Endocrine Flashcards
What are hormones?
Hormones are chemical messengers produced by glands in the endocrine system.
Travelling through the bloodstream to regulate various physiological processes, including growth, metabolism, mood, and reproduction.
How do hormones interact with receptors?
Hormones interact with specific receptors on or inside target cells.
Cell surface receptors are found on the membrane and bind to water-soluble hormones, while intracellular receptors are found inside the cell and bind to fat-soluble hormones.
This binding triggers a response that affects the cell’s activity or function.
What is the pathophysiological process that underpins diabetes mellitus?
Diabetes mellitus is a metabolic disorder characterized by high blood glucose levels due to either insufficient insulin production (Type 1 diabetes) or insulin resistance (Type 2 diabetes).
This disrupts glucose metabolism, leading to chronic hyperglycemia and potentially damaging organs and tissues over time.
How are normal blood glucose ranges maintained?
Normal blood glucose levels are regulated by the hormones insulin and glucagon.
After eating, insulin is released from the pancreas to help cells take up glucose, lowering blood sugar.
When blood glucose drops, glucagon is released to signal the liver to release stored glucose, increasing blood sugar to normal levels.
What is the difference between hypoglycemia and hyperglycemia?
Hypoglycemia: Low blood glucose (below 3.9 mmol/L), causing symptoms like shaking, sweating, and confusion.
Hyperglycemia: High blood glucose ( above 7 mmol/L), causing symptoms like thirst, frequent urination, and fatigue.
How do thyroid hormones support homeostasis?
Thyroid hormones (T3 and T4) regulate metabolism by controlling the rate of energy production, heat production, and oxygen consumption in cells.
They support growth, development, and overall body temperature regulation, contributing to homeostasis.
What is the pathophysiology of hyperthyroidism?
Hyperthyroidism is characterized by an overproduction of thyroid hormones, which increases metabolism.
This can lead to symptoms like weight loss, rapid heartbeat, increased body temperature, anxiety, and tremors.
What is the pathophysiology of hypothyroidism?
Hypothyroidism occurs when thyroid hormone is underproduced, leading to a slowed metabolism.
Symptoms include weight gain, fatigue, depression, cold intolerance, and constipation.
What are the effects of the body’s use of stress mechanisms?
The body’s stress mechanisms activate the sympathetic nervous system and release hormones like cortisol and adrenaline, which prepare the body for a “fight or flight” response.
These mechanisms increase heart rate, blood pressure, and glucose availability while suppressing non-essential functions like digestion and immune response.
What is stress in relation to homeostasis in health and disease?
Stress refers to the physiological and psychological responses to a perceived challenge or threat that disrupts homeostasis.
In health, acute stress can be adaptive and temporary, while chronic stress can lead to long-term imbalances, contributing to diseases like cardiovascular conditions, diabetes, and mental health disorders.
What are the key components of the body that are modulated by stress?
Stress modulates various components of the body, including the nervous system, endocrine system, immune system, and cardiovascular system.
Key players include the hypothalamus, pituitary gland, adrenal glands, and sympathetic nervous system.
What are the effects of the resistance phase of stress?
In the resistance phase, the body attempts to adapt to prolonged stress by maintaining elevated levels of stress hormones (e.g., cortisol) to support energy production, suppress non-essential functions, and help the body cope with the stressor over an extended period.
Chronic activation of this phase can lead to immune suppression and other health problems.
What are the effects of the alarm phase of stress?
In the alarm phase, the body reacts to the stressor with the activation of the fight-or-flight response.
This leads to releasing adrenaline and cortisol, increased heart rate, elevated blood pressure, and heightened alertness to prepare for immediate action.
What are potential situations or conditions that present a major challenge to homeostatic systems within the body?
Situations that challenge homeostasis include chronic stress, trauma, severe infections, extreme environmental conditions (e.g., extreme heat or cold), nutrient deficiencies, severe blood loss, and chronic diseases like diabetes, hypertension, and cardiovascular disorders.
These all disrupt the body’s ability to maintain stable internal conditions.
What are the metabolic issues in the GI tract related to malabsorption?
Malabsorption refers to the impaired absorption of nutrients in the GI tract.
