Annelids-In earthworms, respiration is through the skin, but gills are used to exchange oxygen and and carbon dioxide in other types of annelids. Arthropoda-Some arthropods have gills and some have a tracheal system to obtain oxygen and then get rid of carbon dioxide.nnelids-In earthworms, respiration is through the skin, but gills are used to exchange oxygen and and carbon dioxide in other types of annelids. Arthropoda-Some arthropods have gills and some have a tracheal system to obtain oxygen and then get rid of carbon dioxide.
Cistus, with its many hybrids and cultivars, is commonly encountered as a garden flower. The common name rockrose is applied to the species, a name also shared by the related genera Halimium, Helianthemum and Tuberaria, all in the family Cistaceae. The common name gum cistus is applied to resin-bearing species, especially C. ladanifer.
White rock sugar. Rock candy (also called rock sugar) is a type of confection composed of relatively large sugar crystals. This candy is formed by allowing a supersaturated solution of sugar and water to crystallize onto a surface suitable for crystal nucleation, such as a string, stick, or plain granulated sugar.