CARDIOVASCULAR SYSTEM (BLOOD VESSELS (Artery (vessel that carries blood…
(vessel that carries blood away from the heart)
any artery stemming from the aorta, moves blood away from heart, largest, proximal to heart, can stretch and recoil to propel blood forward (acts like a pump). Ex. subclavian, brachiocephalic
contains more muscle relative to other arteries, takes blood to organs/organ parts, distal to elastic/conducting arteries, can constrict or dilate to decrease or increase blood flow. Ex. renal, mesenteric, hepatic arteries
smallest of the arteries, one-two layers of smooth muscle only, can constrict or dilate vessels.
most leaky, has large clefts/spaces, large and winding, able to exchange large items (proteins, whole cells) Found in, red bone marrow, liver, spleen
Capillaries with "windows" - pores. wanted in places with high rate of exchange. Found in, small intestine, kidneys, choroid plexus, endocrine glands.
most common and abundant, has somewhat leaky intercellular clefts. Found in CNS, lungs, skin, smooth and skeletal muscle
(vessel that carries blood to the heart)
: smallest of the veins (much like capillaries) one to two layers of smooth muscle
: large and medium in size, have valves to avoid blood pooling, conducts blood back to the heart to be oxygenated, less elastic than arteries
collagen and elastic fibers, thicker in veins, provides strength
smooth muscle with elastic fibers
endothelium (simple squamous epithelium) and in arteries - internal elastic membrane
Sac covered, made of DICT, located from diaphragm to root of large vessels, keeps heart in place and from overfilling. Outermost layer of pericardium
: serous membranes, simple squamous epithelium and areolar connective tissue.
furthest from organ
: on the organ (also called epicardium)
space between parietal and visceral serous pericardium, filled with serous fluid. Fluid is
, reduces friction between heart and other organs/bones
: actual heart cardiac muscle
: Layer that lines inside heart chambers and covers valves. Deep to myocardium.
: Valve that allows blood flow from right atrium into right ventricle. Also prevents back flow of blood.
Valve that allows freshly oxygenated blood to flow from the left atrium into the left ventricle. Also prevents back flow of blood.
Aortic Semilunar Valve:
Valve that allows oxygenated blood to be pumped from left ventricle to ascending aorta to arteries of aortic arch. Prevents back flow from arteries into ventricles.
Pulmonary Semilunar Valve:
Valve that allows blood to pump from right ventricle up pulmonary trunk to be oxygenated in lungs. Prevents back flow into ventricle.
Heart Conduction System
Sinoatrial (SA) Node:
Pacemaker of the heart, sets heart rate. Generates electrical signal to be spread through the atria (myocardium). Contraction of atria,
Signal is sent from nodes to AV bundle, cells that can conduct electricity. Runs along interventricular septum, before branching into left and right.
Left and right, signal is passed from AV bundle and branches into left and right, Signal is first received in apex to contract heart and then works upwards.
: Where bundle branches terminate.
Myocardium Microscopic Anatomy:
Myocardium is made up of striated cardiac muscle, able to contract using sliding filament mechanism. Striations are made up of intercalated discs, these discs contain fasciae adherens and gap juntions.
are desmosome like structures that allow binding to near cells.
allow the transmission of electrical signals/ movement of ions.
: created in red bone marrow in axial skeleton
: blood cells, biconcave shape to increase surface area (easier to exchange O2), loses many organelles, including nucleus before released into blood stream. Contains hemoglobin which is the protein that binds to oxygen
: white blood cells, role in immunity. Includes, neutrophil, eosinophil, basophil, lymphocyte and monocyte
: platelets, these are not cells but pieces of cytoplasm from a large cell called megakarocyte, involved with blood clotting
(helps keep water in the blood vessels/capillaries).
: Immunoglobulins, antibodies, transport for hydrophobic substances.
: involved in blood clotting
: Extracellular matrix/ liquid portion of blood, 90% water, contains more than 100 different molecules (ions, minerals, vitamins, hormones, nutrients - lipids, sugars, amino acids, etc.)