A&p 2
14.How does the contraction and relaxation of the arterioles help to control blood pressure? 15. What does compliance mean? 16. What are the three layers of a vessel? 17. True or false: Only arteries contain a tunica media. 18. Capillaries are interconnected to form _____________. 19. Label all the blood vessels which supply blood to the heart. It is required for you to recognize the orientation of the heart in the picture. For example, what is the artery highlighted in blue in the figure below?
14. Contracting the arterioles increases the blood pressure through decreasing the available volume. Relaxation of the arterioles decreases blood pressure as the volume increases. 15. Stretch with little recoil. 16. Tunica externa (superficial), tunica media, tunica intima (closest to the lumen) 17. False- all vessels contain three layers but in differing proportions. 18. Capillary beds 19. Left coronary artery
20. The aortic arch becomes the __________as it moves inferiorly. 21. What are the three branches off the aortic arch? 22. Label all major branches to/from the heart. 23. What is unique about the Circle of Willis? 24. Know general location of Circle of Willis in relation to its position in the brain. 25. Label all vessels of the Circle of Willis circulation. For example, what vessel is highlighted in blue below?
20. descending aorta 21. Brachiocephalic trunk (right), left common carotid, left subclavian 22. See figure in module 23. The Circle of Willis has a unique feature of providing alternate circulation in case one of the arteries becomes blocked. 24. See figure in module (4.10) 25. Internal carotid (left)
Diseases of the Cardiovascular System
A healthy person can experience some cardiovascular related problems during their normal day. For example, when a person stands perfectly still for a long time, such as a store clerk standing at a cash register, blood tends to pool in the veins. Once the veins are fully distended, they cannot accept blood from the capillaries. Large amounts of plasma are forced out of the thin capillary walls, causing a drop in arterial blood pressure. Once arterial blood pressure drops, blood flow to the brain is reduced and fainting (syncope) results because of the decrease of oxygen supply to the brain
Small arteries called
arterioles are constricted and dilated by muscles controlled by the sympathetic and parasympathetic nervous system, which control blood pressure. Contracting the arterioles increases the blood pressure through decreasing the available volume. Relaxation of the arterioles decreases blood pressure as the volume increases.
Hemoglobin
contains iron that combines loosely with oxygen, helping to carry oxygen in the blood. Red blood cells are manufactured continuously in the red bone marrow of the skull, ribs, vertebrae, and the ends of the long bones.
diastole
efers to relaxation of these chambers. For the heart to function as a pump, it must contract and relax in a cyclical pattern.
Which layer of the heart is continuous with the blood vessels linings?
endocardium
T or F: The left ventricle faces anteriorly, towards the sternum. Describe the location of the heart to the diaphragm.
false
There is a shallow depression on the septum separating the atria called the
fossa ovalis
Granulocytes
have granules in the cytoplasm while agranulocytes do not.
Blood Supply to the Brain
he Circle of Willis is also known as the cerebral arterial circle. See Figure 4.10 to see the Circle of Willis in context and Figure 4.11 to see the Circle of Willis removed from the brain. The Circle of Willis has a unique feature of providing alternate circulation in case one of the arteries becomes blocked. The alternate circulation is important because neurons must be continuously supplied with oxygen or they will die within minutes. Two vertebral arteries rise superiorly along both sides of the spinal cord joining to form the basilar artery at the base of the pons. The basilar artery branches into the left and right posterior cerebral arteries. The posterior communicating arteries connect to the left and right internal carotid arteries. The internal carotid arteries arise from the common carotid arteries in the neck. The internal carotid arteries terminate in the left and right middle cerebral arteries. The anterior cerebral arteries are branches off the middle cerebral arteries. The anterior cerebral arteries are connected by the anterior communicating artery, completing the circle of circulation.
The electrical impulse that controls the cardiac cycle begins at the SA node (sinoatrial node) found in the right atrium
he SA node is known as the "pacemaker" of the heart because it begins the electrical impulses necessary for the cardiac cycle. The SA node is a small mass of specialized cardiac muscle that contains both cardiac and nervous tissue characteristics. The electrical impulse begins at the SA node and spreads through the atria, creating left and right atrial systole.