Coeliac disease is an example, where ingestion of gluten leads to immune-mediated damage to the small intestine, resulting in poor absorption of nutrients like fat, protein, and carbohydrates.
What metabolic issues occur in the liver due to alcoholism?
Alcoholism leads to liver damage through the accumulation of toxins and fat in liver cells, inflammation, and scarring.
This disrupts liver metabolism, impairing functions like detoxification, bile production, and nutrient storage.
It can lead to conditions like fatty liver, cirrhosis, and hepatic encephalopathy.
What is jaundice and how does it relate to the GI tract?
Jaundice is the yellowing of the skin and eyes due to high levels of bilirubin, a byproduct of red blood cell breakdown.
It occurs when the liver is unable to process or excrete bilirubin properly, which can be caused by liver disease, bile duct obstruction, or hemolytic anemia.
What is the pathophysiology of peptic ulcers caused by Helicobacter pylori?
Helicobacter pylori infection causes inflammation in the stomach lining, leading to the formation of peptic ulcers.
The bacteria weaken the protective mucous layer in the stomach, allowing stomach acid to damage the underlying tissue, resulting in pain, bleeding, and potential perforation.
What is inflammatory bowel disease (IBD)?
Inflammatory bowel disease includes conditions like Crohn’s disease and ulcerative colitis, where chronic inflammation of the digestive tract occurs.
This can lead to symptoms like diarrhoea, abdominal pain, and malnutrition, with potential complications like fistulas, strictures, and an increased risk of colon cancer.
What are motility problems in the GI system, and how do they affect physiology?
Motility problems like diarrhoea occur when the movement of food through the digestive tract is either too fast (leading to inadequate absorption) or too slow (leading to constipation).
Diarrhoea, in particular, is characterized by frequent, watery stools and can result in dehydration, electrolyte imbalance, and malnutrition
What is the physiological process of vomiting?
Vomiting is a complex process controlled by the vomiting centre in the brain. It involves the contraction of abdominal muscles and the relaxation of the lower oesophagal sphincter, causing the stomach’s contents to be expelled through the mouth.
Vomiting can be triggered by irritation of the GI tract, infections, toxins, motion sickness, or neurological signals.
What is the female reproductive system and how does it function?
The female reproductive system consists of the ovaries, fallopian tubes, uterus, cervix, and vagina.
It functions in egg production, fertilization, and gestation. The menstrual cycle involves hormone regulation, ovulation, and preparation of the uterus for pregnancy.
What is polycystic ovary syndrome (PCOS)?
PCOS is a common hormonal disorder in women that causes enlarged ovaries with multiple small cysts.
It leads to irregular periods, excess androgen (male hormones), and potential infertility due to disrupted ovulation.
What is the male reproductive system and how does it function?
The male reproductive system includes the testes, epididymis, vas deferens, prostate, seminal vesicles, and penis.
Its primary function is sperm production and delivery for fertilization.
Testosterone plays a key role in spermatogenesis and male characteristics.
What is cryptorchidism?
Cryptorchidism is a condition in which one or both testes fail to descend into the scrotum before birth.
It can cause infertility or increase the risk of testicular cancer if not corrected.
What are common prostate issues in men?
Common prostate issues include benign prostatic hyperplasia (BPH), where the prostate enlarges and causes urinary problems, and prostate cancer, which can lead to pain, difficulty urinating, and potential spread to other organs.
What factors and behaviours can affect ovulation and sexual performance in both males and females?
Factors affecting ovulation and sexual performance include stress, diet, exercise, hormonal imbalances, infections, and conditions like pelvic prolapse in females.
In males, factors such as testicular health and stress can affect sexual function and fertility.
What are gonadotropins, and what role do they play in reproduction?
Gonadotropins include follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which regulate the function of the ovaries in females and testes in males.
FSH stimulates follicle growth in females and sperm production in males, while LH triggers ovulation in females and testosterone production in males.
How does testosterone affect male reproduction?
Testosterone is the primary male sex hormone responsible for the development of male reproductive tissues, sperm production, and the maintenance of male characteristics like muscle mass, facial hair, and deep voice.
