Final answer:
A doctor advised insulin injections because the person's blood sugar level was high. Insulin lowers glucose levels by aiding its uptake into cells, which is crucial for individuals with diabetes to prevent complications such as heart and kidney disease.
Step-by-step explanation:
A doctor would likely advise a person to take an injection of insulin if (d) his sugar level in blood was high. Insulin is a hormone that is produced by the pancreas in response to increased blood glucose levels. Its role is to facilitate the transport and storage of glucose into cells, which lowers blood glucose levels and prevents hyperglycemia.
People with diabetes, such as type 1 or insulin-dependent type 2, often require insulin injections to manage their condition. Because their pancreas either does not produce enough insulin or their cells are resistant, supplemental insulin helps maintain blood glucose levels within a normal range. This is crucial as consistently high blood sugar can lead to serious complications including heart disease, and kidney disease.
Insulin injections are part of a negative feedback loop that helps to regulate blood glucose production. When blood sugar levels rise after a meal, insulin helps bring the levels down to normal by allowing glucose to be used for energy or stored for later use. In the absence of sufficient insulin, blood sugar levels remain elevated, leading to the symptoms and complications associated with diabetes.