. Need a reference? They can also reproduce via budding, where new sponges simply grow off the existing sponge. Gemmules help the sponge to tide over unfavourable conditions. The regeneration power of sponges is demonstrated by the experiments carried out by Wilson in 1907. Now these spermatogonia undergo two to three maturation divisions to form spermatocytes and these spermatocytes later give rise to spermatozoa. A gemmule is a small, round, hard ball consisting of internal mass of food laden archaeocytes surrounded by chitinous double membrane. Pores are also called Ostia. ASEXUAL REPRODUCTION When reproducing asexually, sea sponges form buds which are also known as gemmules. Thus epithelial tissue regenerates readily whereas highly differentiated tissues such as muscle or nerve tissue have limited power of regeneration. Juveniles drift or swim freely, while adults are stationary. Sponges are undoubtedly the best at regeneration. Budding 2. Hypertrophy is the non-tumorous enlargement of a tissue or an organ as a result of the increase in the size rather than the number of constituent cells. The archeocyte hatches and becomes a new sponge. Asexual reproduction. Asexual reproduction does not need the pair to reproduce. ASEXUAL REPRODUCTION IN SPONGES 1. Brush up on your geography and finally learn what countries are in Eastern Europe with our maps. This spermatogonium is surrounded by one or more flattened cover cells to form spermatocyst. (adsbygoogle = window.adsbygoogle || []).push({ Sponges which have low grade of organization exhibit high degree of regeneration power. As sponges can be cut up tiny pieces or even mashed up into a paste and as long as they have two special cells called collencytes (which produce mesohyl the gelatinous matrix in the sponge that forms a sort of psuedotissue) and archeocytes (which produce all the other cells in the sponges body) the sponge will survive and reform into the spongelet and then into an adult sponge. According to the experiments conducted by Bergquist, if a tissue if grafted in a sponge from another sponge of the same species, the host and the graft will grow together. enable_page_level_ads: true asexual reproduction. According to the experiments conducted by Humphrey, calcium and magnesium ions are necessary for regeneration. Pieces of sponge are able to regenerate into whole new sponges. If a sponge is chopped into small pieces, run through a meat grinder and then squeezed through a fine blotting cloth then all the sponge cells are separated from each other. By this method the number of individuals in the colony may increase or new colonies may be formed. Amphiblastula: It is hollow, oval larval stage characteristic of calcareous sponges (Scypha). Internal budding takes place by the formation of internal buds called gemmules. The entire larva is covered by flagella. The summer generation dies off in autumn living behind gemmules which hatch in spring. Asexual reproduction occurs by budding or by fragmentation. The archaeocyte is protected until the conditions for a new sponge to develop are right. We have loaded Previous years questions with explanations...for all competitive exams. There the buds begin to grow into clones, or genetically identical sponges, of their parents. Since the reproduction is asexual, the newly created Stove Pipe Sponge is a clone and is genetically identical to the parent sponge. FEN Learning is part of Sandbox Networks, a digital learning company that operates education services and products for the 21st century. This type of reproduction is the result of the body´s fragmentation, which occurs due to exposure to unfavorable environmental conditions or as a part of the normal life cycle. sponges reproduce by asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult Green Finger Sponge are able to regenerate into whole new sponges. The Columbia Electronic Encyclopedia, 6th ed. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. It is very unusual method of asexual reproduction found in sponges. Gemmules are internal buds found in sponges and are involved in asexual reproduction.It is an asexually reproduced mass of cells, that is capable of developing into a new organism i.e., an adult sponge. Learn more about the world with our collection of regional and country maps. Sexual reproduction also occurs. The sperm and ova are also known to be derived from choanocytes which later undergo gametogenesis to form sperm or ova. See more Encyclopedia articles on: Zoology: Invertebrates. We've got you covered with our map collection. Another form of asexual reproduction that some sponges are capable of is called budding. The technique of asexual reproduction most commonly used in the production of fruit trees is _____. Most sponges are hermaphroditic, the same individual producing eggs and sperm, but in some species the sexes are separate. Study Score Infoplease knows the value of having sources you can trust. External buds are formed when fragments of a sea sponge's body are broken off by water currents and carried to other locations. google_ad_client: "ca-pub-5414192315724946", Freshwater sponges are multicellular, marine living species of a Kingdom Phylum – Porifera. Describe the formation of reduction bodies. Pieces of sponge are able to regenerate into whole new sponges. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules can withstand freezing and considerably greater degree of desiccation than the adult sponges. Asexual reproduction is when a tiny piece of an adult sponge breaks off and it becomes a new sponge. asexual reproduction in sponges. … Sexual reproduction … Gemmules are aggregates of sponge tissue and food, covered by a hard coating containing spicules or spongin fibers. How does regeneration help in sponges? When fully grown the oocyte undergoes two maturation divisions to form ovum which lies in the wall of the radial canal or spongocoel, ready to be fertilized by the sperm of other sponge. Asexual Reproduction: 'Budding' a New Generation. These gemmules are tough and coated with a dormant cluster of embryonic cells. Asexual methods of reproduction include: the growth of stolons that develop into new individuals; a bud separating from the parent sponge and creating a new sponge elsewhere; and the simple act of parts of a sponge breaking of and establishing in a new location. