Download Mollusks Notes

Phylum Mollusca
General Characteristics:
1. Mollusks contain ___________________ symmetry.
2. The _______________ is a thin membrane used to produce the shell.
3. The three body parts of a mollusk are: the _______________, the
_______________ and the _________________________
(contains the internal organs).
4. Mollusks breathe through their ____________________ or the lining of
the _______________ cavity.
5. Liquid wastes are excreted by one or two _______________.
6. Since the mollusk does not contain many blood vessels they are said to
contain an _______________ circulatory system.
7. Mollusks reproduce ____________________ with the development of the
____________________ larvae.
8. All mollusks are ____________________ and ____________________.
9. They respire through a variety of structures such as: _______________,
_______________, or the _______________.
10. Mollusks possess a centralized ______________ and some have
additional smaller brains called _______________. Several nerve
_______________ extend from the brain.
11. They have sensory organs of ________________, _______________,
_______________, and ________________ (in some); eyes are highly
developed in squid.
12. There are __________ different classes of mollusks.
13. Class _________________________ contains organisms called chitons
that live exclusively in the ocean.
14. Their body contains a shell of __________ plates with a muscular foot,
and a reduced head. These organisms cling to rocks in the
____________________ zone and use a tooth like ____________________
to scrape food off of the rocks.
15. The class ________________________ is the largest molluscan class.
16._______________ and slugs are the most familiar forms in this class.
17. These organisms contain a _______________ shell.
18. This shell has a characteristic cone shape. The oldest part of the shell is
its tip and is called the _______________.
19. They breathe through _______________ or the ____________________
cavity acts as a primitive lung.
20. Their muscular foot extends along the ventral surface of the organism.
Their head contains a pair of ____________________ and a pair of eyes.
21. They contain a scrapping ____________________ to pick up food from
the environment.
22. The ____________________ is a shell-less mollusk.
23. Label the snail below using the following terms: antenna, eyes, muscular
foot, head.
Who is this?
Snail
24. The class _________________________ contains animals covered with
two shells.
25. The _______________ and the _______________ are examples of this
class.
26. These organisms are mainly marine living in the
____________________ zone.
27. The body has a large ____________________ hump and a
____________________ foot with a reduced head.
28. The visceral hump and foot are covered by a thin
____________________.
29. The mantle produces a cavity where the gills and 2 siphons ( the
____________________ and incurrent siphons) are found.
30. These animals are _______________ feeders. They take water
containing food into the mantle cavity and pass over in the mouth. The
excess water is forced out through the ____________________ siphon.
31. The shell contains ________ layers: the outer ______________ layer,
inner __________________ layer, and the inner ________________ layer.
The _______________ is the oldest section of the shell.
32. Label the picture below using the following parts: foot, umbo, and shell.
Bivalve (Clam)
33. The class_________________________ contains the squids, octopuses,
cuttlefish, and nautiluses.
34. All members of this class are_________________________.
35. Squid and octopi and among some of the most intelligent of the
____________________.
36. All cephalopods are carnivorous. They contain ____________________
and a central mouth containing a sharp beak. Many of these organisms
contain a large ____________________ that is used when trying to escape
from potential predators.
37. They have well developed eyes and brains. They have
_________________________ in the mantle cavity. They possess a
______________ circulatory system.
Colossal Squid
Cuttlefish