Gastrodermis: Difference between revisions

Latest revision as of 16:33, 16 February 2025

Gastrodermis[edit]

The gastrodermis is a tissue layer found in cnidarians, such as jellyfish, corals, and sea anemones. It lines the gastrovascular cavity, which is the primary site of digestion and nutrient absorption in these organisms. The gastrodermis is derived from the endoderm during embryonic development and plays a crucial role in the physiology of cnidarians.

Structure[edit]

The gastrodermis is composed of a single layer of cells that are specialized for various functions. These cells include:

Nutritive-muscular cells: These cells are responsible for the digestion of food particles. They contain digestive enzymes and are capable of phagocytosis, engulfing food particles and breaking them down intracellularly.
Gland cells: These cells secrete digestive enzymes into the gastrovascular cavity to aid in the extracellular digestion of food.
Ciliated cells: These cells have cilia that help to circulate the contents of the gastrovascular cavity, ensuring that nutrients are evenly distributed and waste products are expelled.

Function[edit]

The primary function of the gastrodermis is to facilitate digestion and nutrient absorption. In cnidarians, digestion occurs in two stages:

1. Extracellular digestion: Digestive enzymes secreted by gland cells break down food particles in the gastrovascular cavity. 2. Intracellular digestion: Nutritive-muscular cells engulf the partially digested food particles and complete the digestion process within their vacuoles.

The gastrodermis also plays a role in gas exchange and the expulsion of waste products. The thin layer of cells allows for the diffusion of oxygen and carbon dioxide, as well as the removal of nitrogenous wastes.

Related pages[edit]

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-'''Gastrodermis''' is the inner lining of the [[gastrovascular cavity]] of [[Cnidaria]], such as [[jellyfish]], [[corals]], and [[sea anemones]]. This layer is primarily involved in digestion, absorption of nutrients, and sometimes contains specialized cells for gas exchange. The gastrodermis is one of the two main layers of cells that arise from the embryonic [[endoderm]], the other being the [[epidermis]] which forms the outer layer.
+== Gastrodermis ==
-==Structure==
+The '''gastrodermis''' is a tissue layer found in [[cnidarians]], such as [[jellyfish]], [[corals]], and [[sea anemones]]. It lines the [[gastrovascular cavity]], which is the primary site of digestion and nutrient absorption in these organisms. The gastrodermis is derived from the endoderm during embryonic development and plays a crucial role in the physiology of cnidarians.
-The gastrodermis is composed of a simple columnar epithelium, which includes various types of cells such as nutritive-muscular cells, gland cells, and cnidocytes in some cnidarians. Nutritive-muscular cells are multifunctional, playing a role in both digestion and the contraction of the gastrovascular cavity. Gland cells secrete digestive enzymes that break down prey items. In some cnidarians, the gastrodermis may also contain [[photosynthetic]] [[zooxanthellae]], especially in corals, where they play a significant role in the nutrient supply of the host.
-==Function==
+[[File:Jellyfish_cross_section_numbered.svg|thumb|right|300px|Cross-section of a jellyfish showing the gastrodermis (numbered).]]
-The primary function of the gastrodermis is digestion. It secretes digestive enzymes into the gastrovascular cavity to break down food particles. The resulting nutrients are then absorbed through the gastrodermis and distributed throughout the organism. In addition to digestion and absorption, the gastrodermis in some cnidarians is involved in gas exchange and the removal of waste products.
-==Comparison with Other Layers==
+== Structure ==
-The gastrodermis is distinct from the [[epidermis]], which is the outermost tissue layer in cnidarians. While the epidermis is involved in protection, sensation, and locomotion, the gastrodermis is primarily concerned with the functions related to the gastrovascular cavity. Between the epidermis and gastrodermis lies the [[mesoglea]], a non-cellular jelly-like substance that provides structural support and can act as a hydrostatic skeleton in some cnidarians.
-==Evolutionary Significance==
+The gastrodermis is composed of a single layer of cells that are specialized for various functions. These cells include:
-The presence of a gastrodermis is a characteristic feature of the phylum Cnidaria, highlighting a simple, yet effective, two-layered body plan that has been successful across millions of years of evolution. This structure allows for an efficient distribution of nutrients and gases throughout the organism, despite the absence of complex organs like a heart or lungs.
-==Clinical Relevance==
+* '''Nutritive-muscular cells''': These cells are responsible for the digestion of food particles. They contain digestive enzymes and are capable of phagocytosis, engulfing food particles and breaking them down intracellularly.
-While the gastrodermis itself is not directly involved in human health, understanding its function and structure can provide insights into basic biological processes such as digestion and cellular nutrition. Additionally, the study of cnidarian gastrodermis can contribute to the understanding of coral reef health and the impacts of environmental changes on marine ecosystems.
+* '''Gland cells''': These cells secrete digestive enzymes into the gastrovascular cavity to aid in the extracellular digestion of food.
+* '''Ciliated cells''': These cells have cilia that help to circulate the contents of the gastrovascular cavity, ensuring that nutrients are evenly distributed and waste products are expelled.
-[[Category:Cnidaria]]
+== Function ==
-[[Category:Animal anatomy]]
-{{biology-stub}}
+The primary function of the gastrodermis is to facilitate digestion and nutrient absorption. In cnidarians, digestion occurs in two stages:
+. '''Extracellular digestion''': Digestive enzymes secreted by gland cells break down food particles in the gastrovascular cavity.
+. '''Intracellular digestion''': Nutritive-muscular cells engulf the partially digested food particles and complete the digestion process within their vacuoles.
+The gastrodermis also plays a role in gas exchange and the expulsion of waste products. The thin layer of cells allows for the diffusion of oxygen and carbon dioxide, as well as the removal of nitrogenous wastes.
+== Related pages ==
+* [[Cnidaria]]
+* [[Jellyfish]]
+* [[Coral]]
+* [[Sea anemone]]
+* [[Gastrovascular cavity]]
+{{Cnidaria}}
+[[Category:Cnidarian anatomy]]