The Circulatory System Flashcards
Pumps and directs blood cells and substances carried in blood to all tissues of the body.
Circulatory system
Propels blood through the system
Heart
Carry blood from the heart to the tissues
Arteries
Sites of O2 and CO2 nutrient, and waste product exchange between blood and tissues
Capillaries
The capillaries form a complex network of thin, anastomosing tubules called _______
Microvasculature
Carry blood towards the heart to be pumped again
Veins
Where blood is oxygenated in the lungs
Pulmonary circulation
Where blood brings nutrients and removes wastes in tissues throughout the body
Systemic circulation
A simple squamous epithelium that lines the internal surface of all components of the blood and lymphatic systems
Endothelium
Contracts rhythmically, with pumping the blood through the circulatory system
Cardiac muscle
The circulatory system consists of the …
Heart
Arteries
Veins
Microvascular beds
Consists typically of contractile cardiac muscle fibers.
Myocardium
T or F. Because a strong force is required to pump blood through the systemic and pulmonary circulations, the myocardium is much thicker in the walls of the atrial walls than in the blood walls of the ventricles.
False. Myocardium is much thicker in the walls of the ventricles, particularly the left, than in the atrial walls
This separates the musculature of the atria from that of the ventricle, forms part or the interventricular and interatrial septa, and extends int the valve cusps and the chordae tendineae to which they are attached.
Cardiac skeleton
It surrounds, anchors, and support all heart valves
Cardiac skeleton
It provides firm points of insertion for cardiac muscle in the atria and ventricles
Cardiac skeleton
Its helps coordinate the heartbeat by acting as electrical insulation between atria and ventricles
Cardiac skeleton
This makes up the impulse conducting system of the heart that is specialized to generate and conduct waves of depolarization which stimulate rhythmic contractions in adjacent myocardial fibers.
Modified cardiac muscle cells
Pacemaker
Sinoatrial node
These are pale-staining fibers, larger than the adjacent contractile fibers, with sparse, peripheral myo-fibrils, and much glycogen
Purkinje fibers
A simple squamous mesothelium supported by a layer of loose connective tissue containing blood vessels and nerves.
Epicardium
Membrane surrounding the heart
Pericardium
A lubricant fluid that prevents friction within the percardium.
Percardial fluid
A fibrous network that serves as an attachment for the cardiac skeleton and various valve
Chordae tendineae
These are necessary for the contraction of the heart
Atrioventricular (AV) bundle
Conducting System
a. SA node - AV node - Subendocardial conducting network - AV bundle
b. AV node - SA node - AV bundle - Subendocardial conducting network
c. SA node - AV node - AV bundle - Subendocardial conducting network
C. SA node - AV node - AV bundle - Subendocardial conducting network
Initiates the electrical impulse for contraction (heartbeat) and spreads it through the ventricular myocardium
cardiac conducting system
Core of the valve and contains fibrous extensions from the dense irregular connective tissue of the skeletal rings of the heart.
Fibrosa
Acts as a shock absorber to dampen vibration associated with the cosing of the valve
Spongiosa
Fibrous threadlike chords also covered w/ endothelium
Ventricularis
Specialized epithelium that acts as a semipermeable barrier between two major internal compartments: the blood and the interstitial tissue fluid.
Endothelium
A surface presented by the endothelium which blood will not clot and actively secrete agents that control local clot formation.
nonthrombogenic surface
In venules ____________ cells induce specific white blood cells to stop and undergo transendothelial migration at sites of injury or infection
endothelial
Storage granules of endothelial cells and important in keeping the blood from clotting
Weibel-Palade bodies
Stimulate formation of the vascular system from embryonic mesenchyme (vasculogenesis)
Vascular Endothelial Growth Factor (VEGF)
Promote capillary sprouting and outgrowth from small existing vessels (angiogenesis) during normal growth, during tissue repair and regeneration
Vascular Endothelium Growth Factor (VEGF)
T or F. Smooth muscles occur in the walls of al vessels smaller than capillaries and are arranged helically in layers.
False. Smooth muscles occur in the walls of al vessels LARGER than capillaries and are arranged helically in layers.
