Why are some patients of diabetes treated by giving injections of insulin?
Some patients of diabetes are treated by giving injections of insulin because their pancreas does not secrete this hormone in proper amounts. Insulin is a hormone produced by the pancreas which is responsible for regulating blood sugar levels.
If insulin is not secreted adequately, the sugar level in the blood rises. This rise in blood sugar causes many harmful effects in the body. Therefore, to control the blood sugar levels and prevent these harmful effects, insulin is provided externally through injections.
Explanation
The answer is derived directly from the textbook context which explains that insulin regulates blood sugar levels. The text states that if insulin 'is not secreted in proper amounts, the sugar level in the blood rises causing many harmful effects.' Consequently, patients take injections of insulin as a treatment to manage this regulation.