2: THE HISTORY OF CYTOGENETICS Flashcards
- expressed it in the famous aphorism “Omis cellula e cellula” (all cells come from cell)
All organisms will inherit their genetic information specifying their structure and function that comes from their parents.
RUDOLF VIRCHOW
- “Heredity appears as a consequence of the genetics continuity of the cells by division.”
WILSON
Observations on the germ cells made by Van Beneden, Flemming, Strasburger, Boveri, and others gave support to the theory of continuity of the germ plasm proposed by ________ in 1883.
Weismann
This theory stated that the transference of hereditary factors from one generation to the next takes place through the continuity of what he called ‘germ plasm’, located on the sex elements, and not through somatic cells.
theory of continuity of the germ plasm by Weismann
is a combination of egg cell and sperm.
Germ cells
The discovery of fertilization in animals, foreseen by __________
O. Hertwig
The discovery of fertilization in animals, foreseen by O. Hertwig but observed directly by H. Fol (1879), and in plants, by __________ led to the theory that the cell nucleus is the bearer of the physical basis of heredity.
Strasburger
The discovery of fertilization in animals, foreseen by O. Hertwig but observed directly by H. Fol (1879), and in plants, by Strasburger, led to the theory that the cell ________ is the bearer of the physical basis of heredity.
nucleus
- postulated that chromatin, the substance of the nucleus that constitutes the chromosome, must have a liner organization.
ROUX
Roux postulated that chromatin, the substance of the nucleus that constitutes the chromosome, must have a _____________________.
liner organization
- stated that the hereditary units are disposed along the chromosomes in an orderly manner.
WEISMANN
The fundamental laws of hereditary were discovered by ___________ in 1865, but at that time cytologic changes produced in the sex cells were not sufficiently known to permit an interpretation segregation of hereditary characters.
Gregor Mendel
Little attention was paid to Mendel’s work until the botanists ______________________________ in 1901 independently rediscovered Mendel’s laws.
Correns, Tschermack, and De Vries
_________ suggested that sex determination was related to some special chromosomes, this theory was later corroborated by Stevens and Wilsons (1905)
McClung (1901-1902)
The experimental demonstration of the chromosome theory of heredity was finally established by ___________________, but it was Morgan and his collaborators, Sturtevant, and Bridges, who assigned to the genes (Johannsen), or hereditary units, define loci within the chromosomes.
Boveri and Baltzer
The experimental demonstration of the chromosome theory of heredity was finally established by Boveri and Baltzer, but it was __________________________________________, who assigned to the genes (Johannsen), or hereditary units, define loci within the chromosomes.
Morgan and his collaborators, Sturtevant, and Bridges
Thereafter experimental research on heredity and evolution became a separate branch of biology which _________ in 1906 called “genetics”.
Bateson
___________ published his investigations into inheritance of pea plants.
Gregor Mendel
