography), volatile gases (gas chromatography), paper (paper chromatography), and liquids which may incorporate hydrophilic, insoluble molecules (liquid chromatography).

Labels: biotechnology, chromosomes, genetic chromosomes, pharmaceutical, techniques

A calico cat is not a breed of cat, it is a color pattern. To be called "calico", three colors must be present: black, white and orange. Variations of these colors include gray, cream and ginger. A "true" calico cat has large blocks of these three colors.

In vast majority, calico cats are always female. Why? The answer is in its genetic. The calico color of the cats are sex-linked trait. Sex linked trait is a physical cahracteristic that is related to gender. As you know female gets her xx and male gets his xy.

The answer is: the genetic coding for displaying black or orange color is found on the X chromosome. The coding for white is a completely separate gene. Since females have two X chromosomes, they are able to "display" two colors (orange and black) and white, creating 3 colors. They can be male too (in rare case). In this situation, the cat has two X chromosomes and one Y chromosome (XXY). This condition is similar too klinefelter's syndrome as i already explained in previous post.

Labels: calico, cats, chromosomes, colors, genetic, klinefelter's, sex

There is a gene called CYP 17 in chromosome 10. This gene creates enzyme which able to break down cholesterol to its simple forms. We know that cholesterol is synonimous with poison. It causes death and some suffocating disease, that left you high and dry. Cholesterol itself is made from some hormones like testosterone, progesterone, cortisol, corticosterone, oestradiol. Without this enzyme, the pathway is blocked and the only hormones taht can be produced are progesterone and cortocisterone. People who lack a working of this gene cannot make other sex hormones, simply goes like if you genetically male, you look like girls.

Cortisol is one of hormones that made by this gene. It's used in integrating body and mind. It interferes with the immune system, changes the sensitivity of ears, eyes, and nose. It also alters body function. By definition, when you have a lot of cortisol in your veins, you are under stress. Cortisol and stress are also synonymous.

Although stress is caused by the outside world, such as heading on to exams or exhaustion. Stress is divided into two stressors: short term and long term. Short term stressors cause an increase in norepinephrine and epinephrine, both makes the heart beat faster and the feet go cold. Long term stressors that last for longer activate a different pathway that results in a much slower. High of cortisol also makes your immune system goes lack. That's why people who in high stress are more likely to catch colds and other infection. Cortisol is reducing the number and lifetime of lymphocytes.

In white blood cells cortisol is certainly involved in switching a gene called TCF, also on chromosome 10, which able to make its own protein, whose job to suppress another protein called interleukin 2 that puts white blood cells on alert. So cortisol, suppresses the immune system but makes you more susceptible to disease.

Labels: biology, cholesterol, chromosomes, cortisol, genes, lymphocyte, white blood cell

The X and Y chromosomes are known as the sex chromosomes, for the obvious reason that they determine the destination of human's gender. Simply, xx is for female and xy is for male. Everybody gets an X from his or her mother, but if you inherited y chromosome from your father you're male; if you inherited x from your father you're a female. Since men(XY) have no spare x chromosome, they are more likely to suffer recessive problems than women. Thus, haemophillia, colorblinndness and ilk are much more common in men's X.

This simple predestination can also go wrong and causing aneuplody. Aneuplody (abnormal number) of chromosomes. XXY syndrome and named by the Massachuset founder Klinefelter, a genetic disorder that is giving the patient 47 chromosomes in total (46 for normal).

Klinefelter's is a genetic disorder where the man has an extra x chromosome. Usually the patient has small testicle, low testosterone, tall and unpropotional body, and also teeth abnormalities. The disorder is the result of error that occured during the sperm forming during the meiosis

Labels: aneuplody, biology, chromosomes, genes

In every biochemical events in body, there are genes. If human body is a book, genes are just sentences of prose written over it. The entire of genetics complements is called genome. Matt Ridley, a British science editor, in his book Genome (1999) painted that if the genome is a book, there are twenty three chapters, called chromosomes. Each chapter contains stories, called genes. Each stories are made up of paragraphs called exons, which are interrupted by advertisements called introns. Each paragraph is made up of words, called codons. The letters of each word are called basses. Ridley whom wrote his book made up chapters that named after 23 chromosomes, exposed all information about each chromosome based on the number of chapter. In human body, the 23 chromosomes are made up by 22 autosomes and a pair of sex chromosomes (xx in female and xy in male). In size, the 22 pairs are numbered by the largest (number 1) to the smallest (number 22). The sex chromosome X is located between number 7 and number 8, while Y is the smallest.

Genes are located in a chromosome. In each chromosome, there are 400-4000 genes. Genes are written in three bases or called as codon. The 4 bases are Guanine, Cytosine, Adenine, and Thymine. The bases are written on long chains of sugar and phosphate called DNA. During the replication, A likes to pair with T and G likes to pair with C. For instance, the sequence of ACGT becomes TGCA in the copy form. Besides the gene is able to do replication, it is also able doing translation. The translation starts with the transcription of the gene into a copy by RNA with the same base-pairing process except that it uses letter U for uracil to pair with T. Then a ribosome moves along the RNA copy (messenger RNA) translating each codon into twenty different amino acids. Later, the chain of amino acids forms a protein. In conclusion, every protein is a translated gene. Protein itself also responsible to switch gene on or off for being promoter and enhancer of a particular gene.

Unfortunately, during replication mistakes are sometimes made. This is known as mutation. Although genes are small and tiny, this doesn’t mean genes are unimportant. If an error happens in a gene, this may caused flaw in body system. For example, when chromosome 3 is broken it caused a metabolic anomaly disease named alkaptonuria, or like the most famous genetic disease Huntington’s happens because of chromosome 4 mutation and when there is a complete lack in chromosome 4 it may causes rare Wolf-Hirscchorn syndrome, the chromosome 6 if it is broken can cause the problem of human intelligence. In genetic disorder, there is no 50-50 probability you get it or not. You either have mutations, in which case you get these genetic diseases, or you don’t.

But, the genetic doesn’t always work in that digital way. Sometimes, it depends on environment too. Like the case of asthma. There are 15 ‘asthma genes’ in all chromosomes (8 genes in chromosome 5, 2 each in chromosome 6 and 12, and 1 each in chromosome 11, 13, and 14). These genes are producing immunoglobulin E aka IgE. According to medterms.com, IgE acts as antibody in our body by eliciting allergen (allergic mucous). Most asthmatics are allergic to something. Asthma, eczema, allergy, and anaphylaxis are syndrome that triggered by IgE. So, that’s why allergic person has asphyxia.

Asthma itself is a chronic inflammation in bronchial tube and causing the tightening of the windpipe. How does it correlate with chromosome 5? ADRB 2 lies along in chromosome 5 and it responsible to produce beta-2-adrenergic-receptor which controls the bronchodilation and bronchoconstriction that cause the tightening in bronchus or windpipe. According to American Lung Association, feather, pollen, vigorous exercise, dust mites are the most common asthma triggers. No matter what triggers a person to have asthma, his or her asthma syndrome still triggered by IgE.

Sources:
Ridley, Matt. 1999. Genome. USA: Harper Collins.
Medterms.com
Wibowo, Daniel . 2005. Anatomi Tubuh Manusia. Jakarta: Gramedia.

Labels: asthma, biology, chemical, chromosomes, genes, genome