Genetics
Genetics is the branch of biology which deals with the mutation, heredity and structure of genes of various organisms including humans. The first seed of genetics was sown by Gregor Mendel. He stated the fundamental laws of inheritance in living world but before we discuss that stuff we need to know that what is the basic structural system of genetics and exactly what are the terminologies used in this peculiar branch of science.
Genes and the laws of inheritance
Genes are the basic molecular unit of heredity in any organism. It is a structure which passes the factors of inheritance of parent organism into the offspring. They are bonded together in complex structures of DNA or deoxyribose nucleic acid which contain the code of genetic programing. These acids are blended together in long chains called chromosomes these chains are the nuclear components of special organisation, individuality and function. In a diploid cell their are two types of chromosomes Sex chromosomes and autosomes. Sex chromosomes decide that the foetus will be male or female. Females have XX sex chromosomes and males have XY chromosomes. These autosomes and sex chromosomes exist in pair of 23 in male and female gametes. Their are 22 pairs of autosomes and 1 pair of sex chromosomes during the fertilisation process these combine to form 46 pairs of chromosomes. These chromosomes are in form of dark matter called chromatin fibre.
Now before we enter in the world of inheritance let us talk about DNA and RNA this video will provide you a deep info about it
Now we know that what are DNA and RNA lets talk about inheritance.
These basic laws were given by Mendel and thus he is called father of genetics.
Law of segregation- This law states that only one allele or independent gene is expressed from a group of alleles during meiosis and thus is dominant. By this each pair of chromosome bears only one allele of particular character.
Law of independent assortment- When more than one pair of contrasting characters are brought in one individual, the entry of one pair of alleles separates independent entry and assorts independently of any other pair.
Law of dominance- In a offspring only in one allele express it self and prevents the expression of other. And is called dominant and other is called recessive.
Now we know that what are DNA and RNA lets talk about inheritance.
These basic laws were given by Mendel and thus he is called father of genetics.
Gregor MendelLaw of segregation- This law states that only one allele or independent gene is expressed from a group of alleles during meiosis and thus is dominant. By this each pair of chromosome bears only one allele of particular character.
Law of independent assortment- When more than one pair of contrasting characters are brought in one individual, the entry of one pair of alleles separates independent entry and assorts independently of any other pair.
Law of dominance- In a offspring only in one allele express it self and prevents the expression of other. And is called dominant and other is called recessive.
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