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Nephridium
The nephridium (: nephridia) is an invertebrate organ, found in pairs and performing a function similar to the vertebrate kidneys (which originated from the chordate nephridia). Nephridia remove metabolic wastes from an animal's body. Nephridia come in two basic categories: metanephridia and protonephridia. All nephridia- and kidney- having animals belong to the clade Nephrozoa. Metanephridia A metanephridium (''meta'' = "after") is a type of excretory gland found in many types of invertebrates such as annelids, arthropods and mollusca. (In mollusca, it is known as the Bojanus organ.) A metanephridium typically consists of the nephrostome (a ciliated funnel) opening into the body cavity, connected to a duct which may be variously glandularized, folded or expanded (vesiculate) and which typically opens to the organism's exterior. These ciliated tubules pump water carrying surplus ions, metabolic waste, toxins from food, and useless hormones out of the organism by directing th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidney (vertebrates)
The kidneys are a pair of Organ (biology), organs of the excretory system in vertebrates, which maintain the balance of water and electrolytes in the body (osmoregulation), filter the blood, remove Metabolic pathway, metabolic waste products, and, in many vertebrates, also produce hormones (in particular, renin) and maintain blood pressure. In healthy vertebrates, the kidneys maintain homeostasis of extracellular fluid in the body. When the blood is being filtered, the kidneys form urine, which consists of water and excess or unnecessary substances, the urine is then excreted from the body through other organs, which in vertebrates, depending on the species, may include the ureter, urinary bladder, cloaca, and urethra. All vertebrates have kidneys. The kidneys are the main organ that allows species to adapt to different environments, including Fresh water, fresh and Saline water, salt water, Terrestrial animal, terrestrial life and desert climate. Depending on the environment in wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephrozoa
Nephrozoa is a proposed major clade of bilaterian animals. Under this hypothesis, Xenacoelomorpha forms the earliest diverging branch of Bilateria, with all other bilaterians placed in Nephrozoa. It contrasts with the Xenambulacraria hypothesis, which instead posits that Xenacoelomorpha is most closely related to Ambulacraria (usually placed as Deuterostome, deuterostomes). Which hypothesis is correct has been debated, and as of 2024 the issue is unresolved. The clade is named after a key synapomorphy of the group: the presence of specialized excretory organs known as Nephridium, nephridia. Below is a proposed phylogenetic tree of Nephrozoa: References Further reading * * * External links * Bilaterians Ediacaran first appearances {{zoology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metanephridium
The nephridium (: nephridia) is an invertebrate organ, found in pairs and performing a function similar to the Kidney (vertebrates), vertebrate kidneys (which originated from the chordate nephridia). Nephridia remove Metabolism, metabolic wastes from an animal's body. Nephridia come in two basic categories: metanephridia and protonephridia. All nephridia- and kidney- having animals belong to the clade Nephrozoa. Metanephridia A metanephridium (''meta'' = "after") is a type of excretion, excretory gland found in many types of invertebrates such as annelids, arthropods and mollusca. (In mollusca, it is known as the Bojanus organ.) A metanephridium typically consists of the nephrostome (a ciliated funnel) opening into the coelom, body cavity, connected to a duct (anatomy), duct which may be variously glandularized, folded or expanded (vesiculate) and which typically opens to the organism's exterior. These ciliated tubules pump water carrying surplus ions, metabolic waste, toxins fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bojanus Organ
The organs of Bojanus or Bojanus organs are excretory glands that serve the function of kidneys in some of the molluscs. In other words, these are metanephridia that are found in some molluscs, for example in the bivalves. Some other molluscs have another type of organ for excretion Excretion is elimination of metabolic waste, which is an essential process in all organisms. In vertebrates, this is primarily carried out by the lungs, Kidney (vertebrates), kidneys, and skin. This is in contrast with secretion, where the substa ... called Keber's organ. The Bojanus organ is named after Ludwig Heinrich Bojanus, who first described it. The excretory system of a bivalve consists of a pair of kidneys called the organ of bojanus. These are situated one of each side of the body below the pericardium. Each kidney consist of 2 part (1)- glandular part (2)- a thin walled ciliated urinary bladder. References * Encyclopædia Britannica Further reading * * Organs (anatomy) Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell (biology)
The cell is the basic structural and functional unit of all life, forms of life. Every cell consists of cytoplasm enclosed within a Cell membrane, membrane; many cells contain organelles, each with a specific function. The term comes from the Latin word meaning 'small room'. Most cells are only visible under a light microscope, microscope. Cells Abiogenesis, emerged on Earth about 4 billion years ago. All cells are capable of Self-replication, replication, protein synthesis, and cell motility, motility. Cells are broadly categorized into two types: eukaryotic cells, which possess a Cell nucleus, nucleus, and prokaryotic, prokaryotic cells, which lack a nucleus but have a nucleoid region. Prokaryotes are single-celled organisms such as bacteria, whereas eukaryotes can be either single-celled, such as amoebae, or multicellular organism, multicellular, such as some algae, plants, animals, and fungi. Eukaryotic cells contain organelles including Mitochondrion, mitochondria, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephrostome
