Human Anatomy and Physiology: The Endocrine System

These flashcards cover key concepts and functions of the endocrine system as discussed in the Human Anatomy and Physiology lecture notes.

What is the general function of the endocrine system?

SLOW communication and control through hormones.

What do hormones influence in cells?

Metabolic activities of cells.

What is the study of hormones and endocrine organs called?

Endocrinology.

What are the major endocrine glands mentioned?

Pituitary, thyroid, parathyroid, adrenal, and pineal glands.

What is the function of the hypothalamus within the endocrine system?

It is a neuroendocrine organ and the master controller of the endocrine system.

What are the three types of stimuli that endocrine glands respond to?

Neural, hormonal, and humoral.

How do hormones differ from local chemical messengers?

Hormones are released into the bloodstream, while local chemical messengers are not.

What is the difference between water soluble and lipid soluble hormones in terms of transport?

Water soluble hormones dissolve in plasma; lipid soluble hormones must bind to plasma proteins for transport.

Where are receptors for water soluble hormones located?

In the plasma membranes of target cells.

What is the mechanism called when lipid-soluble hormones activate gene expression?

Direct gene activation.

What is the role of cyclic AMP in water soluble hormone action?

It acts as a second messenger that triggers a series of reactions in target cells.

What happens during the change in target cell activation?

Examples include altered membrane permeability, synthesis of enzymes, or stimulated mitosis.

How does the level of hormones affect the quantity of their receptors?

Low hormone levels can lead to up-regulation (more receptors), while high hormone levels can lead to down-regulation (fewer receptors).

What hormones are produced by the posterior pituitary?

Oxytocin and Antidiuretic hormone (ADH).

What does oxytocin stimulate in females?

Uterine contractions during labor and milk ejection.

How does antidiuretic hormone (ADH) affect blood pressure?

It increases blood pressure by promoting water reabsorption in the kidneys.

What hormones are released from the anterior pituitary?

Thyroid-stimulating hormone (TSH), Adrenocorticotropic hormone (ACTH), Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Prolactin (PRL), and Growth Hormone (GH).

What does thyroid-stimulating hormone (TSH) do?

It stimulates the thyroid gland to secrete triiodothyronine (T3) and thyroxine (T4).

What effects does cortisol have on the body?

Increases blood levels of glucose, fatty acids, and amino acids; helps the body handle long-term stress.

What are the effects of parathyroid hormone (PTH)?

Regulates calcium ion levels and is secreted in response to low calcium levels.

What hormones do the adrenal glands produce?

Corticosteroids, catecholamines like epinephrine and norepinephrine.

What is the primary function of the pineal gland?

Secretes melatonin, which regulates sleep-wake cycles.

What hormones does the pancreas produce?

Glucagon (from alpha cells) and insulin (from beta cells).