Preambule
Before we discuss more about Genetics. We need to know what the purpose of studying Genetics. The aim of our study genetics so that we can know the exact mechanism of inheritance of parental (Parent) on Filial (Descendants), what is inherited and what is influencing and influenced by heredity. Genetics was originally coined by An Austrian scientist named Johann Gregor Mendel. (1822-1884). Mendel grew up in the farm so he has agricultural science. Then at age 21, he became a monk and then take the test to become a teacher but failed. And then he continued his education at the University of Vienna. There he met the famous physicist, Christian Doppler. And the famous botanist Franz Unger. Doppler teaches that as a scientist to be fond of experimenting and Franz Unger also interested about Mendelian inheritance and provide a challenge to apply mathematics in biology and even then the challenge is answered by Mendel in 1859.
Experiments Mendel's Laws of Inheritance and nature.
Mendel in his experiments using peas. Nuts used pea because he has properties that are easily observed, Cheap and has a short generation time. But before that Mendel should look for seed that really pure strains by means Crossing Homozygous dominant plants with each other. These seeds can then be used effectively. In his first experiment, he only saw the obvious properties only, ie flower color, location of flower, seed color, seed shape, pod shape, pod color and stem length. The way he crossed the white flowers and purple flowers by cutting the white flower stamens and pollen stick on white flowers. Then, the resulting pods planted. The results are all purple flowers and left self-pollinated. Here are the details of the results of Mendel's experiments.
Hence he argued Inheritance Law commonly called Mendel's Law. Mendel's laws are divided into Mendel's Law I and II. Mendel's first law, also called the Law of Segregation. This law states that the two alleles for a heritable character segregate (separate) during gamete formation and end up at different gametes. And Mendel's Second Law is commonly called the Law of Segregation states that every free pairs of alleles segregate independently of other pairs of alleles during gamete formation. To understand more about Mendel's Law Concerning please read Cleavage Sel.
Monohibrid Crossing
Monohibrid cross is a cross that only observes one character. Examples Crosses between plants of red roses and white roses.
Dihybrid cross is a cross that only observe 2 properties. The following example dihybrid crosses.
Polihibrid Crosses
Polihibrid cross is a cross where many properties were observed. The following example Polihibrid.
Test Cross
Test Cross is a cross between an individual with an unknown genotype with a homozygous recessive individual with genotype. The following example Testcross.
Backcross is a cross between to Filial One parent was. Human prohibited from backcross. Animals that are allowed and Plants. The following example backcross.
Resiprok Crosses
Resiprok cross is a cross over with the opposite sex. There is no difference between a regular cross because his genes are not sex linked. Here's an example of a Respirok Crosses
In fact, many crosses phenotype results not in accordance with Mendel's Law. However, when considered in the figure is a variation of phenotype in Mendelian Law. So-called Mendelian Law Moot deviation. The following example Mendelian Law Moot deviation.
Incomplete Domination / Intermediates
In this cross, allele Domminan not cover all of the recessive allele. Individuals who are heterozygous consequently have half a recessive trait. The following example Intermediates Crosses
Atavism
Atavism is the emergence of a cross which influenced the nature of the interaction of several genes. Atavism example can be seen in chicken's comb. The following example atavism Crosses.
Cryptomery
Cryptomery is the hidden nature of the dominant gene, if the gene is dominant stand alone. However, if the dominant gene interacts with other genes will mncul dominant trait dominant gene that were previously hidden and Phenotypes obtained Comparison 9: 3: 4 The following example Cryptomery Crosses.
Dominant epistasis is a cross which covered the Dominant alleles of genes with other genes work and have a phenotype ratio of 12: 3: 1 The following example Epistasis Dominant Crosses.
Polymery
Polymery is a form of gene interaction are cumulative (each add). Polymery caused by the interaction between two or more genes. So-called double-gene trait. The following example Polymery Crosses.
complementary
Is the complementary interaction of several genes that are complementary. This interaction can be called a double recessive gene epistasis also because if one is homozygous recessive gene, the appearance of a character by another gene to be imperfect / blocked. Comparison of phenotype is 9: 7 Here is the example of Complementary Crosses.
that's first Post About Genetics. The next post will discuss more about Genetics. Do not forget to send the answers of Biology Quiz 1 and send the answer to parawangsaa@yahoo.com in Docx format soon! Thank you!
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