Although most bacteria are harmless or often beneficial, several are pathogenic. One of the bacterial diseases with the highest disease burden is tuberculosis, caused by the bacterium Mycobacterium tuberculosis, which kills about 2 million people a year, mostly in sub-Saharan Africa.athogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter, and Salmonella.
exists and is an alternate of . The brooms are used to sweep the ice in front of a sliding rock. The friction created from sweeping melts the ice just a tiny bit, enough to decrease the friction between the rock and the ice, making the rock both slide farther and slide straighter (curl less).
By building an ice rink, more than just the. game of ice hockey prospers. In many communi-. ties, the ice rink has become the centre of social life. where many other activities can be performed. An. ice rink can also be used for figure skating, fairs, ex-. hibitions, minor conventions and coaching clinics.