Time to Open Up Squidward

Squid Dissection

In this class, we performed another dissection. Instead of dissecting a small earthworm, we got to dissect a squid! This time around, it was much easier to perform a dissection on this mollusk because it was much bigger. The purpose of this dissection was to again incorporate that visual aspect to our learning in Biology 11. A goal was to open this squid up and answer the questions on the lab to further extend our knowledge of a Cephalopod, also known as "head" "foot". With this dissection, we got to discover the flow of the water through the funnel and how it moves by jet propulsion. Also, using a microscope, we got to see the little pods of colour on the squid's skin that enables it to camouflage to it's surroundings. These were some of the many findings we discovered during this dissection. These help us understand not only how squid work, but also how we can save them. I enjoy dissecting animals because I love hands on work. It helps me learn about the animal we are discussing in class.

Questions: 

External Anatomy Questions

How many arms does your squid have? How many tentacles?

Squids have eight flexible tentacles and two long slender arms  with suckers on the end.

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

The purposes for the arms is to grab prey. The function for the tentacles are for pulling the prey to the beak for consumption. The two differ because the arms acts as more of a tool to attack and tentacles are used for help in feeding.

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

The water flows as shown on this picture. Also, the movement of the squid due to jet propulsion is shown.

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

1. The suckers on the tentacles and the tentacles 

and arms themselves are used to grab prey and making

 it almost impossible to escape.

http://www.youtube.com/watch?v=X2aa6aHEyUI












2. The beak also serves as a serves as a tool for the squid's predatory life. The sharp talon looking beak is great for ripping apart the food for digestion.

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

1. They both have a mantle. 

2. They also both have a visceral mass. 

As well, they all share bilateral symmetry and a soft body cavity. (coelom) 

Internal Anatomy Questions

How many pairs pf gills does the squid have?

The squid has two gills therefore the squid has one pair located near the stomach.

Magnified

Where does the ink sac empty into and what is it's function?

The ink sac empties into the water jet and it is used for defense by distracting the predators.

http://www.youtube.com/watch?v=O0iqRah3N0I

What is the function of the pen? What would happen if the squid didn't have a pen?

It provides stability for the squid so it could swim. Without it, the squid wouldn't have any structure and have many difficulties swimming. 

How do you think wastes exit the squid?

Waste exits the squid through the anus then the water jet where the waste is finally expelled into the water.