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules are internals buds formed within the sponge body. Not sure about the geography of the middle east? This process of asexual reproduction is found in planaria and hydra. // ]]>. ASEXUAL REPRODUCTION Regeneration All sponges possess a remarkable ability to regenerate lost parts. Role in asexual reproduction. An outgrowth from the sponge body wall may arise either at the base or near the attached end to form bud. on Apr 28, 2018 at 08:47 am. In our sponge model (Oscarella lobularis, Porifera, Homoscleromorpha) gametogenesis takes place once a year, in spring and summe r. The lashing movement of the tail helps the spermatozoon to reach other sponges. The life history of such sponges illustrates alternation of generation. The sperm and ova are derived from the undifferentiated amoebocytes called as archaeocytes. - Sponges reproduce by both asexual and sexual means. Like and Follow us on Facebook and Telegram for latest updates... // 25 Healthy Breakfast Foods, Baby Chiropractor Houston, Canon C500 Mark Ii Vs Alexa, Abolish Ice Shirt, Mina Lobata Vine, How To Cook Adzuki Beans In A Slow Cooker, Cna Resume No Experience, Turkey Shepherds Pie Frozen Vegetables, Toll House Pie Bars, Corn Plant Stalk Turning Brown, Drunk Elephant Dopp Kit Uk, How To Prevent Mold In Humid Climate, Kerastase Oleo Curl How To Use, The Knitter's Handy Book Of Patterns, Fitbit Scale Aria, "/> . Need a reference? They can also reproduce via budding, where new sponges simply grow off the existing sponge. Gemmules help the sponge to tide over unfavourable conditions. The regeneration power of sponges is demonstrated by the experiments carried out by Wilson in 1907. Now these spermatogonia undergo two to three maturation divisions to form spermatocytes and these spermatocytes later give rise to spermatozoa. A gemmule is a small, round, hard ball consisting of internal mass of food laden archaeocytes surrounded by chitinous double membrane. Pores are also called Ostia. ASEXUAL REPRODUCTION When reproducing asexually, sea sponges form buds which are also known as gemmules. Thus epithelial tissue regenerates readily whereas highly differentiated tissues such as muscle or nerve tissue have limited power of regeneration. Juveniles drift or swim freely, while adults are stationary. Sponges are undoubtedly the best at regeneration. Budding 2. Hypertrophy is the non-tumorous enlargement of a tissue or an organ as a result of the increase in the size rather than the number of constituent cells. The archeocyte hatches and becomes a new sponge. Asexual reproduction. Asexual reproduction does not need the pair to reproduce. ASEXUAL REPRODUCTION IN SPONGES 1. Brush up on your geography and finally learn what countries are in Eastern Europe with our maps. This spermatogonium is surrounded by one or more flattened cover cells to form spermatocyst. (adsbygoogle = window.adsbygoogle || []).push({ Sponges which have low grade of organization exhibit high degree of regeneration power. As sponges can be cut up tiny pieces or even mashed up into a paste and as long as they have two special cells called collencytes (which produce mesohyl the gelatinous matrix in the sponge that forms a sort of psuedotissue) and archeocytes (which produce all the other cells in the sponges body) the sponge will survive and reform into the spongelet and then into an adult sponge. According to the experiments conducted by Bergquist, if a tissue if grafted in a sponge from another sponge of the same species, the host and the graft will grow together. enable_page_level_ads: true asexual reproduction. According to the experiments conducted by Humphrey, calcium and magnesium ions are necessary for regeneration. Pieces of sponge are able to regenerate into whole new sponges. If a sponge is chopped into small pieces, run through a meat grinder and then squeezed through a fine blotting cloth then all the sponge cells are separated from each other. By this method the number of individuals in the colony may increase or new colonies may be formed. Amphiblastula: It is hollow, oval larval stage characteristic of calcareous sponges (Scypha). Internal budding takes place by the formation of internal buds called gemmules. The entire larva is covered by flagella. The summer generation dies off in autumn living behind gemmules which hatch in spring. Asexual reproduction occurs by budding or by fragmentation. The archaeocyte is protected until the conditions for a new sponge to develop are right. We have loaded Previous years questions with explanations...for all competitive exams. There the buds begin to grow into clones, or genetically identical sponges, of their parents. Since the reproduction is asexual, the newly created Stove Pipe Sponge is a clone and is genetically identical to the parent sponge. FEN Learning is part of Sandbox Networks, a digital learning company that operates education services and products for the 21st century. This type of reproduction is the result of the body´s fragmentation, which occurs due to exposure to unfavorable environmental conditions or as a part of the normal life cycle. sponges reproduce by asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult Green Finger Sponge are able to regenerate into whole new sponges. The Columbia Electronic Encyclopedia, 6th ed. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. It is very unusual method of asexual reproduction found in sponges. Gemmules are internal buds found in sponges and are involved in asexual reproduction.It is an asexually reproduced mass of cells, that is capable of developing into a new organism i.e., an adult sponge. Learn more about the world with our collection of regional and country maps. Sexual reproduction also occurs. The sperm and ova are also known to be derived from choanocytes which later undergo gametogenesis to form sperm or ova. See more Encyclopedia articles on: Zoology: Invertebrates. We've got you covered with our map collection. Another form of asexual reproduction that some sponges are capable of is called budding. The technique of asexual reproduction most commonly used in the production of fruit trees is _____. Most sponges are hermaphroditic, the same individual producing eggs and sperm, but in some species the sexes are separate. Study Score Infoplease knows the value of having sources you can trust. External buds are formed when fragments of a sea sponge's body are broken off by water currents and carried to other locations. google_ad_client: "ca-pub-5414192315724946", Freshwater sponges are multicellular, marine living species of a Kingdom Phylum – Porifera. Describe the formation of reduction bodies. Pieces of sponge are able to regenerate into whole new sponges. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules can withstand freezing and considerably greater degree of desiccation than the adult sponges. Asexual reproduction is when a tiny piece of an adult sponge breaks off and it becomes a new sponge. asexual reproduction in sponges. … Sexual reproduction … Gemmules are aggregates of sponge tissue and food, covered by a hard coating containing spicules or spongin fibers. How does regeneration help in sponges? When fully grown the oocyte undergoes two maturation divisions to form ovum which lies in the wall of the radial canal or spongocoel, ready to be fertilized by the sperm of other sponge. Asexual Reproduction: 'Budding' a New Generation. These gemmules are tough and coated with a dormant cluster of embryonic cells. Asexual methods of reproduction include: the growth of stolons that develop into new individuals; a bud separating from the parent sponge and creating a new sponge elsewhere; and the simple act of parts of a sponge breaking of and establishing in a new location. