Introduction of sponges

Sponges 

 1. Sponges are marine animals that live in a widely diverse range of ocean habitats, with some making poisons to keep other fauna from growing on them or to allow their own spreading growth.

2. Most live in quiet, clear waters, because sediment stirred up by waves or currents would block their pores, making it difficult for them to feed and breathe.[2] The greatest numbers of sponges are usually found on firm surfaces such as rocks, but some sponges can attach themselves to soft sediment by means of a root-like base.

3. their very porous construction enables them to extract food from these resource-poor waters with the minimum of effort.

4.Many sponges shed spicules, forming a dense carpet several meters deep that keeps away echinoderms which would otherwise prey on the sponges.[1] They also produce toxins that prevent other sessile organisms such as bryozoans or sea squirts from growing on or near them, making sponges very effective competitors for living space.Glass sponges produce no toxic chemicals, and live in very deep water where predators are rare.

Collaboration with other organisms

In addition to hosting photosynthesizing endosymbionts,[7] sponges are noted for their wide range of collaborations with other organisms. The relatively large encrusting sponge Lissodendoryx colombiensis is most common on rocky surfaces, but has extended its range into seagrass meadows by letting itself be surrounded or overgrown by seagrass sponges, which are distasteful to the local starfish and therefore protect Lissodendoryx against them; in return the seagrass sponges get higher positions away from the sea-floor sediment.[

body of sponge forms a wall around a hollow cavity

body has openings or pores which water moves through

water propelled by flagella (collar cells)

water delivers food and oxygen to the cells and removes wastes out the top opening (osculum).gametes are transported through the water.

spiney spicules interlock forming the skeleton

amebocytes produce spicules from calcium carbonate or silica

softer sponges are made up of a protein called sponging

are filter feeders

ameobocytes digest food

digestion is intracellular

chemical defenses.4)All are sessile, (live attached to something as an adult). Throughout this body run canals through which water flows, there is considerable variation in the complexity of these canals. The canals have openings to the outside which are called pores, where the water enters the sponge system these pores are usually small and are called 'ostia' and where the water leaves the sponge system the pores are larger, often singular and are called 'oscula' (singular osculum). Many if not most of these canals are lined with special flagellated cells called 'choanocytes'

. These choanocytes keep the water flowing through the canals in the correct direction by beating their flagellum, they are also important in trapping food items.

The fertilised ova are retained within the adult sponge until some unknown signal indicates it is time for their release. They are then set free into the surrounding waters.

Sponges are strong animals with dense skeletons that are well adapted to their environments. As they may live almost everywhere, they adapt to the regions and surfaces they grow in. Certain sponge species are adapted to freshwater environments. Their skeleton types allow them to live in either hard or soft sediments. Their pores allow them to filter the water around them for food. Inside the sponge, there are flagella that create currents so their collar cells may trap the food. Sponges may have adapted to these feeding habits from a long time ago when food sources may have been scarce.

Sponges have strong structures that are able to handle the high volume of water that flows through them each day. By constricting certain of their openings, sponges are able to control the amount of water that flows through them. Scientists believe that sponges are colourful because the colours act as a protection from the sun’s harmful UV rays.

Sponges have been around for a very long time.  This is because although the world is constantly changing, sponges are still able to respond to these changes through adapting to their environment. Sponges are also able to release toxic substances into the environment around them to make sure they have a good place to grow in.