A newly diagnosed patient asks the nurse to explain asthma. Which of the following explanations by the nurse is correct?

A. Asthma is a chronic respiratory condition characterized by inflammation and hyperresponsiveness of the airways. This inflammation leads to bronchoconstriction, causing symptoms like wheezing, shortness of breath, chest tightness, and coughing. This description accurately captures the primary pathological features of asthma.
B. Fluid in the lungs, also known as pulmonary edema, is not a characteristic of asthma. Pulmonary edema is usually associated with conditions such as heart failure or acute respiratory distress syndrome (ARDS), not asthma.
C. Airway stretching and nonfunctionality are not characteristics of asthma. Conditions like bronchiectasis involve permanent dilation and damage to the airways, leading to chronic infections and impaired clearance of mucus, but this is different from asthma.
D. Asthma is not primarily caused by an infection, although infections can trigger asthma exacerbations. The primary issue in asthma is chronic inflammation and hyperresponsiveness of the airways, which are not caused by a low-grade infection but by a combination of genetic and environmental factors.

B. Beta cells are the pancreatic cells responsible for secreting insulin. Insulin acts to lower blood sugar levels by facilitating the uptake of glucose into cells for energy or storage. In individuals with diabetes mellitus, dysfunction of beta cells can lead to inadequate insulin secretion, resulting in high blood sugar levels.
A. Alpha cells are another type of cell in the pancreas, but they secrete glucagon, not insulin. Glucagon has the opposite effect of insulin, increasing blood sugar levels by stimulating the breakdown of glycogen in the liver.
C. Acinar cells are exocrine cells found in the pancreas that secrete digestive enzymes into the pancreatic ducts. These enzymes aid in the digestion of food in the small intestine. Acinar cells are not involved in the production of insulin.
D. Plasma cells are a type of white blood cell that produces antibodies as part of the immune response. They are not involved in the production of insulin.