Blood, Cardiovascular, and Lymphatic/Immune Systems – Exam Review

A comprehensive set of question–and–answer flashcards covering blood physiology, cardiovascular anatomy and function, and lymphatic/immune concepts for exam preparation.

What are the three primary functions of blood?

Transport (O₂, nutrients, wastes, hormones), regulation (pH, temperature, fluid balance), and protection (clotting, immunity).

Name the two main components of blood.

Plasma (liquid matrix) and formed elements (RBCs, WBCs, platelets).

What is the buffy coat in centrifuged blood?

A thin whitish layer between plasma and RBCs that contains WBCs and platelets.

Define hematocrit.

The percentage of whole-blood volume composed of red blood cells (~45%).

Which formed elements lack nuclei?

Erythrocytes (RBCs) and platelets.

What is the normal pH range of blood?

7.35 – 7.45.

State the main function of the plasma protein albumin.

Maintains osmotic pressure and transports certain molecules.

What is the primary function of erythrocytes?

Transport oxygen (via hemoglobin) and a small amount of carbon dioxide.

Define hemoglobin.

The oxygen-binding protein inside red blood cells.

What happens to red blood cells in sickle-cell anemia?

Abnormal hemoglobin causes RBCs to assume a sickle shape, leading to vessel blockage.

Differentiate diapedesis and chemotaxis.

Diapedesis: WBCs squeeze through capillary walls; chemotaxis: WBCs follow chemical signals to sites of infection.

What is leukemia?

Cancer of white blood cells characterized by excessive, abnormal WBC production.

List the two major groups of white blood cells.

Granulocytes (neutrophils, eosinophils, basophils) and agranulocytes (lymphocytes, monocytes).

Explain the function and origin of platelets.

Cell fragments from megakaryocytes; essential for blood clotting.

Where does hematopoiesis occur in adults?

Red bone marrow.

Name the hormone that stimulates red blood cell production.

Erythropoietin (EPO) released mainly by the kidneys.

Which two hormone families regulate WBC production?

Colony-stimulating factors (CSFs) and interleukins.

Define hemostasis.

The process that stops bleeding: vascular spasm, platelet plug formation, and coagulation.

Differentiate a thrombus from an embolus.

Thrombus: stationary clot in a vessel; embolus: clot fragment traveling in the bloodstream.

What are thrombocytopenia and hemophilia?

Thrombocytopenia: low platelet count; hemophilia: inherited deficiency of clotting factors—both cause bleeding tendency.

List the basic ABO blood types with their antigens and antibodies.

Type A: A antigen, anti-B antibodies; Type B: B antigen, anti-A; Type AB: A and B antigens, no antibodies (universal recipient); Type O: no antigens, anti-A and anti-B antibodies (universal donor).

What is agglutination in blood typing?

Clumping of red cells when incompatible blood types mix.

Explain the Rh factor.

Rh⁺ blood has the Rh antigen; Rh⁻ lacks it but can produce anti-Rh antibodies upon exposure.

Name the three tissue layers of the heart wall from outer to inner.

Epicardium, myocardium, endocardium.

Identify the four chambers of the heart and their basic roles.

Right & left atria (receive blood); right & left ventricles (pump blood out).

What are the two septa in the heart?

Interatrial septum and interventricular septum.

Define coronary circulation.

The system of vessels that supplies blood to the heart muscle itself.

Compare pulmonary and systemic circulation routes.

Pulmonary: heart → lungs → heart; systemic: heart → body tissues → heart.

Name the atrioventricular and semilunar valves.

AV valves: tricuspid (right), bicuspid/mitral (left); semilunar valves: pulmonary and aortic.

What is the role of the SA node?

Acts as the heart’s pacemaker, initiating each heartbeat.

What is the function of the AV node?

Delays the impulse, then transmits it to the ventricles.

Describe the AV bundle and Purkinje fibers.

Conducting pathways that rapidly distribute the impulse through the ventricles, ensuring coordinated contraction.

Differentiate myocardial ischemia from infarction.

Ischemia: reduced blood flow to heart muscle; infarction: death of cardiac tissue (heart attack).

Outline the basic phases of the cardiac cycle.

Systole (contraction) and diastole (relaxation); “lub-dup” sounds correspond to valve closures.

List four categories of factors that influence heart rate.

Autonomic nervous system, hormones, ion concentrations, and physical factors (e.g., temperature, exercise).

Compare the structure and function of arteries, veins, and capillaries.

Arteries: thick walls, high pressure; veins: thinner, valves, low pressure; capillaries: one-cell-thick for exchange.

What is the ‘muscular pump’ in venous return?

Skeletal muscle contractions that squeeze veins and propel blood toward the heart.

Explain hepatic portal circulation.

Blood from digestive organs passes through the liver for detoxification before returning to the heart.

Define blood pressure and state how it is expressed.

Force exerted by blood on arterial walls, recorded as systolic/diastolic (e.g., 120/80 mm Hg).

What numerical values define hypertension?

Persistent blood pressure ≥ 140/90 mm Hg.

Name the two main structural components of the lymphatic system.

Lymphatic vessels and lymphoid organs/tissues.

What is edema?

Abnormal accumulation of interstitial fluid due to impaired lymphatic drainage or other causes.

Define lymph.

Clear fluid formed from leaked plasma that enters lymphatic vessels.

Trace the general path of lymph flow.

Lymphatic capillaries → vessels → trunks → ducts → subclavian veins.

Which body regions are drained by the right lymphatic duct?

Right upper limb, right side of head and neck, and right thorax.

What regions are drained by the thoracic (left) duct?

All body regions below the diaphragm and the left side above the diaphragm.

List three mechanisms that aid the return of lymph to the bloodstream.

One-way valves, skeletal muscle pump, and respiratory pump.

Describe the structure and function of a lymph node.

Bean-shaped filter with an outer cortex (B cells) and inner medulla (macrophages) that cleans lymph and activates immunity.

Give five major lymphoid organs.

Spleen, thymus, tonsils, Peyer’s patches, and appendix.

What are MALT structures?

Mucosa-associated lymphoid tissues found in mucous membrane linings that guard entryways.

Compare innate (nonspecific) and adaptive (specific) immunity.

Innate: fast, broad defenses present at birth; adaptive: slower, antigen-specific, develops memory.

List the four cardinal signs of inflammation.

Redness, heat, swelling, and pain.

How do pyrogens produce a fever?

They reset the hypothalamic ‘thermostat’ to a higher temperature.

Define phagocytosis.

Process in which cells (e.g., neutrophils, macrophages) engulf and digest pathogens or debris.

What is the role of interferons?

Proteins released by virus-infected cells that help protect neighboring cells from viral infection.

Differentiate humoral and cellular adaptive immunity.

Humoral: B cells produce antibodies; cellular: T cells directly attack infected or abnormal cells.

What are antigen-presenting cells (APCs)?

Cells such as dendritic cells, macrophages, and B cells that display antigen fragments to T cells.

Identify the four basic types of acquired immunity.

Naturally acquired active, naturally acquired passive, artificially acquired active (vaccination), and artificially acquired passive (antibody injection).