Which specific cellular mechanism in cnidarians allows for the rapid discharge of nematocysts, considering the internal osmotic pressure is significantly higher than the surrounding seawater?
Passive diffusion of water into the cnidocyte, increasing internal pressure
Active transport of sodium ions out of the cnidocyte, creating an osmotic gradient
Rapid influx of calcium ions triggering forceful contraction of surrounding myoneme cells
Enzymatic breakdown of the cnidocil cap, releasing stored elastic energy
Related Questions
Which of the following is not found in Hydra?
Epithelio-muscular cells
Cnidocyte
Choanocyte
Nerve cells
Which of the following statements are true?
Phylum-Porifera-Presence of choanocytes and nematocysts
Phylum-Coelentrata-Meandrina belongs to this phylum
Phylum-Ctenophora-All exhibit bilateral symmetry
Phylum-Platyhelminthes-Wuchereria belongs to this phylum
In the life cycle of Obelia, which phenomenon is observed?
Binary fission
Budding
Metagenesis
Fragmentation
Which cnidarian class includes organisms that exist predominantly in the polyp form?
Hydrozoa
Scyphozoa
Cubozoa
Anthozoa
Which of the following is not true regarding phylum-Coelenterata?
They are diploblastic.
They have a complete digestive system.
They have cnidocytes.
They exhibit radial symmetry.
Find the odd example.
Sea lily
Sea fan
Sea cucumber
Sea urchin
Alteration of generation is also called
Metamorphosis
Metastasis
Metazoan
Metagenesis
The main nitrogenous waste of Hydra, is
Ammonia only
Urea only
Uric acid only
Both (a) and ©
Regeneration in Hydra will be faster, if it is cut off from
Head region
Mid-body region
Basal disc
Tentacles
Characteristic cells of Hydra are
Archaeocytes
Thesocytes
Cnidoblasts
Trophocytes
