Here’s Looking at You, Squid!Name
Squid Lab: artwork, dissections, and calamari!Period
In Jules Verne’s classic novel, 20,000 Leagues Under The Sea, the heroes battle a deadly giant squid that threatens to crush the hull of a submarine called the ‘Nautilus.’ Although giant squids do exist, most of us have only encountered their smaller, more timid relatives. Yet even the smaller squid looks like the stuff of science fiction. The top of the squid’s head is actually a combined body-tail unit called the mantle. The head has two large eyes and is surrounded by two long tentacles and eight arms with rows of round suckers underneath. Underneath the head is a small opening to the funnel. The squid forces a jet of water through the funnel/siphon to propel itself backward or forward. Two fins are attached to the tail end of the squid to help it steer. Although the squid doesn’t have a backbone, it does have a hard internal structure called a pen. Now you can take a closer look at the unusual features of a squid, an aquatic invertebrate.
Objective: To identify a number of organs and their functions of the squid’s anatomy. Remember that structure and function are complementary-that is, the shape of a organ gives you a hint about what job it does.
Part I (20 minutes) External Anatomy Observation
- Lay out newspaper on your table. Put on a pair of gloves. Obtain a squid and lay it out on the paper. Spread the arms apart and make sure the fin (dorsal side) is down.
- Use the white laminated lab diagrams to help you identify the external parts of the squid.
- Visually inspect your squid and identify and label the following parts on the diagram on the next page: Mantle 8 short arms Beak (inside the tentacles)
Eyes Fins2 long tentaclesFunnel (siphon) opening
- Observe the animal’s skin. What is its appearance? ______
Look at one of the spots with a magnifier. What do you notice? ______
These spots are called chromatophores and enable the animal to change color. What colors do you think this animal could change into? ______Why do you think this animal
might need to change color? ______
- Examine the tentacles and arms. How many arms and tentacles does the animal have?
Arms =______Tentacles = _____
Did you notice that two are longer than the others. These are the tentacles. What do you guess is their special purpose? ______
Look at your white lab diagram to see a drawing of a tentacle. What do you think is the purpose of
the suckers? ______
Use a magnifier and draw one of the suckers enlarged in the box to the right:
6. Spread the tentacles apart, in the center is the black beak. Use a probe to open the beak. How many parts does the beak have? ______
7. Now look at the eyes. From their position, in what directions do you think the squid can see? ______
Dissect an eye. Find and remove the hard lens from one of the eyes, Be careful they squirt! Put the eye on the template sheet.
Part II (20 minutes) Squid Art
You are going to do a Gyotaku, that means ‘fish rubbing’ in Japanese. Fish printing originated in Japan or China in the early 1800’s. In Japan, Gyotaku is practiced by sportsman to preserve records of their catch. Practicing this art is a good way to gain appreciation of the beauty and variety of marine organisms. This technique is effective for making prints of fish, shells, rocks,
flowers, and other natural objects.
- Make sure your squid is lying flat with the fin side up. Make sure the squid is dry and clean.
- Obtain the white paper, paint, and brush from your teacher.
- Brush a thin coat of paint on the squid. Leaving the eyes unpainted. Make sure it has a good coat of paint but not sloppy (excessive) in order to get a good print.
- Carefully place paper over the squid. Press down gently with your fingers over the entire painted squid. Be careful not to wrinkle or move the paper too much.
- Rub the entire squid and then lightly remove the paper.
- With a small brush paint in the eyes. Write your name and period on your print and turn it in.
- Clean your brushes and return them and the paint to your teacher. (back table).
- Put your squid on the paper with the fin (dorsal) side down for the next part: the dissection. You don’t need to wash it off.
Part III (35 minutes) Internal Anatomy Dissection
- Make sure the funnel (siphon) side is up and fins side down. Using the scissors cut from the
lower edge of the mantle (collar) to the cone-shaped tip of the mantle. Use your fingers or forceps to hold the mantle as you cut.
- Lay open the mantle as shown on the white lab diagram.
- Locate and label on your worksheet the following structures:
mantle collar fins eyes funnel (siphon) gills
ink sacanusstomachlivergonad (sex organ)hearts (3)
- Squids are molluscs. They have a soft body and a hard shell. However their soft foot is divided into many arms and their shell is long, slender, and called the ‘pen.’ Locate the pen on the underside of mantle and grab its tip on the lower edge (collar)of the mantle and pull it out. It takes some effort. Wipe the pen dry and try not to bend it much. You can have it!!
5. Find the dark silvery ink sac and remove it. Break it open with a probe and then see if you can
write whatever you want in the square below (use the ‘pen’ if you want):
Feel free to check out all the parts that interest you and ask questions!!
6. Clean up time! Please throw your squid, and newspaper away but return the probe and scissors to the tray on your table. Also keep the white laminated lab diagrams on the table. Remember to turn this lab in before you go.