[1] Mollusca Intro

• In the larger clade of Lophotrochozoa, Mollusca are under the subclade Trochozoa

  • This means they have Trochophore larva
• 2 main parts of the molluscan body plan

  Head-foot and visceral mass
• The soft parts of the mollusc are covered by a protective tissue secreting the shell, called the mantle
• Space between the mantle and the body

  Mantle cavity
• Ribbon of tissue that contains the teeth, specific to molluscs

  Radula
• 3 layers of the shell

  1. Periostracum
  2. Prismatic
  3. Nacreous
• Outermost layer of the shell

  Periostracum
• Middle layer of the shell

  Prismatic layer
• Innermost layer of the shell

  Nacreous layer
• Match shell layer with component:

  • Periostracum - Conchiolin
  • Prismatic - Calcium carbonate + protein
  • Nacreous - Calcium carbonate
• Other name for trochophore larvae

  Veliger