Squid Dissection

On friday, I was kind of surprised to find that my class was dissecting a squid, mostly because I kind of forgot. Nevertheless, it was awesome to dissect something larger than an earthworm! To start off, we were to go with our partners and get supplies consisting of Scissors, forceps and other items that would all help with the procedure. Before anything, I went to the front of the class, where some sheets were set up so I could do a small pre-lab activity of naming certain body parts of a squid. Then, my teacher opened up a container full of squids, which may I say, did not smell too good. But once I received a single squid, the smell was unnoticeable, and my partner and I were able to get to work. Our objective was to find and observe the exterior parts of the squid, and then after careful cutting, view the internal organs of the squid. During all of this we were to locate the body parts that perform functions, and then analyze how those functions would be performed. By making these connections, the brain can have a better and easier time remembering and retaining the knowledge learned. You can learn more by first hand cutting than by reading large paragraphs. For example, one could look at the beak and see how it opens and closes, and also find where the food comes and goes, and by doing that observing learn more than reading 5-6 sentences on the subject.
To begin the dissection, we first had to look at all the external parts of the squid, like the tentacles and arms. Just seeing these was awesome, because they looked like how I'd always seen them in movies and t.v; were long and had suckers, although, only some had suckers. After careful observation of the exterior, we began to cut. Some groups were too hasty and directly went to cut up the squid, which took away from the first few steps on the hand-out we were given. Aside from this, my partner and I made a good, clean cut, and carefully spread apart the squid to see it's insides. Unlike the earthworm, we didn't have guts fall out or soil. In fact, everything seemed to stay in place, which was good. We then carefully observed it's insides and what parts were which. Some if it kind of looked like an egg to me, but the thought didn't last very long considering I could see a whole bunch of other things as well. All in all, this was a great and fun learning experience, and I hope to do something similar again in class!

1.) How many arms does your squid have? How many tentacles?
The squid I had dissected had 8 arms, and only 2 tentacles with suckers. This picture isn't very good, but it does have all the feet shown.

2.) Based on the structure of the arms and tentacles, describe how their purposes differ. What do the arms do and what do the tentacles do?
This is a close up of the suckers of a squid, located on the tentacle. The tentacle is better for grabbing prey that swims by, and holding onto them, as well as latching onto surfaces like rocks. (Look below for Arms)

This is a close up of just a regular arm of a squid. The arms are much better for the locomotion of the squid, for they are shorter and can move quicker.

3.) Draw arrows on the squid (above) to indicate the direction that water comes out of the funnel and the direction that the squid moves

4.) Name two external features that are adaptations for the squids predatory life. How do these adaptations help the squid?
One of these adaptations, is the suckers on the tentacles. These suckers attach onto prey and hold them down from escaping. This leads to the 2nd adaptation, which is the beak. The beak can pick apart prey, making it easier for digestion. Since there is already a picture of the suckers up above, I only used this close up of the beak.

5.) Do you remember the general traits of mollusks we discussed in the lecture? Name two traits that the squid shares with other mollusks.
A.) The visceral mass is the soft bodied portion of mollusks that contains the internal organs, and in this case, is the mantle of the squid (shown above).
B.) Feet are also found in all mollusks, and in this case, are the arms and tentacles of the squid. (Shown Below)

1.) How many pairs of gills does the squid have?
The squid that my partner and I dissected had 2 pairs of gills

2.) Where does the ink sac empty into and what is it's function?
The ink sac (shown above) empties into/ out of the funnel, and the ink itself serves as a distraction to help get away from predators. The funnel works to dispel the ink and propel the squid forward.

3.) What is the function of the pen? What would happen if the squid didn't have the pen?
The pen serves as structural support for the squid, holding the organs together and stabilizing the squids body. Without it, the squid itself would be a floppy mess. The pen is shown above and below.

4.) How do you think wastes exit the squid?
I believe that larger, more solid wastes exit through the anus, and smaller wastes exit through the funnel (shown above).