Inherited Traits and Expression of Traits

1. Inherited traits

Inherited traits are encoded in our DNA and passed on to the next generation, such as eye colour, height, skin tone, and hair colour. Variations arising from reproduction can also be inherited and may enhance an organism's survival. In sexually reproducing individuals, there are two copies of each gene. If these copies differ, the trait that is visibly expressed is called the dominant trait, while the one not expressed is the recessive trait. These variations can contribute to survival advantages or lead to genetic drift within a species.

2. Acquired Traits

Traits are expressed based on the information stored in DNA, which serves as the source for making proteins in a cell. A specific section of DNA, called a gene, provides the instructions for creating a particular protein. These genes are responsible for controlling traits in organisms.

As per Mendelian law, both parents contribute equally to their offspring's genetic makeup, providing a set of genes through chromosomes. Chromosomes are distinct pieces of DNA, not a single continuous strand. Each cell contains two copies of the chromosome set, one inherited from each parent. When germ cells combine during reproduction, they restore the normal chromosome number, ensuring the stability of DNA in a species. For example, consider the characteristic plant height. The height of a plant depends on the production of growth hormones, which are influenced by the efficiency of certain enzymes:

• Efficient enzymes produce more growth hormones, resulting in taller plants.
• Less efficient enzymes produce fewer hormones, leading to shorter or stunted plants.

Inherited Traits Examples:

Although every human being is unique, we share certain common characteristics with our family members and peers. Each person has a unique set of traits. Some traits are inherited from parents through genes, while others are acquired through observation and learning. These acquired traits are often influenced by a combination of environmental factors and genetic makeup.

• Tongue rolling
• Earlobe attachment
• Dimples
• Curly hair
• Freckles
• Handedness
• Hairline shape
• Green/Red Colourblindness
• Hand clasping