Sub-topic #1: Basic Parts

• Cnidocil

  • trigger structure that is sensitive to mechanical stimuli and chemical stimuli such as amino acid
• Shaft

  • morphology is an important taxonomic character depending on its thickness
• Stiletto

  • long spines which control the eversion of organelle
  • if not needed, it is inside only
• Non-everted Stage

  • thread is coiled inside the capsule
• Spines

  • also an important taxonomic character
• The release of nematocysts all takes place within 3 milliseconds and is among the fastest processes exhibited by living organisms.
• Identify parts:

  A) thread

  B) spines

  C) stiletto

  D) shaft

  E) capsule body

  F) lid