Cephlapoda

Question 1

How do mollusc shells form?

Answer 1

Secretion of mantle fluid from the mantle tissue, attracts carbonates.

Question 2

Which mollusc trend do cephalopods and gastropods belong to?

Answer 2

Cyrtosoma
- single valved
- well developed head and sensory organs

Question 3

Characteristics of Class Cephlapoda.

Answer 3

a. Foot split into tentacles
b. formation of beak, retention of radula
c. well developed sensory system, including eyes
d. incredibly intelligent
e. hyponome developed for jet propulsion

Question 4

Features of shells.

Answer 4

a. Typically only spirals in one plane
b. separated into chambers (septa)
c. distinctive suture patterns produced.
d. siphuncle which moves fluid and gasses between chambers
e. phragmocone includes previous living chambers.
f. body chamber - where current mass lives.

Question 5

What do heteromorphs indicate?

Answer 5

Rapid growth. Evidenced by a lack of growth lines and lack of intermediate individuals in fossil record.