Mammalian Circulation

A set of flashcards covering key vocabulary and concepts related to mammalian circulation, including components of blood, heart structure, and related medical conditions.

Leukocytes

Cells involved in defense and immunity.

Platelets

Cell fragments that play a role in blood clotting.

Erythrocytes

Red Blood Cells responsible for transporting oxygen (O2) and some carbon dioxide (CO2).

Plasma

The liquid component of blood that makes up 55% of blood volume, composed of water, ions, and electrolytes.

EPO

Erythropoietin, a hormone that stimulates the production of red blood cells by the bone marrow.

Hemoblast

A stem cell that gives rise to red blood cells.

Atria

The upper chambers of the heart that receive blood.

Erythrocyte life cycle

Hemoblast (in red bone marrow), which differentiates into a proerythroblast. Hemoglobin is synthesized, and the nucleus is ejected. The cell becomes a reticulocyte, an immature RBC released into the bloodstream. After 1-2 days, it matures into a functional erythrocyte, circulating for approximately 100-120 days before being removed by macrophages in the spleen, liver, and bone marrow.

Pulmonary circuit

The circuit of blood flow that carries deoxygenated blood to the lungs for oxygenation.

Systemic circuit

The circuit of blood flow that carries oxygenated blood from the heart to the body.

Blood pressure

The force exerted by circulating blood on the walls of blood vessels, influenced by factors like blood volume and vessel constriction.

Atherosclerosis

A condition where there is a buildup of plaque in arterial walls, leading to hardening and narrowing of the arteries.

Angioplasty

A medical procedure to widen narrowed or blocked blood vessels using a balloon catheter.

Stent

A small mesh tube inserted into a blood vessel after angioplasty to keep it open.

Bypass surgery

A surgical procedure that creates a new route for blood to flow to the heart by bypassing a blocked artery.

Plaque removal

Surgery to remove plaque form large blood vessels

Steps/Locations of the Systemic Circuit

 RA → RV → Pulmonary A → Lung capillaries → Pulmonary V → LA → LV → Aorta → Either goes to upper or lower body capillaries → Veins (inferior vena cava or superior vena cava) back to heart.

pulmonary valve

The heart valve between the right ventricle and the pulmonary artery prevents backflow intothe right ventricle.

tricuspid valve

The heart valve between the right atrium and right ventricle that allows blood to flow from the atrium to the ventricle while preventing backflow.

aortic valve

The heart valve between the left ventricle and the aorta that prevents backflow into the ventricle after blood is pumped into the aorta.

mitral valve

The heart valve between the left atrium and left ventricle that allows blood to flow from the atrium to the ventricle while preventing backflow.

How does EPO maintains RBC homeostasis?

When oxygen levels in the blood decrease, cells in the kidneys detect this change. This triggers the release of hypoxia-inducible factors (HIFs). HIFs stimulate the kidneys to produce and release more EPO. EPO then travels to the red bone marrow leading to an increase in RBC production. O2 is needed to break down HIFs and stop EPO production and thus RBC production.

endothelium

All Vessels are lined with endothelium, which is smooth and stretchy and minimizes resistance.

Capillaries

connect arteries and veins and are the site of exchange between blood and tissues.