30 Questions
The thyroid gland is composed of four lobes.
False
The principal cells in the thyroid gland produce thyroid hormones.
False
Graves' disease is a rare autoimmune disease that affects men.
False
Thyroiditis is an acute inflammation of the thyroid gland.
False
Endemic goiter is caused by excessive iodine intake.
False
The parathyroid glands are located within the adrenal glands.
False
The adrenal cortex makes up 15% of the cortical volume.
False
The adrenal medulla produces hormones that regulate water and electrolyte balance.
False
Addison's disease is caused by an overactive adrenal gland.
False
APUD cells are found only in the thyroid gland.
False
The endocrine system excludes the pituitary gland.
False
Hormones are proteins and glycoproteins only.
False
Autocrine communication involves a cell stimulating its neighbor.
False
The pituitary gland is approximately 5 cm in diameter.
False
The adenohypophysis cerebri has only two components.
False
Somatotrophs produce oxytocin.
False
Undersecretion of growth hormone in childhood leads to acromegaly.
False
The pars intermedia is a remnant of Rathe's pouch and mainly consists of active secretory cells.
False
The hypothalamus is a large area in the brain.
False
The infundibulum is a part of the hypothalamus.
False
The hypothalamus is located in the brain, between the pituitary gland and the cerebellum.
False
The hypothalamus plays no role in regulating body temperature.
False
The supraoptic nucleus is a part of the hypothalamus.
True
The pars nervosa contains secretory or neuronal cells.
False
Herring bodies are found in the pars nervosa.
True
The pineal gland weighs approximately 1 kg.
False
Pinealocytes are glial-like cells.
False
The thyroid gland is located in the brain.
False
The hypothalamus is not involved in the regulation of emotions.
False
The hypothalamus is responsible for maintaining homeostasis in the body.
True
Study Notes
Thyroid Gland
- Built with two lobes connected by a necking
- Composed of follicles, colloid, blood vessels, and parafollicular cells (C cells)
- Function: Synthesis of thyroid hormones (T4 and T3)
- T3: triiodothyronine
- T4: thyroxine
Thyroid Hormones
- Produced by principal cells (clear cells)
- Regulated by parafollicular cells (C cells)
Thyroid Disorders
- Graves' disease: autoimmune disease, 80-90% of all hyperthyroidism, mostly affects women
- Thyroiditis: inflammation of the thyroid, mostly chronic-autoimmune, presents as goiter
- Endemic goiter: enlargement of the thyroid gland due to iodine deficiency in the diet
Parathyroid Gland
- Composed of oxyphil cells and principal (chief) cells
- Function: regulates water and electrolyte balance
Adrenal Gland
- Weight: approximately 18g (adrenal cortex) and 4g (adrenal medulla)
- Composed of adrenal cortex (95% of the gland) and adrenal medulla (5%)
- Adrenal cortex: divided into three zones - zona glomerulosa, zona fasciculata, and zona reticularis
- Function: regulates water and electrolyte balance
Endocrine System
- Includes endocrine glands and their hormones
- Function: secretes hormones into the bloodstream to regulate various bodily functions
- Hormones: chemical messengers that target specific groups of cells to stimulate or inhibit activity
Endocrine Glands
- Locations: pituitary gland, thyroid gland, parathyroid gland, adrenal gland, pineal gland, and others
- Hormones: proteins, glycoproteins, small peptides, amino-acid derivatives, and steroids
Communication Pathways
- Autocrine: cell produces hormone that stimulates or inhibits itself
- Paracrine: cell produces hormone that stimulates or inhibits its neighbor
- Juxtacrine: cells sit side by side, one has hormone on its surface, the other has the receptor
Pituitary Gland
- Weight: approximately 0.5-1g
- Diameter: approximately 1 cm
- Components: adenohypophysis (anterior lobe) and neurohypophysis (posterior lobe)
Pituitary Gland Cells
- Chromophils: acidophils and basophils
- Chromophobes: non-staining cells
- Adenohypophysis: produces hormones that regulate various bodily functions
- Neurohypophysis: stores and releases hormones produced by the hypothalamus
Pituitary Hormones
- Growth hormone (GH): regulates growth and development
- Oversecretion: gigantism in childhood and acromegaly in adulthood
- Undersecretion: dwarfism in childhood
Hypothalamus
- Weight: approximately 0.7g
- Diameter: approximately 1 cm
- Location: center of the brain, between the pituitary gland and thalamus
- Function: regulates hormone production, body temperature, thirst, appetite, emotions, sleep cycles, sex drive, and other bodily functions
- Acts as the connector between the endocrine and nervous systems
Pineal Gland
- Weight: approximately 0.2g
- Length: 5-8 mm
- Width: 3-5 mm
- Composed of pinealocytes, interstitial glial cells, and corpus arenaceum (brain sand)
- Function: regulates sleep-wake cycles and reproductive hormones
This quiz covers the structure and function of the thyroid gland, including its lobes, neck, and cells, as well as its role in synthesizing thyroid hormones. It also touches on related diseases such as Graves' disease.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
