Embryo (fwd)

[Katica Ilic]

Hi All,

The message below is the e-mail from Teresa Tykarska (published a
series of papers on Brassica embryogenesis, 1979-1987) who I
contacted last summer asking about the embryo proper, definition and developmental
connotation of this term. I got her reply just before aspb meeting in
Florida  and didn't forward it to po-dev.

Peter may recall this, last June in St Louis, we were  not sure about
definition, and also whether to use an instance_of or part_of relationship
to the parent term 'embryo'.

Katica

---------- Forwarded message ----------
Date: Thu, 15 Jul 2004 23:52:48 +0200 (CEST)
From: Leonard Tykarski <tykarski at olimp.if.pw.edu.pl>
To: katica at acoma.Stanford.EDU
Subject: Embryo

Dear Dr Ilic,

As I wrote you before, I.m sending you my comments, that you ask me for.
Till now on there is no unified terminology regarding embryo and such work
would be very useful.
My opinion is mainly based on the best source, i.e. the work of Hanstein
(1870):
1.	Embryo development is divided into the period of proembryo and the
period of embryo proper (globular, heart-shaped, torpedo,.........,
maturing and mature stages).
2.	Transition of the proembryo to the embryo proper occurs at the
moment of initiation of the basic parts of axis of the future plant, i.e.:
plerome mother cells (axial cylinder) and periblem mother cells (primary
cortex).
3.	Hypophysis is the highest cell of the suspensor. It joins the body
of embryo during its first division, closing the embryo sphere (globe)
from the bottom.
Hainstein named .embryo sphere. also as .the embryobody., which I used in
my work. Some researchers when referring to the .embryo proper. think of
the embryo body.

I.m not sure if these explanations are sufficient to you. I will be out of
Warsaw for a week. If you would have any questions, please use the
address, which I use at home (it.s my husband.s address):

tykarski at if.pw.edu.pl

Best regards,
Teresa Tykarska