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules are internals buds formed within the sponge body. Not sure about the geography of the middle east? This process of asexual reproduction is found in planaria and hydra. // ]]>. ASEXUAL REPRODUCTION Regeneration All sponges possess a remarkable ability to regenerate lost parts. Role in asexual reproduction. An outgrowth from the sponge body wall may arise either at the base or near the attached end to form bud. on Apr 28, 2018 at 08:47 am. In our sponge model (Oscarella lobularis, Porifera, Homoscleromorpha) gametogenesis takes place once a year, in spring and summe r. The lashing movement of the tail helps the spermatozoon to reach other sponges. The life history of such sponges illustrates alternation of generation. The sperm and ova are derived from the undifferentiated amoebocytes called as archaeocytes. - Sponges reproduce by both asexual and sexual means. Like and Follow us on Facebook and Telegram for latest updates... // 25 Healthy Breakfast Foods, Baby Chiropractor Houston, Canon C500 Mark Ii Vs Alexa, Abolish Ice Shirt, Mina Lobata Vine, How To Cook Adzuki Beans In A Slow Cooker, Cna Resume No Experience, Turkey Shepherds Pie Frozen Vegetables, Toll House Pie Bars, Corn Plant Stalk Turning Brown, Drunk Elephant Dopp Kit Uk, How To Prevent Mold In Humid Climate, Kerastase Oleo Curl How To Use, The Knitter's Handy Book Of Patterns, Fitbit Scale Aria, "/> . Need a reference? They can also reproduce via budding, where new sponges simply grow off the existing sponge. Gemmules help the sponge to tide over unfavourable conditions. The regeneration power of sponges is demonstrated by the experiments carried out by Wilson in 1907. Now these spermatogonia undergo two to three maturation divisions to form spermatocytes and these spermatocytes later give rise to spermatozoa. A gemmule is a small, round, hard ball consisting of internal mass of food laden archaeocytes surrounded by chitinous double membrane. Pores are also called Ostia. ASEXUAL REPRODUCTION When reproducing asexually, sea sponges form buds which are also known as gemmules. Thus epithelial tissue regenerates readily whereas highly differentiated tissues such as muscle or nerve tissue have limited power of regeneration. Juveniles drift or swim freely, while adults are stationary. Sponges are undoubtedly the best at regeneration. Budding 2. Hypertrophy is the non-tumorous enlargement of a tissue or an organ as a result of the increase in the size rather than the number of constituent cells. The archeocyte hatches and becomes a new sponge. Asexual reproduction. Asexual reproduction does not need the pair to reproduce. ASEXUAL REPRODUCTION IN SPONGES 1. Brush up on your geography and finally learn what countries are in Eastern Europe with our maps. This spermatogonium is surrounded by one or more flattened cover cells to form spermatocyst. (adsbygoogle = window.adsbygoogle || []).push({ Sponges which have low grade of organization exhibit high degree of regeneration power. As sponges can be cut up tiny pieces or even mashed up into a paste and as long as they have two special cells called collencytes (which produce mesohyl the gelatinous matrix in the sponge that forms a sort of psuedotissue) and archeocytes (which produce all the other cells in the sponges body) the sponge will survive and reform into the spongelet and then into an adult sponge. According to the experiments conducted by Bergquist, if a tissue if grafted in a sponge from another sponge of the same species, the host and the graft will grow together. enable_page_level_ads: true asexual reproduction. According to the experiments conducted by Humphrey, calcium and magnesium ions are necessary for regeneration. Pieces of sponge are able to regenerate into whole new sponges. If a sponge is chopped into small pieces, run through a meat grinder and then squeezed through a fine blotting cloth then all the sponge cells are separated from each other. By this method the number of individuals in the colony may increase or new colonies may be formed. Amphiblastula: It is hollow, oval larval stage characteristic of calcareous sponges (Scypha). Internal budding takes place by the formation of internal buds called gemmules. The entire larva is covered by flagella. The summer generation dies off in autumn living behind gemmules which hatch in spring. Asexual reproduction occurs by budding or by fragmentation. The archaeocyte is protected until the conditions for a new sponge to develop are right. We have loaded Previous years questions with explanations...for all competitive exams. There the buds begin to grow into clones, or genetically identical sponges, of their parents. Since the reproduction is asexual, the newly created Stove Pipe Sponge is a clone and is genetically identical to the parent sponge. FEN Learning is part of Sandbox Networks, a digital learning company that operates education services and products for the 21st century. This type of reproduction is the result of the body´s fragmentation, which occurs due to exposure to unfavorable environmental conditions or as a part of the normal life cycle. sponges reproduce by asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult Green Finger Sponge are able to regenerate into whole new sponges. The Columbia Electronic Encyclopedia, 6th ed. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. It is very unusual method of asexual reproduction found in sponges. Gemmules are internal buds found in sponges and are involved in asexual reproduction.It is an asexually reproduced mass of cells, that is capable of developing into a new organism i.e., an adult sponge. Learn more about the world with our collection of regional and country maps. Sexual reproduction also occurs. The sperm and ova are also known to be derived from choanocytes which later undergo gametogenesis to form sperm or ova. See more Encyclopedia articles on: Zoology: Invertebrates. We've got you covered with our map collection. Another form of asexual reproduction that some sponges are capable of is called budding. The technique of asexual reproduction most commonly used in the production of fruit trees is _____. Most sponges are hermaphroditic, the same individual producing eggs and sperm, but in some species the sexes are separate. Study Score Infoplease knows the value of having sources you can trust. External buds are formed when fragments of a sea sponge's body are broken off by water currents and carried to other locations. google_ad_client: "ca-pub-5414192315724946", Freshwater sponges are multicellular, marine living species of a Kingdom Phylum – Porifera. Describe the formation of reduction bodies. Pieces of sponge are able to regenerate into whole new sponges. