Where the cancer starts is called the primary tumour. Some types of cancer, called leukaemia, start from blood cells. They don't form solid tumours. Instead, the cancer cells build up in the blood and sometimes the bone marrow. For a cancer to start, certain changes take place within the genes of a cell or a group of cells.
pommel horse. n. 1. A piece of gymnastic equipment that consists of a padded, loaf-shaped object with two pommels on top and stands horizontal to the floor, usually on adjustable legs. 2. An athletic event in which the pommel horse is used.
The Pony of the Americas is an ideal riding horse for children due to its small stature, athleticism, and gentle personality. For young equestrian riders, who are too big for the smaller ponies yet not quite ready for a full sized horse, the Pony of the Americas is a perfect match. The growing popularity of the Pony of the Americas lends itself to being a breed for children to ride and show. It is a pony breed with a good appearance, speed, and stamina.