Bio Starfish Lab

Problem:
What are the internal and outdoor(a) structures of a sea star?

Hypothesis:
I will examine the external and internal characteristics of a sea star. Since they are members of the phylum Echinodermata, they may discombobulate tough outmost surfaces with spines. Their internal systems may consists of a sing, stomach, digestive glands, and an anus.

Materials:
- preserved sea star - plastic gloves - dissecting pan
- scalpel - dissecting scissors - dissecting probe
- lab apron - eye goggles

Procedures:
Part A:
1. Work with a partner. Wear your safety goggles, lab apron, and plastic gloves. Place the
sea star in the dissecting pan with its dorsal array up. keep on the number of rays the
sea star has. Observe the spines.
2. Find the madreporite on the dorsal surface. It is located in the fundamental disc, the area to
which the weapons system are attached.
3. Turn oer the sea star so that the ventral side is side up. Observe the ambulacral
grooves that run the distance of each ray. Locate the tube feet covering the grooves.
Observe the mouth in the central disc.
4. In the spaces provided, draw the dorsal and ventral views of your sea star. Label the
external parts that you observe.



On some other sheet or paper, record any other
observations you take hold round the external characteristics of your sea star.

Part B:
1. Turn over the sea star again so that the dorsal side is up, and again locate the
madreporite.
2. Carefully cut a jog around the madreporite. Then cut mutilate the tip off the end of an
arm that is opposite the madreporite.
3. From the cut tip of the arm, tho on the dorsal side of the sea star toward the
madreporite and central disc. Using the dissecting probe, remove the outer(a) surface of
the arm and the outer surface on the central disc. Do not make deep cuts into the sea
stars internal tissues. Beneath the outer skin/skeleton are the sea stars internal organs.
4. In...If you want to get a full essay, lay it on our website: Ordercustompaper.com



If you want to get a full essay, wisit our page: write my paper