Cardiovascular System

Heart

Blood Vessels

Blood

Capillaries

Veins

Arteries

Fenestrated

Sinusoidal

Continuous

Has "windows" (pores) for high rate of exchange such as in small intestine, kidneys, choroid plexus, capillaries in synovial membranes and endocrine glands.

Most common. In central nervous system, skin, smooth/ skeletal muscle, etc. Has intercellular clefts (gaps) and is kind of leaky. Intercellular clefts are gaps made by unjoined membrane without tight junctions and some desmosomes.

Large, winding. Wide, leaky capillaries with few cell junctions and open intercellular clefts that allows large items such as protein, and whole cells to pass through. Is in liver (proteins) and spleen (whole cells).

Systemic

Superficial

Pulmonary

Deep

Carries oxygen rich blood from the lungs to the heart.

Takes oxygen poor blood to the right atrium.

More superficial and nearest skin without similar artery

Deep within muscle tissue with similar artery

Plasma

Cells

Liquid. 90% water, and more than 110 different molecules, ions, minerals, vitamins, and hormones.

Erythrocytes (Red Blood Cells)

Thrombocytes (Platelets)

Leukocytes (White Blood Cells)

Monocytes

Lymphocytes

Basophils

Eosinophils

Neutrophils

Pericardial Membranes

Elastic

Loses organelles and nucleus before being released into the blood stream. Biconcave makes them have more surface area so it can easily pick up and give oxygen. Has hemoglobin to bind with oxygen.

Not cells, but pieces of cytoplasm from megakaryocytes. Clots when with fibrinogen.

Most abundant WBC (40%-70%). First to respond against bacterial infections. Phagocyte.

1%-3% of WBC. Involved with allergy and asthma functions while also helping with immunity.Acidic. Granulocyte.

Least common WBC (0.5%-1%). Large and helps with inflammatory responses, such as making histamine and serotonin which inflames. Makes heparin which stops blood clotting. Granulocyte.

Includes T, B, and Natural Killer cells, and are found in lymph. Involved with immune system of vertebrate.

Three types (Classic, Non-classic, and Intermediate). Can perform phagocytosis and destroy infected host cells. Involved in immune system of vertebrate.

Muscular/Distributing

Arteriole

Largest arteries near the heart. 1 cm.- 2.5 cm lumen, Low resistance from large lumen allows better conducting between heart and muscular arteries. Moves blood away from heart. Thick elastic wall of tunica media and few smooth muscle.

Distal to elastic arteries. More smooth muscle relative to size than other arteries. Lumen is 0.3 mm to 1 cm. Takes blood to and supplies organs. Can constrict or dilate to decrease or increase blood flow, respectively.

Smallest artery with lumen being 10 micrometer to 0.3 mm. Only 1-2 layers of smooth muscle in tunica media. Can constrict or dilate. Small arterioles lead to capillaries.

Venules

Smallest veins similar to capillaries with only 1-2 layer of smooth muscle. Smallest venules are considered postcapillary venules and has an endothelium consisting of pericytes.

Layers of Heart Wall

Microscopic Anatomy of Myocardium

Heart Valves

Conduction of Heart

Serous Pericardium (Serous Membranes)

Pericardial Cavity

Fibrous Pericardium

Made of dense irregular connective

Parietal Pericardium

Filled with serous fluid to reduce friction.

Visceral Pericardium

Made of simple squamous epithelium and areolar connective tissue.

Endocardium

Sarcoplasmic Reticulum

Sinoatrial Node

Myocardium

Epicardium

Simple squamous epithelium and areolar connective tissue. Covers valves.

Muscle of heart.

(Serous membrane) Visceral pericardium.

Gap Junctions

Intercalated Discs

Space where electrical signals and movement of ions occur.

Fascia adherens are desmosome- like structures that works to anchor non-epithelium tissue together

Has T-Tubules but no terminal cisterns.

Atrioventricular Valves

Aortic Semilunar Valve

Pulmonary Semilunar Valve

Mitral Valve (Bicuspid)

Tricuspid Valve

Between left atrium and ventricle and is connected to chordae tendoneae which is connected to papillary muscle. Prevents backflow of blood from right atrium to right ventricle.

Between right atrium and ventricle and is connected to chordae tendoneae which is connected to papillary muscle. Prevents backflow of blood from left atrium to left ventricle.

Between pulmonary trunk and right ventricle which prevents backflow back into ventricle from arteries.

Between aorta and left ventricle which prevents backflow back into ventricle from arteries

"Pacemaker" which sets the heartrate and generates electrical signals that spread through gap junctions in myocardium of atria to create contraction of atria. Signal then goes to atrioventricular node

Atroventricular Node

Short delay to allow ventricles to fill then to atrioventricular bundle

Atroventricular Bundle

Has branches to left and right in myocardium of interventricular septum that activates the ventricles on their respective sides. The signal then goes to Parkinje fibers.