Related Concept Videos

Veins as Blood Reservoirs01:10

Veins as Blood Reservoirs

Veins, while chiefly responsible for circulating blood back to the heart, also function as storage vessels for blood. They house approximately 64 percent of the body's total blood volume, a feat made possible by their high capacitance—the inherent ability to expand and accommodate large volumes of blood, even under low pressure. The large diameter and thin walls of veins augment their distensibility, significantly more so than arteries, due to their classification as capacitance vessels. When...
Arteries and Arterioles01:16

Arteries and Arterioles

Arteries, the vasculature responsible for transporting blood from the heart, possess robust walls capable of enduring the elevated pressures exerted by the heartbeat. Arteries near the heart are especially thick-walled and enriched with elastic fibers across their three tunics, classifying them as elastic or conducting arteries. These arteries, usually with a diameter exceeding 10 mm, are characterized by their ability to dilate in response to the blood pumped from the heart's ventricles and...
Autoregulation of Blood Flow01:17

Autoregulation of Blood Flow

Autoregulation mechanisms are characterized by their inherent capacity for self-regulation without necessitating specific nervous stimulation or endocrine control. These mechanisms facilitate the adjustment of blood flow and, therefore, perfusion specific to each tissue region. This self-regulation encompasses chemical signals and myogenic controls.
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Anastomoses01:19

Anastomoses

In human anatomy, anastomosis refers to a connection or opening between two things, particularly between blood vessels or other tubular structures. The term is derived from the Greek term 'anastomosis,' which means 'outlet' or 'opening.' This natural network of connections plays a critical role in the survival and functionality of the human body.
Anastomoses can be formed at arterial, venous, and lymphatic vessels.
Arterial Anastomosis: These occur between arteries. They are most common in...
Hemodialysis I: Introduction01:25

Hemodialysis I: Introduction

Hemodialysis (HD) is a medical treatment that artificially removes waste products, excess fluids, and toxins from the blood when the kidneys are no longer able to perform these functions effectively. In this process, blood is filtered through a semipermeable membrane, allowing for the selective removal of waste while preserving necessary components like blood cells and proteins. Hemodialysis is typically performed in patients with end-stage renal disease (ESRD) or severe kidney...
Hormonal Regulation of Blood Pressure01:17

Hormonal Regulation of Blood Pressure

Endocrinal or hormonal intervention in the cardiovascular system is predominantly exerted by the catecholamines - epinephrine and norepinephrine, as well as a slew of hormones that interact with renal function to modulate blood volume.
Epinephrine and Norepinephrine
The adrenal medulla releases epinephrine and norepinephrine, catecholamines that enhance and extend the sympathetic or "fight or flight" physiological response. These hormones escalate heart rate and the force of contraction while...