Praktikum Histologi - Sistem Endokrin

Summary

In this video, the speaker introduces the endocrine system, explaining the structure and function of various glands, such as the adrenal glands, thyroid, parathyroid, pituitary, and pancreas. Each gland's role in hormone production is explored in detail, from the adrenal cortex and medulla to the thyroid’s follicular structure and parathyroid’s principal cells. The pituitary's anterior and posterior divisions are also discussed, alongside the pancreatic islets, highlighting the hormones involved in regulating bodily functions like metabolism and calcium levels. The session concludes with a practical drawing activity to help students visualize the glandular structures.

Takeaways

• 😀 The adrenal gland (suprarenal gland) is located above the kidneys and consists of two main components: the outer cortex and the inner medulla.
• 😀 The cortex of the adrenal gland is divided into three zones: the zona glomerulosa (produces mineralocorticoids), the zona fasciculata (produces glucocorticoids and adrenal androgens), and the zona reticularis (produces glucocorticoids and adrenal androgens).
• 😀 The adrenal medulla has clear cytoplasm and plays a role in producing hormones like adrenaline and noradrenaline.
• 😀 The thyroid gland is located in the front of the neck and contains follicles that store colloid material (thyroglobulin) for the production of thyroid hormones.
• 😀 The parathyroid glands, located behind the thyroid, consist of principal (chief) cells and oxyphil cells. The principal cells produce parathyroid hormone (PTH), which regulates blood calcium levels.
• 😀 The pituitary gland controls the endocrine system, with the anterior pituitary (adenohypophysis) composed of chromophobes and chromophils (acidophils and basophils) that produce various hormones.
• 😀 The pancreas contains both exocrine and endocrine components. The endocrine component, known as the islets of Langerhans, consists of alpha cells (which produce glucagon), beta cells (which produce insulin), and delta cells (which produce somatostatin).
• 😀 The function of the alpha cells in the pancreas is to raise blood glucose levels by producing glucagon, while the beta cells lower blood glucose by producing insulin.
• 😀 Delta cells in the pancreas help balance the actions of the alpha and beta cells and also produce somatostatin, which regulates growth hormone and insulin release.
• 😀 The script explains how various endocrine glands play a crucial role in hormone regulation and maintaining homeostasis within the body.

Q & A

What is the location and structure of the suprarenal gland?

The suprarenal gland, also known as the adrenal gland, is located above the kidneys. Its structure resembles a cap placed on top of the kidneys and is divided into two main components: the cortex (outer part) and the medulla (inner part).

What are the three main zones of the adrenal cortex and their functions?

The adrenal cortex is divided into three zones: 1) The zona glomerulosa, which produces mineralocorticoids; 2) The zona fasciculata, which produces glucocorticoids and adrenal androgens; 3) The zona reticularis, which also produces glucocorticoids and adrenal androgens.

What is the function of the zona glomerulosa in the adrenal cortex?

The zona glomerulosa produces mineralocorticoids, which play a role in regulating sodium and potassium balance in the body.

What hormone does the zona fasciculata of the adrenal cortex produce?

The zona fasciculata produces glucocorticoids and adrenal androgens, which help regulate metabolism and contribute to the stress response.

What is the function of the adrenal medulla?

The adrenal medulla produces catecholamines, primarily adrenaline (epinephrine) and norepinephrine, which are involved in the body's fight-or-flight response.

What is the structure and function of the thyroid gland?

The thyroid gland is located at the front of the neck. It consists of follicular structures that contain colloid material, which stores thyroglobulin. The thyroid's primary function is to produce thyroid hormones (T3 and T4) that regulate metabolism.

What are the two types of cells found in the parathyroid gland and their roles?

The parathyroid gland contains two types of cells: principal (chief) cells, which produce parathyroid hormone (PTH) to regulate calcium levels in the blood, and oxyphil cells, whose exact function is unclear but are believed to be a variant of principal cells.

How does parathyroid hormone (PTH) function in the body?

Parathyroid hormone (PTH) regulates the calcium levels in the blood by increasing calcium release from bones, enhancing calcium reabsorption in the kidneys, and promoting the activation of vitamin D, which increases calcium absorption in the intestines.

What are the components of the pituitary gland and their functions?

The pituitary gland consists of the anterior pituitary (adenohypophysis) and posterior pituitary (neurohypophysis). The anterior pituitary produces several hormones that regulate other endocrine glands, while the posterior pituitary stores and releases hormones like oxytocin and vasopressin.

What is the structure and function of the pancreas in terms of endocrine activity?

The pancreas contains both exocrine and endocrine components. The endocrine part consists of islets of Langerhans, which include alpha cells (producing glucagon), beta cells (producing insulin), and delta cells (producing somatostatin), all involved in regulating blood glucose levels.