Chapter 16: Phylum Mollusca, Class - Cephalopoda

Question 1

What organisms are included in this? (4)

Answer 1

• squids
• octopuses
• nautiluses
• cuttlefish

Question 2

All organisms in this class live in \_\_ environments and are \_\_\_ predators. 
- A modified foot is concentrated in the \_\_ region.

Answer 2

• marine
• active
• head

Question 3

The shell is reduced in ___(pen) and disappeared entirely in the ___.
They swim by forcefully expelling water from the ______ through a ventral funnel aka ___.

Answer 3

• squids
• octopuses
• mantle cavity
• siphon

Question 4

• They all have a ___ circulatory system as they are more active.
• The nervous system is ___ developed.
• They have the largest invertebrate __.
• What organisms have the largest axons in the animal kingdom and belong to this group?
• They have very complex ___, ___ are always in horizontal position.

Answer 4

• closed
• highly
• brain
• squids
• eyes, pupils

Question 5

• Most can see in colour or are they colourblind?

- They are capable of what two unique things?

Answer 5

• colourblind

- learning and observational learning

Question 6

How do they communicate? (2)

Answer 6

• body movements

- colour changes in skin due to chromatophores

Question 7

What do bright colours indicate ?

Answer 7

warning signs

Question 8

• The sexes are ____. Spermatozoa are encased in ____ and stored in mantle cavity in sacs.
• In males what does the modified arm function as?
• Eggs are fertilized when they leave what?
• What animals in cephalopoda tend to their eggs?

Answer 8

• separate
• spermatophores
• plucks sac and inserts into mantle cavity of female
• oviduct
• Octopus

Question 9

• Eggs undergo ___ cleavage
• Most usually ___ soon after mating or the eggs are laid
• Some species of ___ may live for a few years.

Answer 9

• meroblastic
• die
• squid