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| Acquired and Inherited Traits - Laws of Inheritance |
Acquired traits are the one that a person develops during his lifetime. These are not passed from one generation to another. On the other hand, inherited traits are present in the person since the time of his birth and are passed on from one generation to another.
Acquired Traits
An acquired trait is the character developed in an individual as a result of environmental influence. These traits are not coded by the DNA of a living organism and therefore cannot be passed on to future generations.
Darwin, Lamarck and Acquired Traits
Lamarck initially hypothesized that the acquired traits can be passed on from parents to offsprings making the organism more suitable to the environment. Darwin, later on, removed this hypothesis from his publication – Theory of Evolution, once he had enough evidence to prove that the acquired traits are not passed on from one generation to another.
E.g. an offspring born to a bodybuilder need not necessarily have extremely large muscles. This is because the muscles were acquired by the bodybuilder during his lifetime.
Inherited Traits
These are the traits that are inherited from the parents to the offspring. Hair, skin, eye colour, body type, height, and susceptibility to certain diseases are some of the examples of inherited traits in humans. The inherited traits of an individual are determined by their genes.
A single cell in a human body contains 25,000 to 35,000 genes. These genes carry the traits inherited by an individual from his parents.
Gregor Mendel explained the concept of inherited traits in his experiments with the pea plant. He depicted that the traits that are visible in the phenotype are called the dominant traits, while the traits that are not visible are known as the recessive traits.
Mendel explained the inherited traits by the following laws of inheritance:
- Law of Dominance: When two alternative forms of character are present in an individual, only one form expresses itself in the F1 progeny and is called the dominant trait, while the form that does not express itself is called the recessive trait.
- Law of Segregation: The alleles do not show any blending and are recovered as such in the F2 generation, though one of these is not shown in the F1 generation.
- Law of Independent Assortment: When two pairs of traits are recombined, segregation of one pair of characters is independent of the other pairs of characters during gamete formation.
This was an overview of the acquired and inherited traits.