The Role of Genes in Human Characteristics
Understanding Genes and DNA
Genes are segments of DNA that contain instructions for making specific proteins, which ultimately determine our physical characteristics. Let's break down how this fascinating system works!
DNA (Deoxyribonucleic Acid) is like a blueprint that contains all the information needed to build and maintain an organism.
Key Components:
- DNA is made up of four bases: Adenine (A), Thymine (T), Guanine (G), and Cytosine (C)
- These bases pair up (A with T, G with C) to form the famous double helix structure
- Genes are specific sequences of these bases that code for particular traits
Inheritance Patterns
Our genetic makeup comes from both parents, with each parent contributing one copy of each gene. This creates interesting patterns of inheritance:
1. Dominant and Recessive Traits
- Dominant genes show their effect even if only one copy is present
- Recessive genes only show their effect if two copies are present
Brown eyes (B) are dominant over blue eyes (b)
- If you inherit BB or Bb → Brown eyes
- You need bb to have blue eyes
2. Codominance
- Both alleles are expressed equally
- Neither is dominant over the other
Athletic Performance and Genetics
Physical Traits Influenced by Genes:
- Muscle fiber type composition
- Height potential
- Body type (ectomorph, mesomorph, endomorph)
- Aerobic capacity
