anatomy exam 3 study guide

what are the major components of the circulatory system

the heart

blood vessels

blood

what is the circulatory divided into

cardio vascular

lymphatic

what are the major components of the cardiovascular system

heart

Arties

veins

calipers

blood

what is the function of the circulatory system

transports

regulates

protection

what are the different components of blood

plasma

RBC

WBC

palettes

how is plasma formed and its function

formed in liver and it transport, and maintain homeostasis

how is RBC formed and how does it function

formed in red bone marrow and carries O2 and CO2

how is WBC formed and how does it function

formed in red bone marrow and it immune defense

how is platelets form and how does it function

formed in red bone marrow and it blood clots

Hemopoiesis

-The process of blood cell formation.
-Occurs in red bone marrow.
-Produces red blood cells (RBCs), white blood cells (WBCs), and platelets.

Plasma

-The liquid portion of blood
-Made up mostly of water, plus proteins, electrolytes, nutrients, hormones, and waste products.
-Function: Transports substances and maintains blood pressure and volume.

Erythrocyte (Red Blood Cell)

-A red blood cell specialized in transporting oxygen.

- Biconcave, no nucleus, packed with hemoglobin.
-Function: Carry oxygen (O₂) from lungs to tissues and carbon dioxide (CO₂) back to lungs.

Leukocyte (White Blood Cell)

-Immune cells that defend the body against pathogens and foreign substances.

-two types;  Granulocytes, Agranulocytes

 Granulocytes (contain visible granules in cytoplasm)

• -Neutrophils – Most abundant; phagocytize bacteria and debris.

• - Eosinophils – Fight parasites; involved in allergic reactions.

• - Basophils – Release histamine and heparin during inflammation/allergic responses.

 Agranulocytes (lack visible granules):

• - Lymphocytes – B cells (produce antibodies) and T cells (destroy infected or abnormal cells).

• - Monocytes – Become macrophages; phagocytize pathogens, dead cells, and debris.

Hemostasis

-The process of stopping bleeding (blood clotting).
-Involves 3 main steps:

1. =Vascular spasm (blood vessel constriction)

2. =Platelet plug formation

3. =Coagulation (fibrin clot forms)

palmary circuit

Heart → Lungs → Heart

Gas exchange (adds O₂, removes CO₂)

systemic circuit

Heart → Body → Heart

Delivers O₂ and nutrients to tissues, removes wastes

SA Node (Sinoatrial)

Wall of right atrium

Pacemaker: initiates heartbeat (generates impulses)

AV Node (Atrioventricular)

Between atria and ventricles

Slows impulse slightly to allow atria to fully contract

AV Bundle (Bundle of His)

Interventricular septum

Carries impulse from AV node to bundle branches

Bundle Branches

Right & left sides of septum

Direct impulses toward apex of the heart

Purkinje Fibers

Along walls of ventricles

Spread impulse through ventricles → contraction

Mediastinum

The central compartment of the thoracic cavity between the lungs; contains the heart, esophagus, trachea, and major blood vessels.

Pericardial Sac (= Parietal Pericardium)

The tough outer layer of the pericardium that surrounds the heart and anchors it in the mediastinum.

Epicardium (= Visceral Pericardium)

the inner layer of the pericardium that directly covers the surface of the heart; also the outermost layer of the heart wall.

Myocardium

the thick, muscular middle layer of the heart wall; responsible for heart contractions.

Endocardium

The thin inner lining of the heart chambers and valves; smooth surface for blood flow.

Atria (singular: Atrium)

The two upper chambers of the heart (right and left) that receive blood.

Ventricle

The two lower chambers of the heart (right and left) that pump blood out.

Interatrial Sulcus

A shallow groove marking the boundary between the right and left atria on the heart’s surface.

Interventricular Sulcus

A groove on the external surface of the heart marking the boundary between right and left ventricles; contains blood vessels.

Interatrial Septum

The internal wall dividing the right and left atria.

 Interventricular Septum

The thick wall dividing the right and left ventricles.

Right Atrioventricular Valve (Tricuspid Valve)

Between right atrium and right ventricle; prevents backflow into the atrium during ventricular contraction.

Left Atrioventricular Valve (Bicuspid or Mitral Valve)

Between left atrium and left ventricle; prevents backflow into the atrium during ventricular contraction.

Pulmonary Semilunar Valve

Between right ventricle and pulmonary trunk; prevents backflow into the ventricle after contraction.

Aortic Semilunar Valve

Between left ventricle and aorta; prevents backflow into the ventricle after contraction.

 Chordae Tendineae

Tendinous cords that connect AV valve flaps to papillary muscles; prevent valve prolapse.

papillary Muscles

Muscles in the ventricles that pull on chordae tendineae to stabilize AV valves during contraction.

Superior Vena Cava (SVC)

Large vein bringing deoxygenated blood from the upper body to the right atrium.

inferior Vena Cava (IVC)

large vein bringing deoxygenated blood from the lower body to the right atrium.

Pulmonary Arteries

Right and left arteries that carry deoxygenated blood from the right ventricle to the lungs.

Pulmonary Veins

Four veins (2 from each lung) that carry oxygenated blood to the left atrium.

Systole

Phase of the heartbeat when the heart muscle contracts and pumps blood out of the chambers.

Diastole

Phase of the heartbeat when the heart muscle relaxes and the chambers fill with blood.

 Right Coronary Artery (RCA)

Supplies right side of heart.

Left Coronary Artery (LCA)

Supplies left side of heart.

Marginal artery

supplies lateral right ventricle

Posterior interventricular artery

supplies posterior interventricular septum

Circumflex artery

curves around left atrium

Anterior interventricular artery (aka LAD)

supplies anterior septum and walls of both ventricles

 Coronary Sinus

Large vein that collects deoxygenated blood from coronary veins and empties into the right atrium.

Anastomose (Anastomosis)

The connection between two blood vessels, allowing alternative pathways for blood flow (important in coronary circulation for collateral routes).