REMOVING floor-to-ceiling walls at the top of a stairway can turn an upstairs hallway or room into a light and airy landing and also bring increased light and openness to the stairwell. For safety, the floor surrounding the stairway must be partly enclosed. One solution is to install a railing around the opening.
A sponge is a member of the phylum Porifera. It is a simple animal with many cells, but no mouth, muscles, heart or brain. It is sessile: it cannot move from place to place the way most other animals can. A sponge is an animal that grows in one spot like most plants do.Nevertheless, sponges are quite successful. sponge is a member of the phylum Porifera. It is a simple animal with many cells, but no mouth, muscles, heart or brain. It is sessile: it cannot move from place to place the way most other animals can. A sponge is an animal that grows in one spot like most plants do. Nevertheless, sponges are quite successful.
sponges are the simplest form of multi cellular animals they are very diverse and come in a large variety of colours shapes and structural complexities they range in heights of 1 200cm and in diameters of 1 150cmthey have partially differentiated tissues and not true tissuessponges don t have internal organsthey don t have muscles a nervous system or a circulatory system their walls are lined with many small pores called ostia that allow water flow into the sponge the structure of a sponge is simpleone end is attached to a solid such as a rock while the other end called the osculum is open to the environment sponges are able to get microorganisms such as algae and bacteria for food through openingshe structure of a sponge is simple one end is attached to a solid such as a rock while the other end called the osculum is open to the environment sponges are able to get microorganisms such as algae and bacteria for food through openings