May 31, 2007
The skin starts to "dissolve" when starfish
have undergone stress. This is an early stage, where the guts and ovary are
just beginning to come through, but it's basically hopeless once it starts.
This starfish was dissected.
1 - ovary visible in a triangle cut between the
arms
2 - higher mag, also showing cross section of "skin" in this region
3 - showing the relationship of ovary to guts - ovary is on the underside
= "ventral"
4 - shows ovary in the region between the two arms
5 - this shows the place where the ovary connects to the gonopores - there
are two stubs here in the region between the two arms. Also note the appearance
of the guts once the overlying ovary has been removed.
6 - shows what is underneath the guts: just skin (lower
right)
7 - central part cut out - view from underside
8 - the underside of the central part cut loose; mainly the guts connected to
the mouth. This may be the part that gets extruded from the mouth when the starfish
is eating.
9 - interior view of the top of the central part, after connection to the interior
parts were removed. Forceps point to the location of the gonopore
10 - sideview of the underside of the central part
11 - mouth (outside view) and guts after cutting loose from the mouth
12 - interior view of mouth region
13 - two large pieces of ovary, separated at the gonopore connection so they
are essentially whole pieces
14 - two pieces of gut that were extending into the arm.
15 - 16 - 17 - higher magnification views of gut