Squid Dissection

Purpose and Goals:

The squid dissection on Friday was an exciting, slimy, and slightly displeasing to the nose (and also a delicious one?). The purpose of said dissection was to fully understand and explore the internal anatomy of a real, (once)-living squid. Some goals I set for myself during the course of the dissection were: to locate and examine the body structures, to relate physical (internal and external) features and characteristics to classroom and textbook material, and to appreciate and gain a deeper understanding/perspective of some simple things in life, such as this simple (delicious) squid. Also, an often excluded and hidden purpose in every dissection, and especially in this one, is to enjoy ourselves. During this dissection, I met (and exceeded?) all of these goals.

Understanding of the biological world:

              

This dissection not only opened my eyes to the details and complexity of some of the simple things we find in everyday life, but also showed me the deeply intricate interactions between these mollusks and the     biological world. The dissection allowed me to see how the squids capture prey, protect themselves, and how they move through their environment from the different structures the squid developed and enhanced over many many generations. These simple, yet exceptionally efficient structure show me the occupation of different niches by the squid, showing me how these organisms interact and contribute to their surrounding environment.

Relation to Class Material:

How is dissecting a squid related to a chapter on squids (mollusks)? Well, for one, they are both about squid. But more importantly, information from actually seeing the squid intertwine with the information in the textbook, such as the features and characteristics, and also the general relation to other mollusks, such as having a coelom and possessing a one-way digestive tract. From the dissection, parts and organs are clearly shown, forming a mental picture of why each part of the squid is there and its function and use. For example, I learned that squid have gills to perform respiration, but have never considered how, but seeing the gills on the sides of the squid's internal organs, I could visualize that the squid could draw in water and bring in O2 from the gills. 

Personal Response:

I found this dissection to be interesting, exciting, and quite amusing. I enjoyed poking pins on the squid and probing around its organs, and feeling how slimy they are. I took note of the body structure of the squid and it fascinated me to realize that these squid could, in fact, squish and squeeze themselves into just about any space possible! I also quite enjoyed playing around with the little guy... poor guy, he didn't deserve to die in the hands of... us. Anyway, the dissection proved again to be a easy to follow step-by-step teamwork project, and it helped me learn and explore not only the inside of a squid, but also the general shape and characteristics of mollusks, and allowed me to glance (even if just a little), in to the entire massive kingdom of animals.

External Anatomy

1. How many arms does your squid have? How many tentacles?
A: The squid has eight arms and two tentacles.


2. Based on the structure of the arms and the tentacles, describe how their differ. What do the arms do and what do the tentacles do?

A: The tentacles are used to capture prey due to their length and the arms are short with suckers which can be specialized for sexual reproduction (production of gametes), used for locomotion, and pushing the prey into its mouth.

3. Draw arrows on the squid to indicate the direction that waters comes out of the funnel and the direction that the squid moves

4. Name two external features that are adaptations for the squid's predatory life. How do these adaptations help the squid?

A: -Suckers on the squids arms help it grab on to any prey and prevent it from escaping

     -The well developed eyes on the squid allow it to seek out its prey and find it before it escapes

5. Do you remember the general traits of mollusks we discussed in lecture? Name two traits that the squid shares with other mollusks.

a. The squid exhibits bilateral symmetry, similar to all other mollusks. This shows the development from simple to more complex organisms.

b. The squid has gills, which are used to breath, like all other mollusks. O2 is extracted through these gills in the process of gas exchange.

Internal Anatomy:

1. The squid has one pair of gills, on on each side of its organs.

2. The ink sac empties through the pen and into the siphon, and sprays predators in time of danger,

3. The function of the pen is to draw the ink out from the ink sac for it to be released into the water. Without the pen, the flow of ink would be uncontrolled (too much) and the ink may spill into the internal cavity or may not be able to shoot the ink out with pressure.

4. Wastes exit the squid from its anus, located above the internal organs, attached to the intestines (solid waste). The nephridia filters the blood of the squid and releases waste also.

Pictures on iPad #3 in album named "Squid dissection Nick"