The bulk of the heart, called the
myocardium
Granulocytes include
neutrophils, eosinophils, and basophils. The two main types of lymphocytes include T-cells and B-cells. The functions of all white blood cells will be discussed in more detail with the lymphatic system.
An infarction
occurs if the blood vessel is entirely blocked by a thrombus or an embolism, causing tissue death in the area supplied by the clogged artery. If unresolved, a person may die from complications. Figure 4.23, below, shows a CT image of a PE in the left lung.
A MYOCARDIAL INFRACTION (HEART ATTACK)
occurs when a portion of the heart muscle dies because of a lack of oxygen. If a coronary artery is partially blocked due to plaque, the individual may suffer from pain called angina pectoris (chest pain), characterized by a radiating pain in the left arm. Often a heart attack is followed by at least one of several other typical symptoms
systole
refers to contraction of heart chambers,
The three types of blood vessels used to transport the blood throughout the body are:
the arteries (which carry blood away from the heart), veins (which carry blood back to the heart), and capillaries (which exchange materials with tissues).
he two-lower pumping (sending) chambers are called
the ventricle
The two upper receiving chambers are called
thew atria
A stationary blood clot is called a thrombus.
If a blood clot dislodges and moves along with blood it is called an embolus.
Blood
Blood is classified as a connective tissue. Blood (Figure 4.12) has two main portions: the liquid portion, called plasma, and the cell portion, called formed elements. Formed elements consist of red blood cells, white blood cells, and platelets. Serum is identical to plasma, except that the clotting proteins have been removed. This is accomplished by letting blood sit in a tube until it clots and then centrifuging the sample to separate the solid and liquid portions of the blood. Serum is used in many laboratory tests.
The branching of arterioles causes formation of even narrower tubes called capillaries
Capillaries are interconnected to form capillary beds, which perform the exchange of materials with the cells of the body. The blood is collected from the capillary beds by small veins called venules, many of which join to form a vein that returns the blood to the heart.
Blood Pressure
Contraction of the left ventricle forces blood into the arteries under pressure
T or F: The cardiovascular system is the study of the organs of the body.
False- it is the study of the heart, blood and vessels.
T or F: The abdominal cavity contains the heart.
False- pericardial cavity inside the thoracic cavity
13. True or False: Veins are primarily responsible for the vessel's ability to control peripheral resistance.
False- the arterioles
Plasma, the liquid portion, has several important functions
First, it helps to buffer the pH of the blood, keeping the pH near 7.4. Plasma also assists in transporting large organic molecules in blood and aids in blood clotting. Finally, plasma maintains the blood's osmotic pressure because of the presence of proteins in the plasma
Each heartbeat, or cardiac cycle, consists of three general phases.
First, the atria contract for about 0.15 seconds while the ventricles relax. Second, the ventricles contract for about 0.30 seconds while the atria relax. Finally, all chambers relax for about 0.40 seconds. The short systole of the atria occurs because the atria send blood only a short distance into the ventricles. The ventricles contract for a longer period to pump blood into the much larger systemic and pulmonary circulatory circuits.
Several factors enable blood to return to the heart from the veins.
First, there is low resistance in the venous walls, meaning that veins can stretch to accurate a larger volume. Second, the presence of internal valves prevents the backward flow of blood. Finally, the assistance of muscular contraction in the limbs and chest enables blood in the veins to maintain a flow rate significant enough to return the blood to the heart.
The impulse then travels through the AV node (atrioventricular node or AV bundle) into the bundle of His
Next, the impulse continues to travel towards the ventricular apex (downward point of the heart). Finally, it travels through the Purkinje fibers, causing the left and right ventricles to contract
Atria
The atria are smaller than and not as muscular as the ventricles, which must force the blood through vessels to distant parts of the body. T
Blood pressure measures the amount of pressure required to stop the flow of blood through an artery, typically the brachial artery.