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules can withstand freezing and considerably greater degree of desiccation than the adult sponges. Asexual reproduction is when a tiny piece of an adult sponge breaks off and it becomes a new sponge. asexual reproduction in sponges. … Sexual reproduction … Gemmules are aggregates of sponge tissue and food, covered by a hard coating containing spicules or spongin fibers. How does regeneration help in sponges? When fully grown the oocyte undergoes two maturation divisions to form ovum which lies in the wall of the radial canal or spongocoel, ready to be fertilized by the sperm of other sponge. Asexual Reproduction: 'Budding' a New Generation. These gemmules are tough and coated with a dormant cluster of embryonic cells. Asexual methods of reproduction include: the growth of stolons that develop into new individuals; a bud separating from the parent sponge and creating a new sponge elsewhere; and the simple act of parts of a sponge breaking of and establishing in a new location. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules are internals buds formed within the sponge body. Not sure about the geography of the middle east? This process of asexual reproduction is found in planaria and hydra. // ]]>. ASEXUAL REPRODUCTION Regeneration All sponges possess a remarkable ability to regenerate lost parts. Role in asexual reproduction. An outgrowth from the sponge body wall may arise either at the base or near the attached end to form bud. on Apr 28, 2018 at 08:47 am. In our sponge model (Oscarella lobularis, Porifera, Homoscleromorpha) gametogenesis takes place once a year, in spring and summe r. The lashing movement of the tail helps the spermatozoon to reach other sponges. The life history of such sponges illustrates alternation of generation. The sperm and ova are derived from the undifferentiated amoebocytes called as archaeocytes. - Sponges reproduce by both asexual and sexual means. Like and Follow us on Facebook and Telegram for latest updates... // 25 Healthy Breakfast Foods, Baby Chiropractor Houston, Canon C500 Mark Ii Vs Alexa, Abolish Ice Shirt, Mina Lobata Vine, How To Cook Adzuki Beans In A Slow Cooker, Cna Resume No Experience, Turkey Shepherds Pie Frozen Vegetables, Toll House Pie Bars, Corn Plant Stalk Turning Brown, Drunk Elephant Dopp Kit Uk, How To Prevent Mold In Humid Climate, Kerastase Oleo Curl How To Use, The Knitter's Handy Book Of Patterns, Fitbit Scale Aria, "/> . Need a reference? They can also reproduce via budding, where new sponges simply grow off the existing sponge. Gemmules help the sponge to tide over unfavourable conditions. The regeneration power of sponges is demonstrated by the experiments carried out by Wilson in 1907. Now these spermatogonia undergo two to three maturation divisions to form spermatocytes and these spermatocytes later give rise to spermatozoa. A gemmule is a small, round, hard ball consisting of internal mass of food laden archaeocytes surrounded by chitinous double membrane. Pores are also called Ostia. ASEXUAL REPRODUCTION When reproducing asexually, sea sponges form buds which are also known as gemmules. Thus epithelial tissue regenerates readily whereas highly differentiated tissues such as muscle or nerve tissue have limited power of regeneration. Juveniles drift or swim freely, while adults are stationary. Sponges are undoubtedly the best at regeneration. Budding 2. Hypertrophy is the non-tumorous enlargement of a tissue or an organ as a result of the increase in the size rather than the number of constituent cells. The archeocyte hatches and becomes a new sponge. Asexual reproduction. Asexual reproduction does not need the pair to reproduce. ASEXUAL REPRODUCTION IN SPONGES 1. Brush up on your geography and finally learn what countries are in Eastern Europe with our maps. This spermatogonium is surrounded by one or more flattened cover cells to form spermatocyst. (adsbygoogle = window.adsbygoogle || []).push({ Sponges which have low grade of organization exhibit high degree of regeneration power. As sponges can be cut up tiny pieces or even mashed up into a paste and as long as they have two special cells called collencytes (which produce mesohyl the gelatinous matrix in the sponge that forms a sort of psuedotissue) and archeocytes (which produce all the other cells in the sponges body) the sponge will survive and reform into the spongelet and then into an adult sponge. According to the experiments conducted by Bergquist, if a tissue if grafted in a sponge from another sponge of the same species, the host and the graft will grow together. enable_page_level_ads: true asexual reproduction. According to the experiments conducted by Humphrey, calcium and magnesium ions are necessary for regeneration. Pieces of sponge are able to regenerate into whole new sponges. If a sponge is chopped into small pieces, run through a meat grinder and then squeezed through a fine blotting cloth then all the sponge cells are separated from each other. By this method the number of individuals in the colony may increase or new colonies may be formed. Amphiblastula: It is hollow, oval larval stage characteristic of calcareous sponges (Scypha). Internal budding takes place by the formation of internal buds called gemmules. The entire larva is covered by flagella. The summer generation dies off in autumn living behind gemmules which hatch in spring. Asexual reproduction occurs by budding or by fragmentation. The archaeocyte is protected until the conditions for a new sponge to develop are right. We have loaded Previous years questions with explanations...for all competitive exams. There the buds begin to grow into clones, or genetically identical sponges, of their parents. Since the reproduction is asexual, the newly created Stove Pipe Sponge is a clone and is genetically identical to the parent sponge. FEN Learning is part of Sandbox Networks, a digital learning company that operates education services and products for the 21st century. This type of reproduction is the result of the body´s fragmentation, which occurs due to exposure to unfavorable environmental conditions or as a part of the normal life cycle. sponges reproduce by asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult Green Finger Sponge are able to regenerate into whole new sponges. The Columbia Electronic Encyclopedia, 6th ed. