difference/s: Hydras live in fresh water environments, while sea anemones live in marine environments. Hydra, although primarily sessile (sedentary), may move up to several inches in a day.
similarities/s: both are part of the phylum cnidaria, have radial symmetry, a gastrovascualr cavity, an incomplete digestive system (only one opening, considered their mouth), a mouth surrounded by tentacles, and both are sessile polyps.
The trigger mechanism of the nematocyst organelle of the stinging cnidocyte cell consists of a sensory hair and a chemical receptor. When the sensory hair is mechanically stimulated, it activates the chemical receptor, leading to the discharge of the nematocyst's venomous contents.
A cnidocyte, cnidoblast, or nematocyte is a type of venomous cell unique to the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). The cnidocyte cell provides a means for them to catch prey and defend themselves from predators. A cnidocyte fires a structure that contains the toxin, from a characteristic sub-cellular organelle called a cnidocyst (also known as a cnida or nematocyst). This is responsible for the stings delivered by jellyfish.
When a stinging cell, also known as a cnidocyte, comes into contact with another organism, it triggers the discharge of a harpoon-like structure called a nematocyst. The nematocyst injects venom into the target, immobilizing or deterring it. This process is crucial for capturing prey or defending against predators in cnidarians such as jellyfish and sea anemones.
s a type of venomous cell unique to the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). The cnidocyte cell provides a means for them to catch prey and defend themselves from predators. Despite being morphologically simple lacking a skeleton and usually being sessile, cnidarians prey on fish and crustaceans. A cnidocyte fires a structure that contains the toxin, from a characteristic sub-cellular organelle called a cnidocyst (also known as a cnida or nematocyst). This is responsible for the stings delivered by jellyfish. s a type of venomous cell unique to the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). The cnidocyte cell provides a means for them to catch prey and defend themselves from predators. Despite being morphologically simple lacking a skeleton and usually being sessile, cnidarians prey on fish and crustaceans. A cnidocyte fires a structure that contains the toxin, from a characteristic sub-cellular organelle called a cnidocyst (also known as a cnida or nematocyst). This is responsible for the stings delivered by jellyfish.
Cnidocytes are specialized cells found in cnidarians (such as jellyfish and sea anemones) that contain stinging organelles called nematocysts. The function of a cnidocyte cell is to capture prey or defend against predators by discharging venom-filled nematocysts in response to touch or chemical stimuli.
nematocyst
nematocyst
The trigger mechanism of the nematocyst organelle of the stinging cnidocyte cell consists of a sensory hair and a chemical receptor. When the sensory hair is mechanically stimulated, it activates the chemical receptor, leading to the discharge of the nematocyst's venomous contents.
A cnidocyte, cnidoblast, or nematocyte is a type of venomous cell unique to the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). The cnidocyte cell provides a means for them to catch prey and defend themselves from predators. A cnidocyte fires a structure that contains the toxin, from a characteristic sub-cellular organelle called a cnidocyst (also known as a cnida or nematocyst). This is responsible for the stings delivered by jellyfish.
A cnidocyte is a specialized stinging cell found in cnidarians such as jellyfish and sea anemones. It contains a harpoon-like structure called a nematocyst, which is used for defense and capturing prey by injecting venom.
When a stinging cell, also known as a cnidocyte, comes into contact with another organism, it triggers the discharge of a harpoon-like structure called a nematocyst. The nematocyst injects venom into the target, immobilizing or deterring it. This process is crucial for capturing prey or defending against predators in cnidarians such as jellyfish and sea anemones.
Cnidocytes or namatoblasts or cnidoblasts are called stinging cells. These are concentrated around mouth and on tentacles. These help in paralyzing and capturing the prey or killing the enemy. Each cnidocyte acts as a capsule and encloses a nematocyst. The nematocyst is filled with poisonous fluid, hypotoxin, and its anterior end is drawn out into a long hollow thread which may bear spines. On being stimulated, the nematocyst is ejected and its long thread either injects poison into the body of prey, killing or paralyzing it, or coils around it.
Cnidocyte.
Nematocyst discharge is triggered by an immediate approach or a foreign stimulus. When the cell is discharged, a brand new nematocyst is created as the system in each cell can only be activated once.
Nematocyst discharge is triggered by an immediate approach or a foreign stimulus. When the cell is discharged, a brand new nematocyst is created as the system in each cell can only be activated once.
s a type of venomous cell unique to the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). The cnidocyte cell provides a means for them to catch prey and defend themselves from predators. Despite being morphologically simple lacking a skeleton and usually being sessile, cnidarians prey on fish and crustaceans. A cnidocyte fires a structure that contains the toxin, from a characteristic sub-cellular organelle called a cnidocyst (also known as a cnida or nematocyst). This is responsible for the stings delivered by jellyfish. s a type of venomous cell unique to the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). The cnidocyte cell provides a means for them to catch prey and defend themselves from predators. Despite being morphologically simple lacking a skeleton and usually being sessile, cnidarians prey on fish and crustaceans. A cnidocyte fires a structure that contains the toxin, from a characteristic sub-cellular organelle called a cnidocyst (also known as a cnida or nematocyst). This is responsible for the stings delivered by jellyfish.
prey capture