The bulb portion is squeezed to inflate the bladder with air. The bladder is held in place over an artery by the cuff. The manometer displays the pressure in millimeters of mercury. The pressure inside the bladder is slowly released by turning the valve, emptying the bladder of air and allowing blood to flow through the artery again.
What is the purpose of the mitral valve?
The mitral valve (bicuspid) controls the flow of blood from the left atrium into the left ventricle.
Red Blood Cells
Red blood cells (erythrocytes) are small biconcave disks that carry oxygen (Figure 4.13). They are the most abundant cell in the blood. There are 4 million to 6 million red blood cells per 1.0 mm3 of whole blood. Each red blood cells contains about 250 million hemoglobin molecules
Mature red blood cells are anucleate, or without a nucleus.
Red blood cells must lose their nucleus and synthesize hemoglobin before they are released into blood. Red blood cells live for about 120 days and then are destroyed in the liver and spleen. When red blood cells are destroyed, the hemoglobin is released so that the iron can be recycled and returned to the red bone marrow for reuse. The heme portions of the molecules undergo chemical degradation and are excreted by the liver as bile pigments.
Systolic pressure
Results from blood being forced into the arteries during ventricular systole.
Label all heart chambers and valves.
See figures in module.
The nervous system and endocrine systems regulate the heart rate (number of beats per minute)
Through neurotransmitters such as norepinephrine and acetylcholine. The interaction of the nervous and endocrine systems enables the heart to change blood pressure with emotional and physical stressors.
T or F: The tough, thick sac that encloses the heart and anchors it to the diagram is the pericardium.
True
What is the purpose of veins?
Veins carry blood back to the heart.
The two lower chambers of the heart are called _______________.
Ventricles
26. True or False: Blood is classified as epithelial tissue. 27. What is the cell portion of blood called? 28. How is serum made? 29. True or false: Osmotic pressure pushes fluid into the tissues. 30. What is the average pH of blood? 31. What is the shape of red blood cells? 32. What is the purpose of hemoglobin? 33. What is average life span of a red blood cell? 34. True or False: Once it dies, all portions of the red blood cell is destroyed and excreted. 35. True or False: White blood cells are smaller than red blood cells. 36. What are the contents of pus? 37. What are the three main types of white blood cells? 38. What are platelets? 39. What is the coagulation cascade? 40. What converts prothrombin to thrombin? 41. What is the purpose of fibrin? 42. What is plasmin? 43. Identify histological pictures of blood cells in the module.
26. False- connective tissue 27. Formed elements 28. Letting blood sit in a tube until it clots and then centrifuging the sample to separate the solid and liquid portions of the blood .29. False-pushes fluid into the circulatory system 30. 7.4 31. Biconcave disks 32. To carry oxygen, which loosely combines with iron inside the hemoglobin 33. 120 days 34. False- the iron can be recycled and returned to the red bone marrow. 35. False 36. The thick, yellowish fluid called pus contains a large proportion of dead white blood cells that have fought the infection and then undergo cell death. 37. Granulocytes, agranulocytes and lymphocytes. 38. Platelets (thrombocytes) are involved in the process of blood clotting, or coagulation. Platelets are not true "cells", but instead are fragments of a large bone marrow predecessor called a megakaryocyte. 39. A series of events to start the blood clotting mechanism 40. Prothrombin activator 41. Fibrin threads wind around the platelet plug in the damaged area of the blood vessel and provide the framework for the clot. 42. As soon as blood vessel repair is initiated, an enzyme called plasmin destroys the fibrin network and restores the fluidity of plasma. 43. See pictures within module.