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. It is very unusual method of asexual reproduction found in sponges. Gemmules are internal buds found in sponges and are involved in asexual reproduction.It is an asexually reproduced mass of cells, that is capable of developing into a new organism i.e., an adult sponge. Learn more about the world with our collection of regional and country maps. Sexual reproduction also occurs. The sperm and ova are also known to be derived from choanocytes which later undergo gametogenesis to form sperm or ova. See more Encyclopedia articles on: Zoology: Invertebrates. We've got you covered with our map collection. Another form of asexual reproduction that some sponges are capable of is called budding. The technique of asexual reproduction most commonly used in the production of fruit trees is _____. Most sponges are hermaphroditic, the same individual producing eggs and sperm, but in some species the sexes are separate. Study Score Infoplease knows the value of having sources you can trust. External buds are formed when fragments of a sea sponge's body are broken off by water currents and carried to other locations. google_ad_client: "ca-pub-5414192315724946", Freshwater sponges are multicellular, marine living species of a Kingdom Phylum – Porifera. Describe the formation of reduction bodies. Pieces of sponge are able to regenerate into whole new sponges. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules can withstand freezing and considerably greater degree of desiccation than the adult sponges. Asexual reproduction is when a tiny piece of an adult sponge breaks off and it becomes a new sponge. asexual reproduction in sponges. … Sexual reproduction … Gemmules are aggregates of sponge tissue and food, covered by a hard coating containing spicules or spongin fibers. How does regeneration help in sponges? When fully grown the oocyte undergoes two maturation divisions to form ovum which lies in the wall of the radial canal or spongocoel, ready to be fertilized by the sperm of other sponge. Asexual Reproduction: 'Budding' a New Generation. These gemmules are tough and coated with a dormant cluster of embryonic cells. Asexual methods of reproduction include: the growth of stolons that develop into new individuals; a bud separating from the parent sponge and creating a new sponge elsewhere; and the simple act of parts of a sponge breaking of and establishing in a new location. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules are internals buds formed within the sponge body. Not sure about the geography of the middle east? This process of asexual reproduction is found in planaria and hydra. // ]]>. ASEXUAL REPRODUCTION Regeneration All sponges possess a remarkable ability to regenerate lost parts. Role in asexual reproduction. An outgrowth from the sponge body wall may arise either at the base or near the attached end to form bud. on Apr 28, 2018 at 08:47 am. In our sponge model (Oscarella lobularis, Porifera, Homoscleromorpha) gametogenesis takes place once a year, in spring and summe r. The lashing movement of the tail helps the spermatozoon to reach other sponges. The life history of such sponges illustrates alternation of generation. The sperm and ova are derived from the undifferentiated amoebocytes called as archaeocytes. - Sponges reproduce by both asexual and sexual means. Like and Follow us on Facebook and Telegram for latest updates... // 25 Healthy Breakfast Foods, Baby Chiropractor Houston, Canon C500 Mark Ii Vs Alexa, Abolish Ice Shirt, Mina Lobata Vine, How To Cook Adzuki Beans In A Slow Cooker, Cna Resume No Experience, Turkey Shepherds Pie Frozen Vegetables, Toll House Pie Bars, Corn Plant Stalk Turning Brown, Drunk Elephant Dopp Kit Uk, How To Prevent Mold In Humid Climate, Kerastase Oleo Curl How To Use, The Knitter's Handy Book Of Patterns, Fitbit Scale Aria, "/> . Need a reference? They can also reproduce via budding, where new sponges simply grow off the existing sponge. Gemmules help the sponge to tide over unfavourable conditions. The regeneration power of sponges is demonstrated by the experiments carried out by Wilson in 1907. Now these spermatogonia undergo two to three maturation divisions to form spermatocytes and these spermatocytes later give rise to spermatozoa. A gemmule is a small, round, hard ball consisting of internal mass of food laden archaeocytes surrounded by chitinous double membrane. Pores are also called Ostia. ASEXUAL REPRODUCTION When reproducing asexually, sea sponges form buds which are also known as gemmules. Thus epithelial tissue regenerates readily whereas highly differentiated tissues such as muscle or nerve tissue have limited power of regeneration. Juveniles drift or swim freely, while adults are stationary. Sponges are undoubtedly the best at regeneration. Budding 2. Hypertrophy is the non-tumorous enlargement of a tissue or an organ as a result of the increase in the size rather than the number of constituent cells. The archeocyte hatches and becomes a new sponge. Asexual reproduction. Asexual reproduction does not need the pair to reproduce. ASEXUAL REPRODUCTION IN SPONGES 1. Brush up on your geography and finally learn what countries are in Eastern Europe with our maps. This spermatogonium is surrounded by one or more flattened cover cells to form spermatocyst. (adsbygoogle = window.adsbygoogle || []).push({ Sponges which have low grade of organization exhibit high degree of regeneration power. As sponges can be cut up tiny pieces or even mashed up into a paste and as long as they have two special cells called collencytes (which produce mesohyl the gelatinous matrix in the sponge that forms a sort of psuedotissue) and archeocytes (which produce all the other cells in the sponges body) the sponge will survive and reform into the spongelet and then into an adult sponge. According to the experiments conducted by Bergquist, if a tissue if grafted in a sponge from another sponge of the same species, the host and the graft will grow together. enable_page_level_ads: true asexual reproduction. According to the experiments conducted by Humphrey, calcium and magnesium ions are necessary for regeneration. Pieces of sponge are able to regenerate into whole new sponges. If a sponge is chopped into small pieces, run through a meat grinder and then squeezed through a fine blotting cloth then all the sponge cells are separated from each other. By this method the number of individuals in the colony may increase or new colonies may be formed. Amphiblastula: It is hollow, oval larval stage characteristic of calcareous sponges (Scypha). Internal budding takes place by the formation of internal buds called gemmules. The entire larva is covered by flagella. The summer generation dies off in autumn living behind gemmules which hatch in spring. Asexual reproduction occurs by budding or by fragmentation. The archaeocyte is protected until the conditions for a new sponge to develop are right. We have loaded Previous years questions with explanations...for all competitive exams. There the buds begin to grow into clones, or genetically identical sponges, of their parents. Since the reproduction is asexual, the newly created Stove Pipe Sponge is a clone and is genetically identical to the parent sponge. FEN Learning is part of Sandbox Networks, a digital learning company that operates education services and products for the 21st century. This type of reproduction is the result of the body´s fragmentation, which occurs due to exposure to unfavorable environmental conditions or as a part of the normal life cycle. sponges reproduce by asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult Green Finger Sponge are able to regenerate into whole new sponges. The Columbia Electronic Encyclopedia, 6th ed. