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SQUID DISSECTION. Position your squid. Place squid in tray, with its dorsal side facing up. Pigment Cells (chromatophores). Peel off a thin, spotted piece of skin. Place on a slide & observe under the microscope.
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Position your squid • Place squid in tray, with its dorsal side facing up.
Pigment Cells (chromatophores) • Peel off a thin, spotted piece of skin. • Place on a slide & observe under the microscope. • (By stretching and contracting these pigment cells, a squid can change color!)
Tentacles & Arms Notice the difference between arms and tentacles. Observe the suction cups.
Beak • Spread the arms apart to find the beak. • Use tweezers to remove the beak. • Move the beak to see how it works!
Eye • Compared to other animals, are the squid’s eyes large or small for its body size? • What does that tell us about where the squid lives?
Pen • Using both hands, hold your squid by the head and the tail. Wiggle it to see how stiff it is. (Some squid relatives still have their shells….) • Now, remove the pen as indicated. <-- It’s clear and stiff
Siphon • Locate the tube-shaped muscle just below the head, on the ventral side. This is the siphon. It works using JET PROPULSION, and is a little like a water hose.
CUTTING IT OPEN • Place the squid ventral side up & cut up through the mantle.
Reproductive Systems • FEMALE: You will see a yellow, jelly-like mass that looks like Vaseline. This is the substance that holds the eggs. • MALE: The male genital duct is a small, white, fluid-filled sac in the posterior end of the mantle. The sperm are stored in thin tubes in an elongated sac behind and along one gill.
Gills • Find the gills. These are the long, feather-shaped organs that are attached to the sides of the mantle and extend along the anterior half of the mantle.
Heart • When the gills are straightened, they make a “V” shape. At the point of the “V” shape is a small lump. This is the squid’s heart. • It is very hard to locate.
Digestive System • The long, silvery dark tube on the bottom of the liver is the ink sac. Be careful not to break it open. • Locate the stomach and caecum - one white, silky-looking tube, like a deflated bladder and a coiled sack. • The bunched up organs that look like human intestines are digestive ducts for the squid. • If possible, open the stomach and examine its contents. Many squid will have bits of partially digested crustaceans (pink and white pieces), or tiny fish scales and bones.
And finally, the Ink Sac • Gently cut the ink sac from the organs where it is attached. • CAREFUL: Squid ink stains clothes. What is this ink used for? Alright kiddies… you can write with it.