Mollusks
Mollusks are characterized by having __________ bodies
Soft
Cephalopod means:
Head-foot
Squid have ________ arms
8
Octopus have _______ arms
8
Nautilus have an outer _______ that other cephalopods do not have
Shell
Most mollusks have some form of ___________ (this might be internal or external)
Shell
Most cephalopods have arms that are lined with;
Suckers
Chromatophores are;
Pigment containing cells or groups of cell that produce color
Name 2 ways in which an octopus can move
swimming, crawling, jet propulsion, walking on two “legs”
How does a nautilus swim?
uses jet propulsion
Most mollusks have a tongue like feature called a,
Radula
Give two ways in which cephalopods defend themselves
Camouflage (chromatophores) and change in texture
Ink sac
What is a cuttlebone?
an internal bone of a cuttlefish, filled with air and aids in buoyancy
Other than camouflage and releasing ink, how can an octopus defend itself?
Can remove an arm to confuse predators
Describe the shell of a nautilus
has many closed interior chambers or “compartments”
A form of symmetry in which the opposite sides are similar
Bilateral symmetry
Explain how a cephalopod eats.
Beak-like jaw with a radula tears prey into pieces. Pulls shells apart with suckers and bites open shell with beak
Where are the suckers located on a squid
Arms (all over); tentacles (just on the end - the club)
What do octopus feed on?
Benthic feeders: bivalves, crabs and fish
Describe the tentacles (arms) of a nautilus
up to 90 tentacles with no suckers on them
The function of the mantel in shelled (bivalves) mollusks
To secrete calcium carbonate which is used to form the shell
Explain how cephalopods move
Jet propulsion. Pulls water into mantle cavity and then pushes the water out through their siphon
Name three ways in which a squid and cuttlefish differ
quid have a flexible, feather-shaped structure inside their bodies called the pen, where cuttlefish have a broader internal shell called the cuttlebone
Squid are fast-moving predators, where cuttlefish are slower and move by undulating long fins on the sides of their bodies
Eyes
The largest octopus species
Giant Pacific octopus
Describe how a nautilus controls buoyancy
Pumps water in and out of its shell chambers