تمرين وصف آلية عمل هرمون الإنسولين - كتاب أنظمة جسم الإنسان - الصف 12 - الفصل 1 - المملكة العربية السعودية

--- SECTION: 3 --- السؤال الثالث: مستعيناً بالشكل أدناه صف طريقة عمل هرمون الإنسولين. --- SECTION: Page Footer --- 235 وزارة التعليم Ministry of Education 2023 - 1447 --- VISUAL CONTEXT --- **DIAGRAM**: طريقة عمل هرمون الإنسولين Description: The diagram shows two distinct states of a cell membrane, depicting the interaction of insulin and glucose. The overall process illustrates how insulin enables glucose entry into a cell. **Left Panel (Before Insulin Action):** This panel shows a cell membrane with two types of structures on its surface and molecules outside the cell: - **مستقبلات الإنسولين (Insulin Receptors):** Depicted as a light blue, U-shaped structure embedded in the cell membrane, positioned towards the left side of the cell's top surface. - **قناة الجلوكوز (مغلقة) (Glucose Channel (Closed)):** Depicted as a green, circular structure embedded in the cell membrane, positioned towards the right side of the cell's top surface. A label explicitly states it is 'مغلقة' (closed). - **الجلوكوز (Glucose):** A single red, spherical molecule shown floating above the cell, slightly to the left of the closed glucose channel. - **الإنسولين (Insulin):** A single yellow, mushroom-shaped molecule shown floating above the cell, slightly to the left of the glucose molecule and above the insulin receptors. In this state, the insulin molecule is not bound to its receptor, and the glucose channel remains closed, preventing glucose from entering the cell. **Right Panel (After Insulin Action):** This panel shows the same cell membrane after insulin has acted: - **مستقبلات الإنسولين (Insulin Receptors):** The light blue, U-shaped insulin receptor now has the yellow, mushroom-shaped **الإنسولين (Insulin)** molecule bound to it. The insulin molecule is shown fitting into the receptor. - **قناة الجلوكوز مفتوحة (Glucose Channel Open):** The green, circular glucose channel is now depicted with a wider, open aperture, indicating it has changed conformation. A label explicitly states it is 'مفتوحة' (open). - **الجلوكوز (Glucose):** Multiple red, spherical glucose molecules are shown actively moving through the now-open glucose channel, from outside the cell to the inside. Some glucose molecules are shown outside the cell, one is passing through the channel, and one is already inside the cell. This state illustrates that the binding of insulin to its receptor triggers the opening of the glucose channel, allowing glucose to enter the cell. X-axis: Not applicable Y-axis: Not applicable Data: This diagram illustrates a sequential biological process rather than numerical data. It shows the transition from an inactive state (closed glucose channel) to an active state (open glucose channel) mediated by insulin binding. Context: This visual element is crucial for understanding the mechanism of insulin, a key hormone in regulating blood glucose levels. It demonstrates how insulin acts as a ligand to its receptor, leading to a conformational change in the glucose channel, thereby facilitating glucose transport into cells. This is a fundamental concept in endocrinology and metabolism.