What is somatic embryogenesis in sponges?

The somatic embryogenesis represents the most profound regenerative process in metazoans, occurring only after deep disintegration of the normal tissue organization, loss of polarity, and symmetry in regenerating fragment [1,23,24].

What is the reproduction and fertilization of sponges?

Sponges may also reproduce asexually. Sperm are released into the surrounding water through the osculum. If they enter a female sponge through a pore, they may be trapped by collar cells. Trapped sperm are delivered to eggs inside the female body, where fertilization takes place.

What is the embryonic development of sponges?

Formation of embryonic layers in sponges has historically been attributed to a range of gastrulation processes, including epiboly, delamination and ingression, some of which require coordinated movement of sheets of cells (reviewed in Leys, 2004).

What is the process of sponges reproduction?

Summary. Sponges are able to reproduce both sexually using gametes and asexually by budding. Even though sponges are hermaphroditic, individuals will only make one type of gamete at a time. There are two forms of asexual reproduction that sponges can go through: external budding and internal budding.

What is meant by somatic embryogenesis?

Somatic embryogenesis is a developmental process where a plant somatic cell can dedifferentiate to a totipotent embryonic stem cell that has the ability to give rise to an embryo under appropriate conditions. This new embryo can further develop into a whole plant.

What is direct and indirect somatic embryogenesis?

Direct somatic embryogenesis occurs when embryos are started directly from explant tissues (pre- embryogenic cells) creating an identical clone, while indirect somatic embryogenesis occurs from unorga- nized tissues (calli) which are further developed into embryos (Nakamura et al. 1992; Calheiros et al. 1994).

Do sponges have internal or external fertilization?

Reproduction: Most sponges are hermaphrodites (each adult can act as either the female or the male in reproduction). Fertilization is internal in most species; some released sperm randomly float to another sponge with the water current.

Which type of fertilization is found in sponges?

Although these sponges are hermaphrodite, self-fertilization usually does not occur in them as male and female gamete mature at different times. They possess cross-fertilization, They have a characteristics cell called choanocytes (collar cell) lining their inner portion of the body.

Do sponges have indirect development?

The eggs hatch to produce larvae(indirect development). The larvae are like balls of cells which have cilia and flagella for movement.

What sponges can tell us about the evolution of developmental processes?

It is known that the developmental toolkit of sponges includes signalling pathways, transcription factors and cell adhesion molecules that are employed during development of more complex animals (i.e. bilaterians).

What is somatic embryogenesis and its importance?

Somatic embryogenesis is an artificial process in which a plant or embryo is derived from a single somatic cell. Somatic embryos are formed from plant cells that are not normally involved in the development of embryos, i.e. ordinary plant tissue. No endosperm or seed coat is formed around a somatic embryo.