epigenesis
Quick Summary
Epigenesis is a theory of development stating that organisms develop from an egg or spore through a series of processes where unorganized cell masses differentiate into organs and organ systems. This contrasts with preformationism, which suggested that a pre-formed organism existed within sex cells.12
Heredity refers to the process where offspring resemble their parents, but inherited potential interacts with and is modified by environmental factors. While a genotype conditions possible outcomes, epigenesis allows for a variety of expressions. Epigenetics, a related field, studies chemical modifications to genes that influence gene expression without altering the DNA sequence itself. These modifications can be heritable, though the exact mechanisms are still being researched.23
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zoologyEmbryology, or developmental studiesAlthough this epigenetic process is now accepted as characterizing the general nature of development in both plants and animals, many questions remain to be solved. The French physician Marie François Xavier Bichat declared in 1801 that differentiating parts consist of various components called tissues; with the subsequent…
Read MoreAlthough this epigenetic process is now accepted as characterizing the general nature of development in both plants and animals, many questions remain to be solved. The French physician Marie François Xavier Bichat declared in 1801 that differentiating parts consist of various components called tissues; with the subsequent…
Read More- heredityPreformism and epigenesis
A notion that was widespread among pioneer biologists in the 18th century was that the fetus, and hence the adult organism that develops from it, is preformed in the sex cells. Some early microscopists even imagined that they saw a tiny homunculus, a diminutive…
Read MoreA notion that was widespread among pioneer biologists in the 18th century was that the fetus, and hence the adult organism that develops from it, is preformed in the sex cells. Some early microscopists even imagined that they saw a tiny homunculus, a diminutive…
Read More