Endocrine System Quiz

False (B)

Thyroid hormones (T3 and T4)

<p>butterfly</p> Signup and view all the answers

<p>T3 = 10% of thyroid output, responsible for tissue action T4 = 90% of thyroid output</p> Signup and view all the answers

<p>Iodine (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Stimulates the secretion of thyroid releasing hormone (TRH)</p> Signup and view all the answers

<p>Epinephrine and norepinephrine (B)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Increases blood glucose levels</p> Signup and view all the answers

<p>melatonin</p> Signup and view all the answers

<p>Melatonin = Pineal gland Testosterone = Testes Insulin = Pancreas Thymosin = Thymus gland</p> Signup and view all the answers

<p>Beta cells (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Lowers blood calcium levels</p> Signup and view all the answers

<p>Increases basal metabolic rate (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Hyperthyroidism</p> Signup and view all the answers

<p>aldosterone</p> Signup and view all the answers

<p>Cortisol = Glucose formation under stress Calcitonin = Lowers blood calcium levels Parathyroid Hormone = Increases blood calcium levels Aldosterone = Regulates sodium and water reabsorption</p> Signup and view all the answers

<p>Weight gain (A)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Increased nerve excitability</p> Signup and view all the answers

<p>Adrenal</p> Signup and view all the answers

<p>Addison’s disease (B)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>Increase glucose formation</p> Signup and view all the answers

<p>calcium</p> Signup and view all the answers

<p>High blood calcium levels (D)</p> Signup and view all the answers

<p>Cushing’s syndrome = Hypersecretion of glucocorticoids Addison’s disease = Hyposecretion of glucocorticoids and aldosterone Hyperthyroidism = Excessive thyroid hormone production Hypothyroidism = Insufficient thyroid hormone production</p> Signup and view all the answers

The thyroid gland is a butterfly-shaped organ located below the larynx and in front of the trachea. It has two lobes connected by a bridge-like isthmus.

The thyroid gland is made up of tiny structures called thyroid follicles. The walls of these follicles contain two types of cells: follicular cells and parafollicular cells.

Follicular cells are responsible for producing thyroid hormones, which regulate metabolism. Parafollicular cells produce calcitonin, a hormone that helps regulate calcium levels in the blood.

Thyroid hormones are synthesized from iodine and tyrosine. They are stored within the thyroid follicles as colloid and can sustain the body's needs for 1-3 months.

Thyroid hormones are transported in the blood by plasma proteins.

Low blood levels of thyroid hormones or a low metabolic rate trigger the hypothalamus to release thyroid-releasing hormone (TRH).

TRH stimulates the anterior pituitary gland to release thyroid-stimulating hormone (TSH).

TSH stimulates the thyroid follicular cells to produce and release thyroid hormones. It also promotes the growth of these cells.

The adrenal medulla, an inner part of the adrenal gland, secretes two hormones - epinephrine (adrenaline) and norepinephrine. These hormones have effects similar to the sympathetic nervous system, essentially preparing the body for a 'fight or flight' response.

Epinephrine, also known as adrenaline, is a hormone secreted by the adrenal medulla in response to stress. It plays a critical role in the fight-or-flight response, increasing heart rate, blood pressure, and blood sugar levels.

The pancreas is a gland located behind the stomach. It functions as both an endocrine and exocrine gland.

The pancreas contains clusters of hormone-secreting cells called pancreatic islets (islets of Langerhans). These islets contain alpha cells(A) and beta cells (B).

Alpha cells in the pancreas secrete glucagon, a hormone that increases blood glucose levels by promoting the breakdown of glycogen into glucose.

Beta cells in the pancreas secrete insulin, a hormone that decreases blood glucose levels by promoting the uptake of glucose from the blood into cells.

The ovaries, female reproductive organs, produce three main hormones: estrogens, progesterone, and inhibin. These hormones regulate the menstrual cycle, maintain pregnancy, prepare the mammary glands for lactation, and establish and maintain female secondary sex characteristics.

The testes, the male reproductive organs, produce testosterone, an androgen hormone. Testosterone plays a crucial role in regulating sperm production, promoting development, and maintaining male secondary sex characteristics.

A condition where the thyroid gland is enlarged and produces excessive thyroid hormones leading to a high metabolic rate, hyperactivity, insomnia, nervousness, irritability, and chronic fatigue.

A state of deficiency or lack of thyroid hormones. In infants, it can cause cretinism, a condition characterized by mental retardation and abnormal skeletal features. In adults, it can lead to myxedema, with symptoms like slow heart rate, low body temperature, sensitivity to cold, dry hair and skin, muscular weakness, general lethargy, and weight gain.

A hormone secreted by the parafollicular cells or C cells in the thyroid gland. It inhibits osteoclast activity, lowering the blood level of calcium. Its secretion is controlled by calcium levels in the blood.

Small glands embedded on the posterior surfaces of the lateral lobes of the thyroid gland. Each thyroid lobe has two parathyroid glands attached to it.

The major hormone produced by the parathyroid glands, responsible for regulating calcium, magnesium, and phosphate levels in the blood. It increases osteoclast activity, promotes reabsorption of calcium from the urine, and inhibits phosphate reabsorption, leading to more phosphate excretion.

A condition caused by insufficient secretion of parathyroid hormone (PTH), leading to low blood calcium levels and increased nerve excitability, resulting in spontaneous muscle contractions.

A condition caused by excessive secretion of parathyroid hormone (PTH) due to a tumor in the thyroid gland. It increases osteoclast activity, removes calcium from the bones, and raises blood calcium levels. Excess calcium can cause kidney stones.

Two glands, one superior to each kidney, consisting of an adrenal cortex (outer) and adrenal medulla (inner).

The outer layer of the adrenal gland, subdivided into three zones: zona glomerulosa, zona fasciculata, and zona reticularis, each producing different steroid hormones.

Hormones produced by the zona glomerulosa of the adrenal cortex. The major mineralocorticoid is aldosterone, which regulates blood pressure and volume by increasing sodium and water reabsorption, decreasing potassium reabsorption, and promoting hydrogen ion excretion.

Hormones produced by the zona fasciculata of the adrenal cortex. The primary glucocorticoid is cortisol, which regulates glucose metabolism, increases protein breakdown, stimulates triglyceride breakdown, has anti-inflammatory effects, and suppresses immune response.

Hormones produced by the zona reticularis of the adrenal cortex. They have masculinizing sex hormone effects but have minimal effects in men, playing a role in libido in women.

A condition caused by hypersecretion of hormones from the adrenal cortex, characterized by hyperglycemia, puffiness or edema, and loss of potassium ions.

A condition caused by hyposecretion of glucocorticoids and aldosterone from the adrenal cortex, leading to hypoglycemia, sodium loss, low blood pressure, dehydration, and muscle weakness.