Blood Anatomy and Physiology Flashcards

Vocabulary practice flashcards covering blood components, formed elements, plasma proteins, hematopoiesis, red blood cell function, blood typing, and white blood cell varieties based on the lecture.

Erythrocyte

The formal scientific term for a red blood cell, characterized by a biconcave disc shape and the absence of a nucleus and organelles, functioning primarily to transport respiratory gases.

Leukocyte

The scientific name for a white blood cell; it is the only formed element that is a complete cell containing a nucleus and organelles, functioning to fight infections and disease.

Thrombocyte

Also known as a platelet; small cellular fragments in the blood visible as tiny purple specks on a blood smear that function in blood clotting.

Blood plasma

The liquid portion of the blood composed mostly of water and dissolved solutes, responsible for transporting formed elements, regulating temperature, and maintaining homeostatic balances.

Buffy coat

The narrow, solid disc layer formed between plasma and red blood cells after blood centrifugation, consisting of white blood cells, platelets, and proteins.

Serum

The pure liquid portion of blood identical to plasma, except that formed elements, platelets, and the clotting protein fibrinogen have been completely removed.

Albumin

The most abundant plasma protein; it contributes to blood viscosity, regulates osmotic pressure, and controls the movement of water into and out of the bloodstream.

Globulins

A class of plasma proteins that include antibodies (such as alpha, beta, and gamma varieties) produced by immune cells to tag and neutralize pathogens.

Fibrinogen

A plasma protein produced by hepatocytes in the liver that is converted into insoluble spider web-like strands of fibrin during the blood clotting cascade.

Hemopoiesis

The process of blood cell formation and differentiation that takes place in the red bone marrow.

Pluripotent stem cell

Also called a hemopoietic stem cell; a stem cell located in the red bone marrow capable of giving rise to all types of formed elements in the blood.

Hemoglobin

A quaternary protein found inside erythrocytes made of four globin protein chains (two alpha and two beta) and four iron-containing heme pigments that bind and carry oxygen molecules.

Heme

A non-protein red pigment disc embedded in each globin chain of hemoglobin with an iron atom at its center that binds an oxygen molecule.

Carbonic anhydrase

An enzyme present within erythrocytes that catalyzes the combination of carbon dioxide and water into carbonic acid, contributing to blood $pH$ buffering.

Hematocrit

The percentage of total blood volume made up of erythrocytes, averaging approximately $45\%$ in human adults.

Erythropoietin (EPO)

A hormone produced and released by the kidneys when oxygen levels drop, signaling red bone marrow to stimulate erythropoiesis via negative feedback.

Polycythemia vera

A primary form of polycythemia caused by cancer of the erythrocyte-producing cells in the bone marrow, which can elevate hematocrit levels up to $80\%$.

Secondary polycythemia

An induced increase in red blood cell concentration resulting from factors such as dehydration, high altitude, emphysema, or blood doping transfusions.

Pernicious anemia

An autoimmune form of anemia where the immune system attacks stomach cells, preventing the absorption of vitamin $B_{12}$ needed for red blood cell development.

Sickle cell anemia

A genetic hemolytic anemia characterized by abnormally sickle-shaped erythrocytes that burst easily and obstruct small capillaries.

Agglutinogen

A surface antigen found on the outside of erythrocytes (such as antigen A, B, or Rh) that determines blood type and can react with specific antibodies.

Agglutinin

A plasma antibody (such as anti-A or anti-B) capable of binding to specific mismatched red blood cell antigens to trigger agglutination.

Agglutination

The clumping together of erythrocytes that occurs when plasma antibodies bind and cross-link foreign surface antigens during an incompatible transfusion.

Transfusion reaction

A systemic immune response occurring when incompatible blood is transfused, leading to erythrocyte agglutination, hemolysis, and potentially kidney failure.

Rh antigen

Also called the D antigen; a surface red blood cell antigen first discovered in the rhesus monkey that classifies blood as either Rh-positive or Rh-negative.

Hemolytic disease of the newborn

Also called erythroblastosis fetalis; a condition where maternal anti-Rh antibodies cross the placenta to attack the erythrocytes of an Rh-positive fetus carried by an Rh-negative mother.

RhoGAM

An injection containing antibodies given to Rh-negative mothers during and after pregnancy to neutralize fetal Rh antigens before maternal anti-D antibody sensitization occurs.

Packed cells

A concentrated preparation of donated red blood cells with most plasma removed, commonly used for transfusing type O blood to minimize the transfer of anti-A and anti-B antibodies.

Neutrophil

The most common granulocyte and primary phagocyte acting as a first responder to engulf and digest bacteria during active infection.

Eosinophil

A granulocyte that attacks parasitic worms (such as tapeworms and flukes) by secreting extracellular enzymes, and participates in allergy, asthma, and autoimmune responses.

Basophil

The least numerous granulocyte, responsible for releasing histamine to cause vasodilation and heparin to inhibit blood clotting during allergic and inflammatory responses.

Histamine

A chemical substance released by basophils that promotes vasodilation of blood vessels and increases fluid leakage into surrounding tissues.

Heparin

An anticoagulant substance produced and released by basophils to prevent inappropriate blood clumping and maintain blood mobility.

Lymphocyte

An agranulocyte responsible for destroying corrupted or cancerous cells, coordinating immune responses, producing antibodies, and providing long-term immunity.

Macrophage

A large, powerful phagocytic tissue cell that develops from a circulating monocyte after it migrates out of the bloodstream to reside in tissues.

Antigen presentation

The immune process by which macrophages display engulfed pathogen fragments to lymphocytes to gain permission to initiate a targeted immune attack.

Leukopenia

An abnormally low white blood cell count caused by factors such as radiation, poisons, or certain infections, leaving an individual immunocompromised.

Leukocytosis

An elevated white blood cell count exceeding $10{,}000$ cells per microliter, typically signaling an active immune response to an infection, allergy, or disease.

Leukemia

A cancer originating in the bone marrow's pluripotent stem cells that results in the excessive production of abnormal, non-functional white blood cells.