BIO 313: Human Anatomy and Physiology II - Blood, Lymphatic, and Cardiovascular Systems

Flashcards covering blood composition, clotting cascades, blood typing, lymphatic structures, adaptive immunity, and cardiovascular physiology based on lecture notes.

Hematology

The study of blood and blood-forming tissues.

Plasma

The fluid portion of blood (accounting for $55\%$ of whole blood volume) containing water, ions, hormones, nutrients, vitamins, and soluble proteins such as albumin and globulins.

Buffy Coat

The thin middle layer of centrifuged blood (accounting for $<1\%$ of whole blood volume) consisting of leukocytes (white blood cells) and platelets.

Erythrocytes

Denucleated red blood cells with a lifespan of approximately $120\,\text{days}$ that contain hemoglobin for transporting $O_2$ to tissues and $CO_2$ away from tissues.

Hematocrit

The percentage of total blood volume composed of red blood cells, normally around $42\text{--}45\%$.

Formed Elements

The cellular and cell-fragment components of blood, which include erythrocytes, leukocytes, and platelets (buffy coat + RBCs).

Albumin

The most abundant plasma protein ($60\%$ of plasma proteins), which serves as a major carrier protein for lipid-soluble substances and contributes significantly to blood osmotic pressure.

Globulins

A category of plasma proteins ($30\%$ of total plasma proteins) that includes immunoglobulins (antibodies) involved in immune defense.

Hemoglobin

A tetrameric protein composed of two ̑pha-globin and two ̢eta-globin subunits, each bound to a non-protein heme group capable of carrying one $O_2$ molecule.

Heme

A non-protein pigment molecule within hemoglobin containing a central iron ($Fe$) atom necessary for binding oxygen.

Erythropoiesis

The process of red blood cell production occurring in the red bone marrow of spongy bone, derived from myeloid stem cells.

Erythropoietin (EPO)

A glycoprotein hormone released primarily by the kidneys when reduced oxygen-carrying capacity is detected, signaling red bone marrow to increase erythrocyte production.

Bilirubin

A yellow pigment produced from the breakdown of heme during RBC recycling, which is transported to the liver, secreted into bile, and excreted in feces.

Jaundice

A condition characterized by yellowing of the skin and sclera due to elevated circulating bilirubin, often resulting from liver dysfunction, gallbladder obstruction, or excessive hemolysis.

Polycythemia

An abnormal elevation in erythrocyte count (hematocrit $>48\%$), leading to increased blood viscosity ('sludgy blood') and elevated blood volume.

Anemia

A deficiency of healthy red blood cells or hemoglobin resulting in reduced oxygen-carrying capacity of the blood.

Iron-Deficiency Anemia

A microcytic ('small cell') anemia resulting from insufficient iron required for heme synthesis, often caused by hemorrhage, menstruation, or dietary insufficiency.

Sickle Cell Anemia

A genetic disease caused by a point mutation in the ̢eta-hemoglobin gene, causing red blood cells to deform into a sickle shape under low $O_2$ conditions and agglutinate.

Pernicious Anemia

A macrocytic ('big cell') anemia caused by Vitamin $B_{12}$ deficiency, often due to a lack of intrinsic factor required for B12 absorption in the gastrointestinal tract.

Hemostasis

The multi-step physiological process that stops bleeding from a damaged blood vessel, comprising vascular spasm, platelet plug formation, and blood coagulation.

Thrombocytopenia

An abnormally low platelet count that impairs normal blood clotting and leads to excessive bleeding or bruising.

Extrinsic Clotting Mechanism

A rapid blood coagulation pathway initiated by damaged perivascular tissues releasing tissue thromboplastin (Factor III).

Intrinsic Clotting Mechanism

A blood coagulation pathway initiated entirely within the bloodstream when platelets adhere to exposed collagen or plaques and activate Factor XII.

Prothrombin Activator

An enzymatic complex formed by active Factor X ($Xa$), Factor V, $Ca^{2+}$, and platelet factor 3 ($PF_3$) that converts inactive prothrombin (Factor II) into active thrombin.

Fibrinolysis

The enzymatic breakdown of a fibrin clot during wound healing, mediated primarily by plasmin.

Plasmin

An active proteolytic enzyme converted from plasminogen that dissolves fibrin polymers into fibrin degradation products.

Kallikrein

An enzyme activated by Factor XII that converts inactive plasminogen into active plasmin during clot dissolution.

Hemophilia A

An X-linked recessive bleeding disorder caused by a mutation or deficiency in clotting Factor VIII.

Hemophilia B

An X-linked recessive bleeding disorder caused by a mutation or deficiency in clotting Factor IX.

Thrombosis

The abnormal condition of blood clot formation (thrombus) inside an intact blood vessel.

Embolus

A blood clot fragment or foreign mass that breaks loose from its site of origin and travels through the circulation until becoming lodged in a smaller vessel.

Heparin

An anticoagulant released naturally by basophils and mast cells that inhibits thrombin to prevent blood clotting.

Warfarin (Coumadin)

An oral anticoagulant medication that acts by inhibiting the synthesis of Vitamin K-dependent clotting factors in the liver.

Tissue Plasminogen Activator (tPA)

A thrombolytic ('clot-buster') drug that directly activates plasminogen to convert into plasmin for rapid dissolution of blood clots.

