BIS2C_Lect26_Ward_Development___Sponges_ppt

Asexual through budding or fragmentation sexual most

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Unformatted text preview: nges. Asexual: through “budding” or fragmentation Sexual: most sponges are hermaphrodites but not selffertilizing Most sponges are hermaphrodites but not self-fertilizing: sperm and eggs produced at different times (from choanocytes or other cells in the sponge body—no specialized gonads) specialized gonads). How do they reach the egg? located in mesohyl (interior) Sponge reproduction: - asexual: budding/fragmentation - sexual: hermaphrodites (produces both sperm and eggs) but not self-fertilizing (sperm and eggs are produced at different times) 7 Sexual reproduction in sponges - Sperm is captured by choanocyte (by a feeding mechanism) - However, the choanocyte loses its collar and flagellum and goes through the mesohyl as an ameboid and transports the sperm to the egg Sponge features: biology Sexual reproduction How do sponge sperm reach the egg? They need to cross the cellular barrier of choanocytes; enter the mesohyl; locate the egg; and fertilize it. Brusca & Brusca (1990): “This rather impressive feat initially involves sperm capture by choanocytes and enclosure in an intracellular vesicle (much like the formation of a food vacuole d...
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This note was uploaded on 08/07/2012 for the course BIS BIS 2C taught by Professor 3differentprofs during the Spring '09 term at UC Davis.

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