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. It is very unusual method of asexual reproduction found in sponges. Gemmules are internal buds found in sponges and are involved in asexual reproduction.It is an asexually reproduced mass of cells, that is capable of developing into a new organism i.e., an adult sponge. Learn more about the world with our collection of regional and country maps. Sexual reproduction also occurs. The sperm and ova are also known to be derived from choanocytes which later undergo gametogenesis to form sperm or ova. See more Encyclopedia articles on: Zoology: Invertebrates. We've got you covered with our map collection. Another form of asexual reproduction that some sponges are capable of is called budding. The technique of asexual reproduction most commonly used in the production of fruit trees is _____. Most sponges are hermaphroditic, the same individual producing eggs and sperm, but in some species the sexes are separate. Study Score Infoplease knows the value of having sources you can trust. External buds are formed when fragments of a sea sponge's body are broken off by water currents and carried to other locations. google_ad_client: "ca-pub-5414192315724946", Freshwater sponges are multicellular, marine living species of a Kingdom Phylum – Porifera. Describe the formation of reduction bodies. Pieces of sponge are able to regenerate into whole new sponges. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules can withstand freezing and considerably greater degree of desiccation than the adult sponges. Asexual reproduction is when a tiny piece of an adult sponge breaks off and it becomes a new sponge. asexual reproduction in sponges. … Sexual reproduction … Gemmules are aggregates of sponge tissue and food, covered by a hard coating containing spicules or spongin fibers. How does regeneration help in sponges? When fully grown the oocyte undergoes two maturation divisions to form ovum which lies in the wall of the radial canal or spongocoel, ready to be fertilized by the sperm of other sponge. Asexual Reproduction: 'Budding' a New Generation. These gemmules are tough and coated with a dormant cluster of embryonic cells. Asexual methods of reproduction include: the growth of stolons that develop into new individuals; a bud separating from the parent sponge and creating a new sponge elsewhere; and the simple act of parts of a sponge breaking of and establishing in a new location. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules are internals buds formed within the sponge body. Not sure about the geography of the middle east? This process of asexual reproduction is found in planaria and hydra. // ]]>. ASEXUAL REPRODUCTION Regeneration All sponges possess a remarkable ability to regenerate lost parts. Role in asexual reproduction. An outgrowth from the sponge body wall may arise either at the base or near the attached end to form bud. on Apr 28, 2018 at 08:47 am. In our sponge model (Oscarella lobularis, Porifera, Homoscleromorpha) gametogenesis takes place once a year, in spring and summe r. The lashing movement of the tail helps the spermatozoon to reach other sponges. The life history of such sponges illustrates alternation of generation. The sperm and ova are derived from the undifferentiated amoebocytes called as archaeocytes. - Sponges reproduce by both asexual and sexual means. Like and Follow us on Facebook and Telegram for latest updates... // 25 Healthy Breakfast Foods, Baby Chiropractor Houston, Canon C500 Mark Ii Vs Alexa, Abolish Ice Shirt, Mina Lobata Vine, How To Cook Adzuki Beans In A Slow Cooker, Cna Resume No Experience, Turkey Shepherds Pie Frozen Vegetables, Toll House Pie Bars, Corn Plant Stalk Turning Brown, Drunk Elephant Dopp Kit Uk, How To Prevent Mold In Humid Climate, Kerastase Oleo Curl How To Use, The Knitter's Handy Book Of Patterns, Fitbit Scale Aria, "/>
Orlando, New York, Atlanta, Las Vegas, Anaheim, London, Sydney

asexual reproduction in sponges

Some fresh water and marine sponges get disintegrated during adverse conditions. In spring, when the conditions become suitable, the gemmules begin to hatch. Infoplease is a reference and learning site, combining the contents of an encyclopedia, a dictionary, an atlas and several almanacs loaded with facts. A piece cut from the body of a sponge is capable of growing into a complete sponge. Because the water moves into the sponge, we call them incurrent pores. Asexual reproduction is mainly carried out by budding and also by gemmulation. In budding, small new sponges grow from the sides of an adult sponge. With the help of external flagella, the motile larvae escapes from the parental body and swim for a few hours to many days. It either remains attached to the parent sponge or may get detached to form a new sponge by fixing itself to a suitable substratum. The asexual reproduction is commonly found in lower animals such as protozoans, sponges, coelenterates, certain worms and tunicates. Choanocytes act as nurse cells and transport the sperm to the ova which lie in the flagellated choanoderm. Unlike in sexual reproduction wherein male and female gametes unite to reproduce an offspring, in asexual reproduction… Binary Fission. The gemmules thus formed may sink to the bottom or may flow away with the water. Almost all prokaryotes undergo a type of asexual reproduction called binary fission. Another form of asexual reproduction that some sponges are capable of is called budding. Freshwater sponges, as well as several marine species, form resistant structures called gemmules that can withstand adverse conditions such as drying or cold and later … The part of parental sponge thus thrown off develops into an adult individual, breaks off an osculum at its free distal end and gets attached to a suitable substratum. In the body of an adult sponge appear lateral buds that grow and differentiate into young sponges, which separate for any or other reason, to live independently or make up a new individual of the colony. It is most commonly associated with bacteria and yeast, but some animal species reproduce via budding, too. Although sponges are bisexual (hermaphrodite) cross fertilization occurs as a rule as the production timing of sperm and ova are different. A few species can contract their whole bodies, and many can close their oscula and ostia. Freshwater sponges, as well as several marine species, form resistant structures called gemmules that can withstand adverse conditions such as drying or cold and later develop into new individuals. Sponges do not have separate sexes-a single sponge forms eggs at one time of the year and sperm at a different time. Many hydras reproduce asexually by producing buds in the body wall, which grow … Some unknown aggregation factors from the cell surface are also supposed to be necessary for the process of regeneration. Pores are also called Ostia. on May 04, 2018 at 02:09 pm. