Mollusks Read and Color

Mollusks Read And Color

The mollusks are members of the large and diverse phylum Mollusca, which includes a variety of familiar animals well-known for their decorative shells or as seafood. These range from tiny snails, clams, and abalone to larger organisms such as squid, cuttlefish, chambered nautilus, and the octopus (the most intelligent mollusk). The vast majority of mollusks live in marine environments, mainly on the coastal plains. However, two groups, the bivalves and the gastropods, also contain freshwater species, and only the gastropods have representatives that live on land (snails and slugs).

Chitons

Chitons are mollusks that along ocean coastlines in most of the world, but some species have been found in deep water. They creep along slowly on their muscular feet and cling to rocks. Chitons have shells made up of overlapping plates. The shell is divided into eight plates embedded in the tough muscular girdle that surrounds the chiton's body. Label and color the girdle tan and the plates dark green. This arrangement allows chitons to roll into a protective ball when dislodged and to cling tightly to even irregular surfaces.

Chambered Nautilus

The Chambered Nautilus is the best known species of nautilus. The spiral shaped shell, when cut away, reveals a lining of shiny mother-of-pearl. The nautilus has primitive eyes compared to other cephalopods, mostly due to the fact that they have no lens. It has about 90 tentacles and NO suckers which is also different from other cephalopods. This nocturnal animal has a pair of rhinophores, which detect chemicals and uses smell to find its food. Color the shell sections of the nautilus tan and brown.

Cephalopod Mollusks Octopus

The word octopus means "eight feet." Octopi (plural form) are solitary animals with arms or tentacles that have suckers. They live on the ocean floor. There are over 100 different species of octopus. The Giant Octopus is the biggest octopus. This huge mollusk is up to 23 ft (7 m) from arm tip to arm tip, weighing up to 400 pounds (182 kg). The smallest is the Californian octopus, which is only 3/8 inch (1 cm) long. An octopus has a soft body (visceral mass) and eight arms. The soft body is covered by a protective layer called the mantle. Label and color the head and mantle dark blue. Each arm has two rows of suction cups. If it loses an arm, it will eventually regrow (regenerate) another arm. Label and color the arms gray and the suckers pink. It has blue blood. An octopus has an eye on each side of its head and has very good eyesight. Label and color the eye yellow. An octopus cannot hear. Octopi eat small crabs and scallops, plus some snails, fish, turtles, crustaceans (like shrimp), and other octopi. They catch prey with their arms; kill it by biting it with their tough beak, paralyzing the prey with a nerve

1 poison, and softening the flesh. Color and label the beak red. They then suck out the flesh. Octopi hunt mostly at night. Only the Australian Blue-ringed octopus has a poison strong enough to kill a person. Octopi live in dens, spaces under rocks, crevices on the sea floor, or holes they dig under large rocks. Octopi pile rocks to block the front of their den. The den protects them from predators (like moray eels) and provides a place to lay eggs and care for them (a mother octopus doesn't eat during the entire 1 to 2 months she is caring for her eggs). In order to escape predators, an octopus can squirt black ink into the water, allowing the octopus to escape. Another defense that octopi have is changing their skin color to blend into the background, camouflaging them. The octopus swims by spewing water from its body through a siphon, a type of jet propulsion.

Read the definitions and the color and label the squid diagram below: Arms - eight short limbs, each of which has Feeding tentacles - the two, long tentacles two rows of suction cups on the lower side; are used for obtaining prey; they have the arms hold the food while the squid bites toothed suckers only near the tip it into swallowable pieces Beak and mouth - the parrot-like beak on Head - the small part of the body between the mouth is used for biting food into small the mantle and the arms; the head contains pieces. The beak and mouth are surrounded the eyes, the brain, and the muscular buccal by the bases of the arms and tentacles mass, which crushes the food Clubs - the ends of the tentacles, which Mantle - the large part of the squid in front have toothed suckers of the head; inside the mantle are the stomach, gills, ink sac, pen, reproductive organs, and many digestive organs Eye - an organ used to see; squids have two, Siphon - a tube-like organ on the lower side very large eyes; they are large in proportion of the head; it expels water forcefully, to the size of the body enabling the squid to propel itself through the sea Fins - two flaps on the mantle that are used to stabilize the squid during swimming

Gastropod Mollusk Read the definitions and the color and label the land snail diagram below: eyespots - located at the tips of the mouth - on the underside of the head - it contains long tentacles on land snails (red) the radula, a file-like tongue that breaks down the snail's food foot - the soft, muscular part of the snail that allows movement (tan) respiratory pore - a small hole in the side of the body, used for breathing (green) shell - the hard, spiral, protective covering of the snail (brown) tentacles - two long and two short sensory tentacles on the upper surface of the snail's head head - the front part of the snail, (Purple) containing the tentacles, eyes, and

2 mouth (gray)

Bivalve Mollusk Clams are animals that burrow under the sea floor. They are bivalves, mollusks that have two shells that protect a soft body. The oldest and highest part of the clam shell is called the umbo. Label the shell and the umbo. The clam's shell is laid down in rings. The rings close to the furthest from the umbo are the newest. Label and color the rings red- brown. The biggest clam is the Giant Clam is up to 4.8 feet (1.5 m) long and weighs up to 550 pounds (250 kg). Most clams are only a few inches long. Clams come in many colors, including shades of brown, red-brown, yellow, cream, etc. The two shells are attached by a muscular hinge and open and close with the help of an adductor muscle. Label and color the muscular hinge orange. When a clam is threatened, most clams will pull their soft body into the shells and close the shells tightly for protection. The foot is used to burrow into the sand. The foot can be extended outside the shells or valves. Color and label the foot light blue. Clams use their tube-like siphon to draw in water, from which they extract oxygen and filter plankton (tiny plants that they eat.) Clams have both an incurrent and excurrent siphon for water to enter and leave. Label and color the siphons pink. The neck and soft body are at the base of the siphons. Label the neck and soft body.

Questions: Answer on Binder Paper and Attach to your coloring WS. – Use your textbook, including the Table on Pg. 334, to help.

1. Define visceral mass and tell what protects it. 2. How do aquatic mollusks breathe? 3. What structure does the foot become in Cephalopods? 4. What is a radula and how does it work? 5. Name 5 mollusks with a shell. 6. Name 4 mollusks without a shell. 7. How does a chiton protect itself? 8. How does the chambered nautilus find its food? 9. What opens and closes bivalve shells? 10. How can you determine the age of a bivalve? 11. How do bivalves feed? 12. Give 2 defense mechanisms used by octopi. 13. What extremes does a mother octopus go through for her young? 14. How do squid and octopus move quickly away from predators? 15. What senses does an octopus have? What does it not have? 16. Explain what a trochophore and veliger are. How are they similar and different? 17. How do cephalopods communicate? How are chromatophores involved? 18. Explain the circulatory system of mollusks.