Genetics Flashcards
believed that reproduction of organisms originate through formation of miniature versions known as homunculus
preformationism
who and when was preformationism established
17th century by pythagoras and aristotle
each part of the body can produce ____________ that contribute to the formation of an offspring
gemmules
where did the idea of preformationism originate from?
parthenogenesis of insects, amphibians, and reptiles
sperm contains the miniature individual and only nourished by the ovum
spermists
thought the same and that the seminal fluid only stimulates it
ovists
criticized aristotle’s work by asserting “ex ovo omnia” - stating that all organisms come from eggs
william harvey (epigenesis)
organs of an organism that is frequently and continuously used becomes more developed and prominent
theory of use and misuse
modifications that an organism underwent in its life is due to the factors of use and misuse and will be preserved and passed on to the next generation
theory of acquired characteristics
there will be changes in the characteristics of organisms due to pressure exerted by the environment
theory of evolution and natural selection
2 types of cells in the body proposed by august weismann
autosomal or somatic cells, gametes
theory by august weismann that suggests there are 2 types of cells in the body
germplasm theory
cells that are responsible for sustaining the body
autosomal or somatic cells
cells that contain hereditary information
gametes
he disproved the concept of preformation using mice
august weismann
process of passing on of traits from parents to offspring through sexual or asexual reproduction
heredity or inheritance
presence of different frequencies of traits among individuals or populations
variation