Embryology Flashcards
What is embryology
Development of an organism from a fertilised egg to birth.
Define phylogeny
Origin of a specie.
What was the contribution of William Harvey to embryology?
He was the first to observe blastoderm of the chick embryo.
Caspar Federch Wolf
Made detailed observations on chick embryos. He demonstrated how the gut arises the folding of an originally in different flat tissue and produces.
Ernst Haeckel
Considered that ontogeny is a short recapitulation of phylogeny.
…….abandoned his practice after reading “The Origin of Species” by ………
a) Ernst Haeckel
b) Charles Darwin
Democritusa
The Sex of an individual is determined by the the origin of sperm. Male from the right,testicle and female from the left.
Aristotle
First real embryologist!. In The Genaration of Animals he described the different ways that animals are born; oviparity(birds frogs, and most invertebrates), by live birth( viviparity, as in placental animals and some fish) ovoviviparity( production of an egg that hatches inside the body in reptiles and sharks).
Noted the two major patterns of cell division in early development: holoblsstic cleavage in which the entire eggs is divided into progressively smaller cells(frogs and mammals)
Meroblastic pattern in which only the part of the egg destined to be an embryo properly divides and the remainder serving nutritive purposes(as in birds)
…….. Described the fetal membrane and umbilical cord in cattle.
Aristotle
Who Observed that embryo’s do develops it organ system gradually. They are not preformed. Denovo formation of embryonic structures, Epigenesis.
Aristotle
Aristotle misconception
That male’s semen didn’t contribute to conception physically
Kopho
Anatomy Porci. One of the first anatomical descriptions of the pregnant uterus of a pig.
Leonardo davinci
Investigated the pregnant uterus of a cow.
Hieronymus fabricus
Italian anatomist
In his book De Formato Foetus described the gross anatomy of embryos and that but wasn’t the first to do so.
Bartolomeo Eustacius
Previous published illustrations of dog and sheep embryos .(Before fabricius)
What is Bursa Fabricius
The immunological competent portion of the hind gut)
Marcello Marphigi
An Italian medical doctor published the first microscopic account of development.
He also examined that unincubated eggs where structured leading him to think that the where preformed
Zacharias Janssen
Developed microscope that could achieve only 10-20 times magnification. It was just to attract audience at country fairs.
Regnier de graaf
Studied female reproductive organs (mainly ovaries) with those of chicken and considered mammalian antral follicles to be the eggs.
Theodor Ludwig Wilhelm
Bishoff
A German medical doctor who introduced tyd nomenclature ‘Graffian follicle”
Karl Er st Von Baer
Opened the “graafian egg”(as the follicle was known) and saw with his eye, a small yellow point and called the mammalian egg
Described the notochord.
Anthony Van leuwen hoek
Reported seeing a moving spermatozoa
Constructed a single lens microscope that magnified 300 times.
Identified 2 mammalian gamates.
Casper federich wolf
Observed the first strong case if epigenesis by demonstrating that gut arises from the folding of an originally indifferent flat tissue.
Christian Pander
Discovered the 3 germ layers
Rathke
Studied comparative embryology in frogs salamanders fish &Bird and looted out the similarities in development a..
Described pharyngeal arches common to the development of these an
Rudolph Albert von kollicker
Along withtheodir Ludwig detailed observations on the initial cleavge stages.
August weismann
Proposed germ cell plasma theory that egg and sperm provided equal chromosomal contributions to the new organism but was wrong about the mechanism of differentiation.
Thanks to ……,…..&….. The preformation school in it’s radical form ceased
Christian Panda,von baer and
MartinHeinrich Ratke
Whelm Roux
Put weismans differentiation theory to test.Destroyed 2-4_ cellfrogs embryo by a hot needle.
Hans Aldof Eduard Driesch
Used cell separation instead of Roux’s cell destruction technique to discover that each if the cells from early cleavage stage were able to develop into a small but complete embryo and larva.
