A gene is the unit of heredity in every living organism. Genes are encoded in an organism's genome, composed of DNA or RNA, and direct the physical development and behavior of the organism. Most genes encode proteins, which are biological macromolecules comprising linear chains of amino acids that affect most of the chemical reactions carried out by the cell. Some genes do not encode proteins, but produce non-coding RNA molecules that play key roles in protein biosynthesis and gene regulation. Molecules that result from gene expression, whether RNA or protein, are collectively known as gene products.
Most genes contain non-coding regions, that do not code for the gene products, but often regulate gene expression. A critical non-coding region is the promoter, a short DNA sequence that is required for initiation of gene expression. The genes of eukaryotic organisms often contain non-coding regions called introns which are removed from the messenger RNA in a process known as splicing. The regions that actually encode the gene product, which can be much smaller than the introns, are known as exons.
In molecular biology, a gene is a region of DNA (deoxyribonucleic acid) - or RNA (ribonucleic acid), in the case of some viruses - that determines the amino acid sequence of a protein (the coding sequence) and the surrounding sequence that controls when and where the protein will be produced (the regulatory sequence). The genetic code determines how the coding sequence is converted into a protein sequence. The protein-coding regions of genes are composed of a series of three-nucleotide sequences called codons. Each codon specifies a particular amino acid to be added to the protein chain; thus genes determine the protein's primary structure. Most genes are expressed in a two-stage process: first, the DNA is transcribed by enzymes known as RNA polymerases to produce an RNA molecule known as messenger RNA (mRNA), and second, the mRNA is translated by specialized cellular machinery known as the ribosome into a polypeptide chain that then folds into a functional protein. The genetic code is essentially the same for all known life, from bacteria to humans.
Through the proteins they encode, genes govern the cells in which they reside. In multicellular organisms, they control the development of the individual from the fertilized egg and the day-to-day functions of the cells that make up tissues and organs. The roles of their protein products range from mechanical support of the cell structure to the transportation and manufacture of other molecules and to the regulation of other proteins' activities.
2006-12-13 01:54:31
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answer #1
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answered by wengkuen 4
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Possibly, but genetic engineering is in its infancy. There is also a question of hormone therapy that was raised last year by the president of the Southern Baptist Theological Seminary. He said "I am absolutely confident that a large number of homosexuals are telling the truth when they say they did not choose that orientation," as well as that he opposes genetic manipulation of all kinds... but he went on to say that if a hormone therapy were developed for fetuses that would help them be born straight rather than gay, he would support its use, just as he would support medical treatment to give sight to the blind fetus (his words, not mine). Words such as his are one reason that some gay people would rather research on the causes of homosexuality not be done since it is not a disability in need of a fix or a disease in need of a cure. Their thoughts are that once the genes (it is most likely not a single gene) and possible additional factors such as pre-natal hormones that cause homosexuality are isolated, that those who dislike gay people will then say it needs to be 'fixed' or 'cured'. Once the field of genetic engineering reaches the point that it could be used on humans I doubt it would ever be used. Stem cell research would have likely matured to the point that it could cure many diseases, and hopefully people would have evolved enough to not think that a person falling in love with another person is somehow wrong or in need of being altered.
2016-03-29 05:40:38
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answer #2
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answered by Anonymous
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Genetic means the basis in which your genes express themselves, for example a genetic disease means a certain make up of your genes has predispositioned you to suffer from a certain condition, e.g autoimmune disorders
2006-12-13 01:52:09
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answer #3
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answered by Anonymous
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Genes are made up of dexyribonucleic acid in humans. While in some organisms such as selected viruses, the genetic information is encoded as ribonucleic acid.
2006-12-13 02:10:06
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answer #4
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answered by Arvin Al 2
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None. We are a long way from `making up` genes
2006-12-13 02:05:00
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answer #5
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answered by Jomtien C 4
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gene is the small fragment of DNA . It is a made up of repeating units of deoxyribonucleotides. This nucleotides are made up of nitrogenous base like purines(adenine&guanine) and pyrimidines (cytosine & thymine); pentose sugsr and a phosphate in case of DNA.
2006-12-16 01:25:22
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answer #6
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answered by carol 2
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Is made up ... what?
2006-12-13 01:48:52
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answer #7
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answered by CHESSLARUS 7
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