Variation? Heredity?

Variation refers to the differences in traits or characteristics among individuals within a population or species. These variations can be caused by genetic factors, environmental factors, or a combination of both.

Heredity refers to the passing on of traits or characteristics from parents to offspring through genetic information. This genetic information is contained in the DNA of an organism and determines its physical and behavioral traits. Heredity plays a key role in determining the variations seen within a population or species.

Variation

- Definition: Differences in traits among individuals of the same species.
- Causes:
- Genetic: Differences in genes (e.g., mutations, allele variations)
- Environmental: Differences in the environment (e.g., temperature, nutrition, pathogens)
- Interaction: Complex interplay between genes and environment
- Types:
- Continuous: Gradual differences in traits along a continuum (e.g., height, weight)
- Discontinuous: Clear-cut differences in traits (e.g., blood type, eye color)

Heredity

- Definition: The passing of genetic information from parents to offspring.
- Mechanisms:
- DNA: Carries genetic instructions inherited from parents
- Mitosis: Cell division that distributes genetic material equally to daughter cells
- Meiosis: Cell division that generates gametes (eggs and sperm) with half the genetic material of parent cells
- Patterns:
- Mendelian inheritance: Predictable patterns of trait inheritance based on dominant and recessive alleles
- Polygenic inheritance: Traits influenced by multiple genes
- Epigenetic inheritance: Modifications to gene expression that can be passed on to offspring without changing DNA sequence