1What is a gland?
A group of epithelial cells that produce secretions
2What is the difference between endocrine and exocrine glands?
Endocrine glands release hormones into the blood, while exocrine glands secrete through ducts onto specific tissues
3What is the function of the endocrine system?
To regulate cell growth, metabolism, and maintain homeostasis through hormone release
4How do steroid hormones act on cells?
They diffuse into cells, bind to DNA in the nucleus, and regulate gene expression
5What are examples of steroid hormones?
Glucocorticoids and mineralocorticoids
6What is the primary function of non-steroid hormones?
They act as "first messengers," triggering "second messengers" in the cell
7Which hormones are controlled by the hypothalamus and pituitary gland?
Growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), prolactin (PRL), follicle-stimulating hormone (FSH), luteinizing hormone (LH), oxytocin, and antidiuretic hormone (ADH)
8Where is the thyroid gland located?
In the neck, at the level of the 5th, 6th, and 7th cervical vertebrae and the 1st thoracic vertebra
9What are the main hormones produced by the thyroid gland?
T3 (triiodothyronine) and T4 (thyroxine)
10What is hypothyroidism?
A condition caused by low T3 and T4 levels, leading to a decreased metabolic rate
11What is hyperthyroidism?
A condition caused by excessive T3 and T4, leading to an increased metabolic rate
12What are common symptoms of hyperthyroidism?
Increased metabolic rate, weight loss, anxiety, tachycardia, and heat intolerance
13What are common symptoms of hypothyroidism?
Decreased metabolic rate, weight gain, lethargy, bradycardia, and cold intolerance
14What hormones are produced by the adrenal cortex?
Corticosteroids, including glucocorticoids and mineralocorticoids
15What does the adrenal medulla secrete?
Adrenaline and noradrenaline, which enhance the fight-or-flight response
16What is the function of insulin?
To lower blood glucose by promoting its uptake and storage
17Where is insulin produced?
In the pancreatic beta cells
18What is the function of glucagon?
To raise blood glucose by stimulating glycogen breakdown and glucose production in the liver
19What triggers the release of glucagon?
Low blood glucose levels
20What role does the pancreas play in blood glucose regulation?
It produces insulin and glucagon to lower or raise blood glucose
21What type of gland is the pancreas?
Both an endocrine and an exocrine gland
22What is the role of alpha cells in the pancreas?
They produce glucagon to increase blood glucose
23What is the role of beta cells in the pancreas?
They produce insulin to decrease blood glucose
24What is somatostatin and where is it produced?
A hormone produced by delta cells in the pancreas that inhibits insulin and glucagon release
25How does insulin affect fat metabolism?
It inhibits lipolysis and promotes triglyceride synthesis in adipose tissue
26How does insulin affect muscle tissue?
It stimulates glycogen synthesis and protein synthesis by promoting amino acid uptake
27What happens to insulin before it becomes active?
It is stored as proinsulin, an inactive form, in the pancreatic islets
28What are mineralocorticoids, and where are they produced?
Hormones produced in the adrenal cortex that regulate salt and water balance
29What is aldosterone's primary function?
To increase sodium reabsorption, which helps regulate blood pressure and fluid balance
30How does the hypothalamus communicate with the anterior pituitary?
Through the release of regulatory hormones that control anterior pituitary secretions
31What is the main function of adrenaline?
To enhance the fight-or-flight response by increasing heart rate and blood pressure
32How do glucocorticoids affect blood glucose levels?
They increase blood glucose by promoting fat and protein breakdown
33What is the role of the hypothalamus in the endocrine system?
It regulates hormone release from the pituitary gland and other endocrine functions
34How does the thyroid affect metabolism?
It regulates the metabolic rate and heat production, impacting carbohydrate, protein, and fat metabolism
35What does negative feedback mean in the endocrine system?
A process where the output of a system counteracts or reduces the initial stimulus
36What hormone is involved in bone growth and where is it produced?
Growth hormone (GH), produced by the anterior pituitary