Who discovered insulin, the hormone used to control blood sugar levels and treat diabetes mellitus?

Introduction / Context:

Insulin is a vital hormone that allows the body to regulate blood glucose levels. Its discovery transformed the treatment of diabetes from a fatal condition to a manageable chronic disease. This question asks you to identify the scientist who is most strongly associated with the discovery of insulin and its first successful use as a therapy in humans.

Given Data / Assumptions:

• The substance in question is insulin, used in diabetes treatment.
• The question focuses on the discovery of insulin as a hormone and therapy.
• The options list several famous scientists who made important medical discoveries.
• Your task is to link the correct scientist with insulin, not with antibiotics or other substances.

Concept / Approach:

Frederick Banting, a Canadian physician, is credited with the discovery of insulin along with his colleague Charles Best. In the early 1920s they extracted insulin from pancreatic tissue and demonstrated that it could lower blood sugar in diabetic dogs and later in human patients. This discovery led to a dramatic improvement in survival and quality of life for people with diabetes. Banting received the Nobel Prize in Physiology or Medicine for this work. The other scientists listed are linked with different discoveries such as penicillin, vitamins and germ theory, not specifically with insulin.

Step-by-Step Solution:

Verification / Alternative check:

Biology and medical textbooks consistently state that insulin was discovered in the early 1920s by Banting, working at the University of Toronto. They often include photographs of early insulin vials and stories of the first children with diabetes whose lives were saved by insulin injections. These accounts confirm Banting as the central figure in insulin discovery, distinct from Fleming or Pasteur, who are mentioned in chapters on antibiotics and germs.

Why Other Options Are Wrong:

Sir Alexander Fleming discovered penicillin, an antibiotic used to treat bacterial infections, not insulin.

James Watt is an engineer known for improving the steam engine and has no connection with hormone discovery.

Sir F. G. Hopkins contributed to the discovery of vitamins and essential dietary factors, not specifically to insulin.

Louis Pasteur worked on germ theory and vaccines for diseases like rabies, but did not isolate insulin.

Common Pitfalls:

Because all the listed names are famous, students sometimes choose based on general fame instead of matching the specific discovery. To avoid this, make clear pairs in your memory, such as Fleming penicillin, Banting insulin, Pasteur rabies and germ theory. When you see a question about diabetes and blood sugar regulation, the name Banting should immediately come to mind.

Final Answer:

Insulin was discovered by Frederick Banting.