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Sponge reproduction - Contenido educativo
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Se describen la reproducción asexual y sexual de las esponjas, en Inglés.
In another video we have studied sponges, and we have seen that sponges, when they are adults, do not move from place to place,
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that they have radial symmetry, this means they do not have a right and left side but are cylindrical in shape,
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and we have also studied that water is moved by special cells inside the sponge that are called quanocytes,
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and these quanocytes with the flagellum, with their tail, move the water so that
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the sponge can get food particles that are in the water. So water enters through
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the sides and exits through the top opening or osculum as we could see in a
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video. So now we're going to speak about sponge reproduction and we're going to
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see that sponges are able to reproduce asexually and sexually. So let us start
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speaking about asexual reproduction.
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Asexual reproduction in sponges usually
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happens because of fragmentation.
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Through fragmentation this means a
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sponge, as we can see in this drawing, gets
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broken. Some pieces of the sponge
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get disattached, they break. They may
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break by accident or they may break
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because the sponge itself breaks.
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So the sponge has a mechanism to break some parts of its body so that those parts of the
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body go away.
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If those parts that go away fall on a place with good nutrients, temperature, good conditions,
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etc., those species get attached and they grow and eventually they will form a new sponge.
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Of course, these new sponges that are going to form will be genetically identical to the
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parent.
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This means they will be clones of the parent sponge.
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So this is asexual reproduction.
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One individual produces clones.
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The other possibility is sponge sexual reproduction.
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In sponge sexual reproduction what is going to happen is that one sperm cell and one egg
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cell are going to fuse.
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So one sponge is going to produce many sperm cells.
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The sperm cells are actually very similar to coanocytes and they are derived from them.
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So then these sperm cells are going to swim out from one sponge and they are going to
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get inside another sponge.
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When they get inside the other sponge they will meet an egg cell.
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So fertilization is going to happen.
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Fertilization means the egg cell and the sperm cell fuse turning into one cell and that cell
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is going to divide, it is going to produce many new cells and those many new cells are
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going to form a larva.
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A larva is an individual that looks very different from the adult.
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In case of sponges the larva does not look like a sponge at all, it looks like a ball
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cells some of which have flagella okay so they have tails and with these tails
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the larva is able to swim and it is going to swim away when it finds a good
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place to live then the larva is going to transform into an adult and it is going
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to stay forever in the place that it has found okay so adults do not move larvae
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are able to swing look for a good place to live as an adult. This means sexual
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reproduction comes from the fusion of sperm and egg cells producing new
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individuals.
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- Idioma/s:
- Idioma/s subtítulos:
-
- Autor/es:
- Andrés Gaytán de Ayala Alonso
- Subido por:
- Andrés G.
- Licencia:
- Reconocimiento
- Visualizaciones:
- 161
- Fecha:
- 27 de octubre de 2020 - 16:52
- Visibilidad:
- Público
- Centro:
- IES AGORA
- Descripción ampliada:
- Para Biología de 1º ESO (sección bilingüe)
- Duración:
- 03′ 58″
- Relación de aspecto:
- 1.92:1
- Resolución:
- 1004x524 píxeles
- Tamaño:
- 6.34 MBytes