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. }); Sponges reproduce sexually to produce motile larvae or asexually by … asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult. The outer protective membrane may be strengthened by siliceous amphidisc spicules (Ephidatia) or by monaxon spicules (Spongilla). If a chunk of sponge breaks off of the whole organism, it establishes itself somewhere else and regrows into a new sponge. ... Sponge Reproduction. When sponges go through asexual reproduction, it is by a system called budding. When the favourable conditions return, each reduction body develops into a complete new sponge. This is accomplished by one of two mechanisms: external budding or internal budding. The larval stages bear flagella, which help them to escape out from the maternal sponge body. Sponge, any of the primitive multicellular aquatic animals that constitute the phylum Porifera. Sponges are in general able of both asexual and sexual reproduction. Budding is a type of asexual reproduction. Click Create Assignment to assign this modality to your LMS. Legend Boy This is caused by a cell called an archaeocyte. This process is known as regeneration. In a suitable some of these disunited cells unite to form small aggregates or spongelets. Reproduction. Their sexual reproduction is similar to higher animals even though their body organization is primitive type. Asexual reproduction is either by fragmentation (in which a piece of the sponge breaks off and develops into a new individual), or budding (an outgrowth from the parent that eventually detaches). This new individual develops a new colony by budding. Starfish, flatworms, and sponges may be cut into pieces and the individual parts will grow new individual animals by means of the process of _____. They can also reproduce via budding, where new sponges simply grow off the existing sponge. During unfavourable conditions, the sponge collapse leaving small rounded balls called as reduction bodies. Parenchymula: It is solid, oval or flattened larval stage characteristic of calcareous sponges, Hexactanellida and most Desmospongia. Sponge Larva The average sponge has a lifespan of around 20 years, but in some extreme cases, due to asexual reproduction, sponges can last up to 200 years. The internal buds, which are formed by the freshwater sponges are called gemmules. Regeneration in star fish These engulfed cells act as the nursing cells for the oocyte. If a chunk of sponge breaks off of the whole organism, it establishes itself somewhere else and regrows into a new sponge. The larvae are flagellated and swim about freely for a short time. Gemmules are set free after the decay of the parent sponge. Because the water moves into the sponge, we call them incurrent pores. Most poriferans that reproduce by sexual means are hermaphroditic and produce eggs and sperm at different times. The power of regeneration is greater in simple animals and simple tissues. Formation of gemmules Sponges are in general able of both asexual and sexual reproduction. Spore formation (sporogenesis) Spore formation or sporogenesis is a form of asexual reproduction that involves spores. Asexual reproduction is a mode of reproduction that does not entail the union of sex cells or gametes. During asexual reproduction the body (somatic) cells divide, their nucleus divides either by mitosis or amitosis, therefore, such type of reproduction is also known as somatogenic or blastogenic reproduction. Discuss the power of regeneration in sponges as experimented by Wilson, Previous years questions with explanations...for all competitive exams. Asexual reproduction occurs by budding or by fragmentation. Sperms are released out from sponge through the outgoing water from osculum. Gemmules are found in the freshwater family Spongellidae. The most frequent type of asexual reproduction is by budding. Cells from different species of sponges may adhere temporarily but later separate without re-forming a sponge. Chart the formation of buds on the sponge body. Sponges have two types of larvae. It is the characteristic feature of all fresh water and some marine forms like Ficula and Tethya. Sponges can reproduce in a variety of ways, both asexually and sexually. A matured spermatozoon consists of a rounded nucleated head and a tail. The sperms thus releases make their way into another sponge through incoming water by ostia. Like in sexual reproduction, this small piece of the sponge must find a substrate to cling to in order to grow into an adult sponge (Myers, 2001). (adsbygoogle = window.adsbygoogle || []).push({}); External budding is when a portion of the sponge breaks off and then regenerates into a complete organism. Finally they settle down, become attached to some solid object, metamorphose and grow into an adult. All animals, particularly the less specialized ones, can replace their lost or injured parts. fragmentation. Pieces of sponge are able to regenerate into whole new sponges. Phylum Porifera: Sexual and Asexual Reproduction in sponges and Regeneration in sponges. Regeneration Regeneration may be defined as the ability of an organism to grow its lost parts. Asexual Reproduction: 'Budding' a New Generation. Check our encyclopedia for a gloss on thousands of topics from biographies to the table of elements. Formation of reduction bodies 4. This is also known as fragmentation. [CDATA[ It gets attached to a suitable substratum and breaks off an osculum at its free distal end. Learn about one of the world's oldest and most popular religions. Sponges exhibit protandry, production of sperms first and ova later or protogyny, production of ova first and sperms later. // . Need a reference? They can also reproduce via budding, where new sponges simply grow off the existing sponge. Gemmules help the sponge to tide over unfavourable conditions. The regeneration power of sponges is demonstrated by the experiments carried out by Wilson in 1907. Now these spermatogonia undergo two to three maturation divisions to form spermatocytes and these spermatocytes later give rise to spermatozoa. A gemmule is a small, round, hard ball consisting of internal mass of food laden archaeocytes surrounded by chitinous double membrane. Pores are also called Ostia. ASEXUAL REPRODUCTION When reproducing asexually, sea sponges form buds which are also known as gemmules. Thus epithelial tissue regenerates readily whereas highly differentiated tissues such as muscle or nerve tissue have limited power of regeneration. Juveniles drift or swim freely, while adults are stationary. Sponges are undoubtedly the best at regeneration. Budding 2. Hypertrophy is the non-tumorous enlargement of a tissue or an organ as a result of the increase in the size rather than the number of constituent cells. The archeocyte hatches and becomes a new sponge. Asexual reproduction. Asexual reproduction does not need the