Leukocytosis

An abnormally high total white blood cell count (WBC > 10{,}000\,\text{cells/̢L}), frequently caused by infection or leukemia.

Leukopenia

An abnormally low white blood cell count, which can result from HIV infection, chemotherapy, or autoimmune diseases.

Myeloid Leukemia

A type of blood cancer characterized by uncontrolled proliferation of immature cells of the myeloid lineage (granulocytes or monocytes).

Lymphoid Leukemia

A type of blood cancer characterized by uncontrolled proliferation of immature cells of the lymphoid lineage (lymphocytes).

Lymphedema

Tissue swelling caused by the accumulation of interstitial fluid due to impaired lymphatic drainage.

Lacteals

Specialized lymphatic capillaries located in the villi of the small intestine that absorb dietary lipids.

Right Lymphatic Duct

The lymphatic duct that drains lymph from the upper right torso, right arm, and right side of the head and neck, emptying into the right subclavian vein.

Thoracic Duct

The main lymphatic collecting duct that drains lymph from the left side of the upper body and all body regions below the diaphragm, emptying into the left subclavian vein.

Cisterna Chyli

A dilated sac at the inferior end of the thoracic duct that receives lipid-rich lymph (chyle) from the intestinal trunk.

Red Pulp

Splenic tissue composed of venous sinuses filled with erythrocytes, reserve monocytes, and platelets, serving to filter old or damaged RBCs.

White Pulp

Splenic tissue consisting of lymphocytes and macrophages clustered around central arterioles, involved in immune surveillance.

Agglutination

The clumping together of red blood cells caused by antibodies binding to specific surface antigens.

Universal Donor

A individual with Type O-negative blood, whose erythrocytes lack A, B, and Rh antigens and can be transfused to any ABO/Rh recipient.

Universal Recipient

An individual with Type AB-positive blood, whose plasma lacks anti-A, anti-B, and anti-Rh antibodies and can safely receive red blood cells of any ABO/Rh type.

Erythroblastosis Fetalis

A severe hemolytic disease of the newborn occurring when maternal anti-Rh (anti-D) antibodies cross the placenta and destroy Rh-positive fetal erythrocytes.

Class I MHC Proteins

Major histocompatibility complex surface proteins present on all nucleated cells that present intracellular viral or tumor antigens to cytotoxic T cells.

Class II MHC Proteins

Major histocompatibility complex surface proteins present on antigen-presenting cells (APCs) that display extracellular antigen fragments to helper T cells.

Endocardium

The thin inner endothelial lining of the heart chambers, continuous with the vascular endothelium of blood vessels.

Myocardium

The thick middle layer of the heart wall composed of contractile cardiac muscle cells (cardiomyocytes).

Epicardium

The visceral layer of the serous pericardium that forms the outermost surface layer of the heart wall.

Cardiac Tamponade

A life-threatening compression of the heart muscle caused by excessive fluid accumulation within the pericardial cavity.

Patent Foramen Ovale

A congenital cardiac anomaly in which the fetal interatrial opening (foramen ovale) fails to close after birth, permitting blood shunting between atria.

Sinoatrial (SA) Node

The primary pacemaker of the heart located in the right atrium, which spontaneously generates action potentials at an intrinsic rate of approximately $100\,\text{bpm}$.

Atrioventricular (AV) Node

A node of specialized conducting tissue that delays action potential propagation between atria and ventricles, allowing complete atrial contraction prior to ventricular systole.

Purkinje Fibers

Large subendocardial conducting fibers that rapidly conduct electrical action potentials throughout the ventricular myocardium.

P Wave

The initial wave on an ECG trace representing atrial depolarization.

QRS Complex

The prominent waveform on an ECG trace representing rapid ventricular depolarization.

T Wave

The deflection on an ECG trace representing ventricular repolarization.

Sodium 'Funny' Current ($I_f$)

A hyperpolarization-activated inward sodium current in pacemaker cells of the SA node that initiates slow pacemaker potential depolarization.

Calcium-Induced Calcium Release (CICR)

The mechanism in cardiac muscle excitation-contraction coupling where extracellular $Ca^{2+}$ entering through L-type calcium channels triggers massive $Ca^{2+}$ release from the sarcoplasmic reticulum.

Chronotropic Effect

An effect that alters heart rate (a positive chronotropic agent increases rate, while a negative chronotropic agent decreases rate).

Inotropic Effect

An effect that alters myocardial contractility or force of contraction (a positive inotropic agent increases force, while a negative inotropic agent decreases force).

Frank-Starling Mechanism

The intrinsic property of the heart where increased end-diastolic volume (ventricular stretch) increases stroke volume during the subsequent contraction.

Stroke Volume (SV)

The volume of blood ejected by a ventricle during a single contraction, calculated as $SV = EDV - ESV$.

Cardiac Output (CO)

The volume of blood pumped by a ventricle per minute, calculated as $CO = HR \times SV$.

Ejection Fraction (EF)

The fraction of end-diastolic blood volume ejected from the ventricle during systole, calculated as $EF = \frac{SV}{EDV}$.

S1 Heart Sound

The first heart sound ('lub') caused by turbulence and vibration associated with the closure of the atrioventricular (tricuspid and bicuspid) valves at the beginning of ventricular systole.

S2 Heart Sound

The second heart sound ('dupp') caused by turbulence associated with the closure of the semilunar (aortic and pulmonary) valves at the beginning of ventricular diastole.