Innermost layer of the vessel
Tunica Intima
The basal lamina of the endothelial cells in the tunica intima has a thin extracellular layer composed chiefly of …
collagen
proteoglycans
glycoproteins
A sheet like layer or a lamina of fenestrated elastic material contained by the subendothelial layer of the arteries and arterioles which allows expansion especially during high blood pressure.
internal elastic membrane
The tunica adventitia is composed primarily of what type of collagenous tissue?
Type 1
Blood supply of our blood vessel
Vasa vasorum
Nerve supply of the blood vessel
Nervi vascularis
An artery has a thicker media and relatively narrow lumen intended for the distribution of _______.
blood
A vein has a larger lumen and its adventitia is the thickest layer intended for the distribution of ________ towards the tissue.
deoxygenated blood
Its major role is to carry blood to smaller arteries
Elastic arteries
The most prominent feature of elastic arteries
A. Tunica intima
B. Tunica media
C. Tunica adventitia
B. Tunica media
Its number in the arteries contribute to their important function of making the blood flow more uniform.
elastic laminae
conducting arteries
Elastic arteries
Distributing arteries
Muscular arteries
These distribute blood to the oragns and help regulate blood pressure by contracting or relaxing the smooth muscle in the media.
Muscular arteries
smallest arteries branch
arterioles
Refers to when blood is moved through the arteries forcefully and the elastin is stretched, distending the wall within the limit set by the wall’s collagen.
Ventricular contraction (systole)
Refers to when ventricular pressure drops to a low level, but the elastin rebounds passively, helping to maintain arterial pressure.
Ventricular relaxation (diastole)
These prevent backflow of blood into the heart so the rebound continues the blood flow away from the heart.
aortic and pulmonary valves
Flow regulators of the capillary beds
Arterioles
Refers to the slight thickening of the smooth muscle at the origin of a capillary bed from an arteriole.
Precapillary sphincter
Form blood vascular networks that allow fluids containing gases, metabolities, and waste products to move through their thin walls.
Capillaries
Permit and regulate metabolic exchange between blood and surrounding tissues
Capillaries
The following are the histologic types of capillaries, except:
A. Continuous
B. Fenestrated
C. Discontinuous
D. NOTA
D. NOTA
A histologic type of capillary that provide for continuity along the endothelium and well-regulated metabolic exchange across the cells.
continuous capillaries
Which among the following is the most common type of capillary
A. Continuous
B. Fenestrated
C. Discontinuous
D. NOTA
A. continuous
This capillary histologic type is found in organs with rapid interchange of substances between tissues and the blood, such as the kidneys, intestine, choroid plexus, and endocrine glands
Fenestrated capillaries
Commonly called sinusoids
Discontinuous capillaries
Collect blood from the capillary network
Post capillary venules
Provide vascular support and promote stability of capillaries and postcapillary venules
Pericytes (Rouget Cells/Mural Cells)
Also called anastomes
Arteriovenous (AV) shunts
It directly connects the arterial and venous systems and temporarily bypass capillaries and also direct routes between arteries and veins that divert blood from the capillaries.
Arteriovenous (AV) shunts
Capillary beds are supplied by _______ and drain into venules, but alternative pathways are found in certain organs.
arterioles
Special type of blood vessels that does not follow the usual structure of the former discuss blood vasculatures.
Atypical blood vessels
Blood vessels that supplies nutrients and oxygen to the heart
Coronary arteries
Hardening of arteries
Atherosclerosis
Refers to venous channels in the cranial cavity and broad spaces within the dura mater that are lined with endothelial cells and devoid of smooth muscles
Dural venous sinuses
Used for coronary artery bypass graft where the arterial grafts are not available so medically this is made use of instead
great saphinous vein
Excess interstitial fluid
lymph
Originate as closed-ended vessels consisting of a single layer of very thin endothelial cells on an incomplete basal.
Lymphatic capillaries (lymphatics)
Resembles that of veins except with thinner walls and no distinct separation among tunics
Lymphatic vessels
Where lymph is processed by cells of the immune system
lymph nodes
direction of lymph flow
unidirectional
T or F. Contraction of the smooth muscle in the walls of larger lymphatic vessel also helps propel lymph toward the heart.
True
Openings between endothelial cells are held in place by _______ containing elastin and are covered by extensions of the endothelial cells.
anchoring filaments
Swelling in the lymphatic drainage
lymphedema
