Endocrine System Flashcards
Hormones
What are Primary Endocrine Organs?
Organs whose main function is to produce hormones (e.g., pituitary, thyroid)
Primary endocrine organs are critical for hormone production and regulation in the body.
What are Secondary Endocrine Organs?
Part of another system but also produce hormones (e.g., pancreas, gonads)
Secondary endocrine organs have functions beyond hormone production.
What are hormones?
Chemical messengers released into the blood
Hormones play a vital role in regulating various physiological processes.
How do hormones interact with target cells?
Bind to specific target cells with matching receptors
This interaction is crucial for hormone function.
What are the three types of chemical signals?
- Endocrine: Travels in blood to distant targets
- Paracrine: Targets nearby cells
- Autocrine: Targets the same cell that produced it
Each type of signal has a unique mechanism of action.
What are Amino Acid-Based Hormones?
Hydrophilic, bind to membrane receptors
Examples include insulin and epinephrine.
What are Steroid Hormones?
Hydrophobic, derived from cholesterol, bind to intracellular receptors
Examples include cortisol and estrogen.
What is Negative Feedback in hormone regulation?
Maintains homeostasis (e.g., blood sugar regulation)
Negative feedback is essential for stabilizing physiological systems.
What is Positive Feedback in hormone regulation?
Enhances a response (e.g., oxytocin during childbirth)
Positive feedback loops are less common and often drive processes to completion.
What hormones are produced by the Anterior Pituitary?
- TSH
- ACTH
- GH
- FSH
- LH
- Prolactin
The anterior pituitary plays a significant role in regulating other endocrine glands.
What hormones are released by the Posterior Pituitary?
- Oxytocin
- ADH
These hormones are produced in the hypothalamus and stored in the posterior pituitary.
What hormones does the Thyroid Gland produce?
- T3
- T4
- Calcitonin
T3 and T4 regulate metabolism, while calcitonin lowers blood calcium levels.
What hormone does the Parathyroid Gland secrete?
PTH (Parathyroid Hormone)
PTH raises blood calcium levels.
What hormones are produced by the Adrenal Cortex?
- Cortisol
- Aldosterone
- Androgens
These hormones are involved in stress response and regulating water balance.
What hormones are released by the Adrenal Medulla?
- Epinephrine
- Norepinephrine
These hormones are crucial for the fight-or-flight response.
What hormones does the Pancreas produce?
- Insulin
- Glucagon
Insulin lowers blood glucose, while glucagon raises it.
What hormones do the Ovaries produce?
- Estrogen
- Progesterone
Estrogen is responsible for secondary sex characteristics; progesterone maintains the uterine lining.
What hormone do the Testes produce?
Testosterone
Testosterone is essential for sperm production and male characteristics.
What is the HPA Axis?
Hypothalamus → CRH → Pituitary → ACTH → Adrenal Cortex → Cortisol
This axis regulates the body’s response to stress.
What is the HPT Axis?
Hypothalamus → TRH → Pituitary → TSH → Thyroid → T3/T4
This axis regulates thyroid hormone levels.
What is Hypothyroid condition?
Goiter
Hypothyroidism is characterized by insufficient thyroid hormone production.
What is Hyperthyroid condition?
Grave’s disease, exophthalmos
Hyperthyroidism results from excessive thyroid hormone production.
What is Type 1 Diabetes?
Insulin absent
Type 1 diabetes is often autoimmune and requires insulin therapy.
What is Type 2 Diabetes?
Insulin resistance
Type 2 diabetes is often related to lifestyle factors and can be managed with diet and exercise.
What is Cushing’s Syndrome?
Excess cortisol, often due to overuse of corticosteroids or tumors
Cushing’s syndrome can lead to various health issues, including weight gain and high blood pressure.
What is Up-Regulation?
Increase in the number of hormone receptors on a cell
This process may occur in response to low hormone levels.
What is Down-Regulation?
Decrease in receptor numbers due to prolonged exposure to high hormone levels
This can lead to reduced sensitivity to hormones.
What is Cyclic AMP (cAMP)?
A second messenger that amplifies the hormone’s signal
cAMP plays a critical role in signal transduction pathways.
What are Humoral Stimuli?
Hormone release triggered by blood levels of certain ions or nutrients
This mechanism is important for regulating metabolic processes.
What are Neural Stimuli?
Hormone release triggered by nerve signals
This type of stimulus is crucial in the fight-or-flight response.