pair to reproduce. ASEXUAL REPRODUCTION IN SPONGES 1. Brush up on your geography and finally learn what countries are in Eastern Europe with our maps. This spermatogonium is surrounded by one or more flattened cover cells to form spermatocyst. (adsbygoogle = window.adsbygoogle || []).push({ Sponges which have low grade of organization exhibit high degree of regeneration power. As sponges can be cut up tiny pieces or even mashed up into a paste and as long as they have two special cells called collencytes (which produce mesohyl the gelatinous matrix in the sponge that forms a sort of psuedotissue) and archeocytes (which produce all the other cells in the sponges body) the sponge will survive and reform into the spongelet and then into an adult sponge. According to the experiments conducted by Bergquist, if a tissue if grafted in a sponge from another sponge of the same species, the host and the graft will grow together. enable_page_level_ads: true asexual reproduction. According to the experiments conducted by Humphrey, calcium and magnesium ions are necessary for regeneration. Pieces of sponge are able to regenerate into whole new sponges. If a sponge is chopped into small pieces, run through a meat grinder and then squeezed through a fine blotting cloth then all the sponge cells are separated from each other. By this method the number of individuals in the colony may increase or new colonies may be formed. Amphiblastula: It is hollow, oval larval stage characteristic of calcareous sponges (Scypha). Internal budding takes place by the formation of internal buds called gemmules. The entire larva is covered by flagella. The summer generation dies off in autumn living behind gemmules which hatch in spring. Asexual reproduction occurs by budding or by fragmentation. The archaeocyte is protected until the conditions for a new sponge to develop are right. We have loaded Previous years questions with explanations...for all competitive exams. There the buds begin to grow into clones, or genetically identical sponges, of their parents. Since the reproduction is asexual, the newly created Stove Pipe Sponge is a clone and is genetically identical to the parent sponge. FEN Learning is part of Sandbox Networks, a digital learning company that operates education services and products for the 21st century. This type of reproduction is the result of the body´s fragmentation, which occurs due to exposure to unfavorable environmental conditions or as a part of the normal life cycle. sponges reproduce by asexual reproduction-budding,fragmentation; sexually by releasing sperm picked up by another sponge that amoebocytes carry to egg that develops into free-swimming ciliated larvae, larvae exits through osculum, lands and forms adult Green Finger Sponge are able to regenerate into whole new sponges. The Columbia Electronic Encyclopedia, 6th ed. Although adult sponges are fundamentally sessile animals, some marine and freshwater species can move across the sea bed at speeds of 1–4 mm (0.039–0.157 in) per day, as a result of amoeba-like movements of pinacocytes and other cells. It is very unusual method of asexual reproduction found in sponges. Gemmules are internal buds found in sponges and are involved in asexual reproduction.It is an asexually reproduced mass of cells, that is capable of developing into a new organism i.e., an adult sponge. Learn more about the world with our collection of regional and country maps. Sexual reproduction also occurs. The sperm and ova are also known to be derived from choanocytes which later undergo gametogenesis to form sperm or ova. See more Encyclopedia articles on: Zoology: Invertebrates. We've got you covered with our map collection. Another form of asexual reproduction that some sponges are capable of is called budding. The technique of asexual reproduction most commonly used in the production of fruit trees is _____. Most sponges are hermaphroditic, the same individual producing eggs and sperm, but in some species the sexes are separate. Study Score Infoplease knows the value of having sources you can trust. External buds are formed when fragments of a sea sponge's body are broken off by water currents and carried to other locations. google_ad_client: "ca-pub-5414192315724946", Freshwater sponges are multicellular, marine living species of a Kingdom Phylum – Porifera. Describe the formation of reduction bodies. Pieces of sponge are able to regenerate into whole new sponges. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules can withstand freezing and considerably greater degree of desiccation than the adult sponges. Asexual reproduction is when a tiny piece of an adult sponge breaks off and it becomes a new sponge. asexual reproduction in sponges. … Sexual reproduction … Gemmules are aggregates of sponge tissue and food, covered by a hard coating containing spicules or spongin fibers. How does regeneration help in sponges? When fully grown the oocyte undergoes two maturation divisions to form ovum which lies in the wall of the radial canal or spongocoel, ready to be fertilized by the sperm of other sponge. Asexual Reproduction: 'Budding' a New Generation. These gemmules are tough and coated with a dormant cluster of embryonic cells. Asexual methods of reproduction include: the growth of stolons that develop into new individuals; a bud separating from the parent sponge and creating a new sponge elsewhere; and the simple act of parts of a sponge breaking of and establishing in a new location. The buds may remain attached to the parent or separate from it, and each bud develops into a new individual. Gemmules are internals buds formed within the sponge body. Not sure about the geography of the middle east? This process of asexual reproduction is found in planaria and hydra. // ]]>. ASEXUAL REPRODUCTION Regeneration All sponges possess a remarkable ability to regenerate lost parts. Role in asexual reproduction. An outgrowth from the sponge body wall may arise either at the base or near the attached end to form bud. on Apr 28, 2018 at 08:47 am. In our sponge model (Oscarella lobularis, Porifera, Homoscleromorpha) gametogenesis takes place once a year, in spring and summe r. The lashing movement of the tail helps the spermatozoon to reach other sponges. The life history of such sponges illustrates alternation of generation. The sperm and ova are derived from the undifferentiated amoebocytes called as archaeocytes. - Sponges reproduce by both asexual and sexual means. Like and Follow us on Facebook and Telegram for latest updates... //

25 Healthy Breakfast Foods, Baby Chiropractor Houston, Canon C500 Mark Ii Vs Alexa, Abolish Ice Shirt, Mina Lobata Vine, How To Cook Adzuki Beans In A Slow Cooker, Cna Resume No Experience, Turkey Shepherds Pie Frozen Vegetables, Toll House Pie Bars, Corn Plant Stalk Turning Brown, Drunk Elephant Dopp Kit Uk, How To Prevent Mold In Humid Climate, Kerastase Oleo Curl How To Use, The Knitter's Handy Book Of Patterns, Fitbit Scale Aria,