5Capillary Exchange, Blood Pressure, and Endocrine System Vocabulary

A set of vocabulary flashcards covering capillary exchange mechanisms, blood pressure calculations, and key hormones of the endocrine system based on lecture notes.

Hydrostatic pressure

The pressure that pushes fluid OUT of capillaries, which reaches its highest level at the arterial end.

Osmotic/oncotic pressure

The pressure that pulls fluid INTO capillaries.

Net filtration pressure (NFP)

The net fluid movement pressure across capillaries, where a positive NFP results in filtration (fluid moving OUT) and a negative NFP results in reabsorption (fluid moving IN).

Transcytosis

A cellular process used to transport large substances through endothelial cells via a pathway where a large molecule is taken into a vesicle, moved across the cell, and released.

Systolic pressure (SBP)

The blood pressure exerted during ventricular contraction.

Diastolic pressure (DBP)

The blood pressure exerted during ventricular relaxation.

Pulse pressure

The difference between systolic blood pressure and diastolic blood pressure, calculated as $\text{Pulse pressure} = \text{SBP} - \text{DBP}$ (for example, $120 - 80 = 40$\text{ mmHg}).

Mean Arterial Pressure (MAP)

The average arterial pressure calculated using SBP and DBP with the formula $\text{MAP} \rightleftharpoons \text{DBP} + \frac{1}{3}(\text{SBP} - \text{DBP})$ (for example, for a blood pressure of $120/80$\text{ mmHg}, $\text{MAP} \rightleftharpoons 80 + \frac{1}{3}(40) \rightleftharpoons 93$\text{ mmHg}).

Endocrine system

A system that releases hormones into the bloodstream to travel to target cells with correct receptors, producing generally slower and longer-lasting effects compared to the fast, short-lived signals of the nervous system.

Steroid hormones

Lipid-soluble hormones—including cortisol, aldosterone, estrogen, progesterone, and testosterone—that cross the cell membrane, bind intracellular receptors, and affect gene transcription to cause new protein synthesis.

Thyroid hormones ($\text{T3}$ and $\text{T4}$)

Hormones stimulated by anterior pituitary TSH that increase basal metabolic rate (BMR), metabolism, oxygen consumption, and heat production.

Parathyroid hormone (PTH)

A hormone that raises blood $\text{Ca}^{2+}$ levels by increasing bone resorption and kidney calcium retention, rather than promoting osteoblast-driven bone formation.

Aldosterone

A hormone that regulates $\text{Na}^+$ and $\text{K}^+$ by increasing sodium reabsorption and potassium secretion in the kidneys; saving $\text{Na}^+$ draws water with it, contributing to increased blood volume.

Cortisol

A hormone produced by the adrenal cortex that regulates the stress response, increases blood glucose availability, provides anti-inflammatory effects, and suppresses immune activity.

Hypercortisolism

A state of excess cortisol production leading to Cushing syndrome.

Cushing disease

A specific etiology of hypercortisolism where excess pituitary ACTH causes excess cortisol production.