In your body, you have only two types of bone tissue: cortical and cancellous bone. In this lesson, we will learn about the structure and function of cancellous bone, which plays a crucial role in producing blood cells and stem cells and is the primary tissue affected by osteoporosis.
balaclava (plural balaclavas) 1  A warm cap shielding the neck and head, often made out of wool. ( 2 chiefly Canada) A ski mask with holes for the eyes and, sometimes, the nose and mouth, which may be rolled up and worn like a toque or pulled over the face for greater protection.
The name comes from their use at the Battle of Balaclava during the Crimean War, referring to a town near Sevastopol in Crimea.ritish Police in Kent confiscated the War on Terror board game partly because of the inclusion of a balaclava. Police said it could be used to conceal someone's identity or could be used in the course of a criminal act.