Chapter 17: Blood Lecture Notes

Vocabulary-style flashcards covering the components, functions, characteristics, and disorders of blood as described in the Chapter 17 lecture notes.

Arteries

Conducting hoses that carry blood away from the heart.

Veins

Conducting hoses that carry blood to the heart.

Capillaries

Connections between arteries and veins that serve as the site of exchange with tissues.

Whole blood

A fluid connective tissue consisting of plasma and formed elements.

Blood Temperature

Approximately $38^\circ\text{C}$ ($100.4^\circ\text{F}$), which is slightly above normal body temperature.

Blood pH

Slightly alkaline, ranging between $7.35$ and $7.45$.

Fractionation

The process of separating whole blood into plasma and formed elements.

Plasma

The fluid matrix of blood, making up about $55\%$ of blood volume and consisting of more than $90\%$ water.

Albumins

The most abundant plasma proteins ($60\%$) that transport fatty acids and steroid hormones and are major contributors to plasma osmolarity.

Globulins

Plasma proteins ($35\%$) that include antibodies (immunoglobulins) and transport globulins.

Fibrinogen

A soluble plasma protein ($4\%$) that functions in clotting and is converted into insoluble fibrin.

Serum

The fluid left in a blood sample after the conversion of fibrinogen to fibrin.

Hemopoiesis

Also known as hematopoiesis, it is the process of producing formed elements.

Erythrocytes

Red blood cells (RBCs) that make up $99\%$ of formed elements and are essential for oxygen transport.

Hematocrit

Also called packed cell volume (PCV), it is the percentage of formed elements in blood; averages $46\%$ for males and $42\%$ for females.

Rouleaux

Stacks formed by red blood cells that allow smooth blood flow through narrow vessels.

Hemoglobin (Hb)

A protein in RBCs with a complex quaternary structure (4 subunits) that transports respiratory gases.

Oxyhemoglobin

The substance formed when iron ($Fe$) ions in hemoglobin interact with oxygen.

Anemia

A condition that results when the hematocrit or Hb content of RBCs is reduced, interfering with oxygen delivery.

Erythropoiesis

The specific process of red blood cell formation which occurs in red bone marrow.

Erythropoietin (EPO)

A hormone secreted by the kidneys and liver in response to low oxygen levels (hypoxia) to stimulate RBC production.

Biliverdin

A green organic compound formed during the recycling of hemoglobin when iron is removed from the heme unit.

Bilirubin

An orange pigment converted from biliverdin that is excreted by the liver in bile.

Jaundice

A condition caused by the buildup of bilirubin in the body.

Surface Antigens

Substances on plasma membranes, such as A, B, and Rh, that identify cells to the immune system.

Agglutinins

Antibodies in plasma that attack foreign RBC antigens, causing clumping.

Agglutination

The clumping of foreign cells that occurs when surface antigens are exposed to corresponding antibodies.

RhoGAM

A shot administered to Rh- mothers to prevent the development of anti-Rh antibodies that could attack an Rh+ fetus.

Leukocytes

White blood cells (WBCs) which contain nuclei and organelles and function in body defense.

Chemotaxis

The process by which WBCs are attracted to specific chemical stimuli.

Diapedesis

The migration of WBCs from capillaries into the surrounding tissues.

Neutrophils

Granulocytes making up $50-70\%$ of circulating WBCs; the first to arrive at an injury site to phagocytize bacteria.

Eosinophils

Granulocytes ($2-4\%$) that attack large parasites and are active during allergic responses.

Basophils

Granulocytes ($<1\%$) that release histamine to dilate blood vessels and heparin to prevent clotting.

Monocytes

Large spherical WBCs that enter peripheral tissues to become aggressive phagocytes called macrophages.

Lymphocytes

WBCs ($20-40\%$) involved in the adaptive immune response, including T cells and B cells.

Leukopenia

A disorder characterized by an abnormally low white blood cell count.

Leukocytosis

A disorder characterized by an abnormally high white blood cell count.

Platelets

Also called thrombocytes, these are cell fragments involved in the clotting system that circulate for $9-12$ days.

Hemostasis

The process of stopping blood loss, consisting of the vascular, platelet, and coagulation phases.

Thrombin

An enzyme that mediates the conversion of soluble fibrinogen into insoluble fibrin during the coagulation phase.

Fibrinolysis

The process where a blood clot gradually dissolves.

Thrombocytopenia

A condition indicated by an abnormally low platelet count.

Sickle cell anemia

A recessive inherited disorder where fragile RBCs take on a shape that can get stuck in capillaries.

Bacteremia

A condition where bacteria circulate in the blood but do not replicate there.

Sepsis

A blood infection where bacteria are actively multiplying and producing toxins in the blood.

Malaria

A blood infection caused by the parasite Plasmodium and transmitted by mosquitoes.