The nephrostome is the funnel-like component of a metanephridium. It is always oriented towards the coelom. The nephrostome is covered from the inside with cilia, which push the water, metabolic wastes, unnecessary hormones A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physiology and behavior. Hormones a ... and other substances into the metanephridium. References Annelid anatomy {{animal-anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephridiopore
A nephridiopore is part of the nephridium, an excretory organ found in many organisms, such as flatworms and annelids. Polychaetes typically release their gametes into the water column using nephridiopores. Nephridia are homologous to nephrons or uriniferous tubules found in the kidney of humans. Nephridiopores are present in ventral region. The nephridium consists of an opening called the nephrostome, a long convoluted tubule, and another opening called the nephridiopore. Body fluids are filtered in through the nephrostome and passed through the convoluted tubule system. Essential substances are reabsorbed through active mechanisms and waste products are secreted back into the lumen of the tube. The resulting excretory fluid or urine Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urine
Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (males) or urethral meatus of the vulva (females) during urination. In other vertebrates, urine is excreted through the cloaca. Urine contains water-soluble by-products of Cell (biology), cellular metabolism that are rich in nitrogen and must be clearance (medicine), cleared from the Circulatory system, bloodstream, such as urea, uric acid and creatinine. A urinalysis can detect nitrogenous wastes of the mammalian body. Urine plays an important role in the earth's nitrogen cycle. In balanced ecosystems, urine fertilizes the soil and thus helps plants to grow. Therefore, Reuse of excreta, urine can be used as a fertilizer. Some animals use it to territory (animal)#Scent marking, mark their territories. Historically, aged or fermented urine (kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selective Reabsorption
Selective reabsorption is the process whereby certain molecules (e.g. ions, glucose and amino acids), after being filtered out of the capillaries along with nitrogenous waste products (i.e. urea) and water in the glomerulus, are reabsorbed from the filtrate as they pass through the nephron. Selective reabsorbtion occurs in the PCT (proximal convoluted tubule). The PCT is highly permeable meaning it is easy for molecules to diffuse through it. A basic outline of the process *The co-transport sodium-potassium pump actively transports sodium out of the PCT ( proximal convoluted tubule) wall (using energy from converting ATP to ADP + Pi) to maintain a low Na+ concentration gradient in the wall. *This low concentration gradient means that Na+ ions from the glomerulus filtrate can easily passively diffuse into the wall of the PCT. *However, the Na+ ions cannot diffuse freely across the membrane, but can only enter through special transporter (carrier) proteins in the membrane o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invertebrate
Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate subphylum Vertebrata, i.e. vertebrates. Well-known Phylum, phyla of invertebrates include arthropods, molluscs, annelids, echinoderms, flatworms, cnidarians, and sponges. The majority of animal species are invertebrates; one estimate puts the figure at 97%. Many invertebrate taxon, taxa have a greater number and diversity of species than the entire subphylum of Vertebrata. Invertebrates vary widely in size, from 10 Micrometre, μm (0.0004 in) myxozoans to the 9–10 m (30–33 ft) colossal squid. Some so-called invertebrates, such as the Tunicata and Cephalochordata, are actually sister chordate subphyla to Vertebrata, being more closely related to vertebrates than to other invertebrates. This makes the "invertebrates" para ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coxal Gland
The coxal gland is a gland found in some arthropods, for collecting and excreting urine. They are found in all arachnids (with the exception of some Acari), and in other chelicerates, such as horseshoe crabs. The coxal gland is thought to be homologous with the antennal gland of crustaceans. The gland consists of an end sac (''saccule''), a long duct (''labyrinth'') and a terminal bladder (''reservoir''). There is generally only one pair (two in some spiders), and they open on the coxae of the walking legs or at the base of the second antennae in the case of the crustacean antennal gland. The coxal secretion of adult female ticks of '' Ornithodoros erraticus'' contains a sex pheromone. In Spiders, the coxal glands should not be confused with segmentary organs, a whole set of even and symmetrical exocrine structures, apparently metamerized, located in the prosoma of spiders on the base of the appendages, the most important being the retrognathocoxal glands. They were discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hormone
A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physiology and behavior. Hormones are required for the normal development of animals, plants and fungi. Due to the broad definition of a hormone (as a signaling molecule that exerts its effects far from its site of production), numerous kinds of molecules can be classified as hormones. Among the substances that can be considered hormones, are eicosanoids (e.g. prostaglandins and thromboxanes), steroids (e.g. Estrogen, oestrogen and brassinosteroid), amino acid derivatives (e.g. epinephrine and auxin), protein or peptides (e.g. insulin and CLE peptides), and gases (e.g. ethylene and nitric oxide). Hormones are used to communicate between organ (anatomy), organs and Tissue (biology), tissues. In vertebrates, hormones are responsible for regulating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
