A&P II Exam Study Set: Chapters 14, 16 & 17

Comprehensive vocabulary flashcards covering key concepts, mechanisms, and formulas from Chapters 14 (Autonomic Nervous System), 16 (Endocrine System), and 17 (The Heart).

Sympathetic Division

The thoracolumbar division of the autonomic nervous system responsible for the fight or flight response during stress.

Parasympathetic Division

The craniosacral division of the autonomic nervous system responsible for rest and digest functions to maintain homeostasis during rest.

Acetylcholine (ACh)

The neurotransmitter that binds to cholinergic receptors, which include nicotinic and muscarinic subtypes.

Adrenergic Receptors

Receptors that bind norepinephrine (NE) and epinephrine (E), categorized into subtypes ̑\alpha_1, ̑\alpha_2, ̑\beta_1, ̑\beta_2, and ̑\beta_3.

Adrenal Medulla

An endocrine structure stimulated by preganglionic sympathetic neurons to release epinephrine and norepinephrine into the bloodstream, prolonging the sympathetic response.

Dual Innervation

The arrangement in which most organs receive nerve fibers from both sympathetic and parasympathetic divisions to cooperatively regulate organ function and maintain homeostasis.

Hormone

A chemical secreted by an endocrine gland into the bloodstream that acts on target cells possessing specific receptors.

Hydrophilic vs. Hydrophobic Hormones

Comparison showing that hydrophilic hormones (amino acid-based and peptides) cannot cross the cell membrane, bind membrane receptors, and can use second messengers; whereas hydrophobic hormones (steroids and thyroid hormone) cross the membrane and bind cytosol/nucleus receptors.

cAMP (Cyclic Adenosine Monophosphate)

An intracellular second messenger activated downstream of a hydrophilic hormone binding to its cell membrane receptor.

Stimuli for Hormone Secretion

The three mechanisms triggering hormone release: hormonal stimulus, humoral stimulus (such as changes in $Ca^{2+}$ or glucose), and neural stimulus.

Anterior Pituitary

The portion of the pituitary gland that produces and secretes its own hormones.

Posterior Pituitary

The portion of the pituitary gland that does not produce hormones, but stores and releases ADH and oxytocin produced by the hypothalamus.

Antidiuretic Hormone (ADH / Vasopressin)

A hormone produced by the hypothalamus and stored in the posterior pituitary that acts on the kidneys to increase water retention and decrease urine production.

Diabetes Insipidus

A condition caused by an abnormal lack of ADH, leading to excessive urination, dehydration, and extreme thirst.

Oxytocin

A hormone produced by the hypothalamus and stored in the posterior pituitary that affects milk secretion, uterine contractions during childbirth, and brain processes related to relationships.

T3 and T4

Major thyroid hormones requiring iodine for synthesis that regulate metabolic rate, thermoregulation, growth, development, and synergize with the sympathetic nervous system.

Hyperthyroidism

A condition resulting from excessive T3/T4 levels, characterized by weight loss, heat intolerance, increased blood pressure, and increased heart rate.

Parathyroid Hormone (PTH)

A hormone released in response to hypocalcemia that increases blood $Ca^{2+}$ by increasing release from bone, kidney reabsorption, and indirect dietary absorption via calcitriol.

Aldosterone

The primary mineralocorticoid produced by the adrenal cortex that regulates $Na^+$ and $K^+$ homeostasis and indirectly promotes water reabsorption.

Cortisol

A glucocorticoid produced by the adrenal cortex that promotes gluconeogenesis and exerts anti-inflammatory effects.

Pancreatic Islet Cells

Endocrine cells of the pancreas comprising Beta (\beta) cells that produce insulin, Alpha (\alpha) cells that produce glucagon, and Delta (\delta) cells that produce somatostatin.

Insulin

A hormone produced by pancreatic beta cells when blood glucose is high to promote glucose storage.

Glucagon

An antagonistic hormone produced by pancreatic alpha cells when blood glucose is low to increase glucose production and release.

Cardiac Conduction Pathway

The electrical pathway of the heart: SA node \rightarrow AV node \rightarrow AV bundle \rightarrow right & left bundle branches \rightarrow Purkinje fibers \rightarrow ventricular contractile cells.

Pacemaker Action Potential Depolarization

The rapid depolarization phase at threshold ($-40\,mV$) in pacemaker cells caused by the opening of voltage-gated $Ca^{2+}$ channels.

Plateau Phase

Phase during a contractile cell action potential where voltage-gated $K^+$ channels remain open while voltage-gated $Ca^{2+}$ channels open, preventing tetany and allowing ventricular filling.

P Wave

An ECG wave representing atrial depolarization.

QRS Complex

An ECG complex representing ventricular depolarization while hiding atrial repolarization.

T Wave

An ECG wave representing ventricular repolarization.

Isovolumetric Contraction

The cardiac cycle phase where ventricles contract with all valves closed prior to ventricular ejection.

Isovolumetric Relaxation

The cardiac cycle phase where ventricles relax with all valves closed prior to ventricular filling.

S1 and S2 Heart Sounds

S1 is caused by the closing of the AV valves; S2 is caused by the closing of the semilunar valves.

Cardiac Output (CO)

The total volume of blood pumped per minute, calculated using the formula $CO = HR \times SV$.

Stroke Volume (SV)

The volume of blood pumped by one ventricle during one contraction, calculated as $SV = EDV - ESV$.

End-Diastolic Volume (EDV)

The volume of blood in a ventricle at the end of ventricular filling.

End-Systolic Volume (ESV)

The volume of blood remaining in a ventricle at the end of ventricular ejection.