44. What are the pulmonary and system circuits? 45. What are the inferior and superior vena cavae? 46. The __________are the only arteries in the body carrying deoxygenated blood away from the heart. 47. The pulmonary veins return blood to the ______. 48. Trace the step by step blood flow through the heart by drawing your own diagram. Make any notes here: 49. Diastole refers to ______. 50. Systole refers to ______ . 51. True or False: each heartbeat typically lasts longer than 2 seconds. 52. True of False: The atria contraction time is much longer than the ventricles. 53. True or False: The heart sounds are of the valves opening. 54. How does the nervous system and endocrine system interact with the heart? 55. Label the parts of a sphygmomanometer. 56. What is the purpose of the blub? 57. What is the purpose of valves inside the veins? 58. What portion is the pacemaker of the heart? 59. Following the bundle of His, where does the electrical impulse travel next? 60. The impulse of the SA node causes contraction of the ______. 61. What is an EKG? 62. What is the P-wave?
44. The right circuit is called the pulmonary circuit, sending deoxygenated blood to the lungs to be oxygenated. The left circuit is called the systemic circuit, sending the oxygenated blood to the cells. 45. They return deoxygenated blood to the right atrium. 46. pulmonary arteries. 47. Left atrium. 48. See figure in module. 49. Relaxation 50. Contraction 51. False (less than 1). 52. False 53. False 54. The heart rate is regulated by the nervous system and endocrine system which can increase or decrease the rate of the heartbeat and blood pressure. 55. See figure in module. 56. The bulb portion is squeezed to inflate the bladder with air. 57. Prevents the backward flow of blood. 58. SA node 59. Purkinje fibers 60. Atria 61. A device used to measure electrical impulses in the heart 62. Atrial depolarization and atrial systole
63. What is edema? 64. What is pulmonary edema? 65. Hypertension is blood pressure significantly higher than: 66. What is atherosclerosis? 67. What is the difference between a thrombus and an embolus? 68. PE is an abbreviation for: 69. What is the medial term for a heart attack? 70. What is angina pectoris? 71. Name at least one other heart attack symptom: 72. Streptokinase is a drug given to______. 73. Name two surgical procedures available to clear clogged arteries.
63. Fluid accumulation 64. Fluid in the lungs 65. 120/80 66. Accumulation of soft masses of fatty materials inside the arteries. 67. A stationary blood clot is called a thrombus. If a blood clot dislodges and moves along with blood it is called an embolus. 68. Embolism 69. Myocardial infarction 70. Chest pain (in a heart attack, pain often radiates down the left arm) 71. Lightheadedness. 72. Dissolve a blood clot 73. Angioplasty, coronary artery bypass
Surgical procedures are also available to clear clogged arteries.
Angioplasty is a procedure where a surgeon threads a plastic tube into the artery of an arm or a leg. The tube is then guided through the blood vessel toward the heart. When the tube reaches the segment clogged by plaque in a coronary artery, the balloon attached to the end of the tube is inflated, forcing the vessel open (Figure 4.25).Angioplasty is a procedure where a surgeon threads a plastic tube into the artery of an arm or a leg. The tube is then guided through the blood vessel toward the heart. When the tube reaches the segment clogged by plaque in a coronary artery, the balloon attached to the end of the tube is inflated, forcing the vessel open (Figure 4.25). During this operation, a segment of another blood vessel from the patient's body is stitched to one end of the aorta and the other end to a coronary artery past the point of obstruction. Once the heart is exposed, some physicians may also use lasers to open clogged coronary vessels.
The two upper chambers of the heart are called_____________.
Atria
What is the purpose of the fossa ovalis in a fetus?
It allows fetal blood to move directly from right to left atrium, bypassing the undeveloped lungs. The fossa ovalis closes during birth so that the lungs can receive oxygen once the baby is born.
Blood Supply to the Body:
Once the blood leaves the heart, it leaves through the aorta and spreads throughout the body. The aortic arch (Figure 4.8) turns posteriorly and becomes the descending aorta. The thoracic aorta is in the thoracic cavity above the diaphragm. The descending aorta becomes the abdominal aorta below the diaphragm. The inferior vena cava returns deoxygenated blood from the lower body, and the superior vena cava returns blood to the heart from the upper body The major vessels are typically named for the region of their location or where it supplies blood. For example, the brachiocephalic trunk (Figure 4.9) is the first branch off the aortic arch. The brachiocephalic trunk supplies blood to the right arm and neck. (Brachio means arm, and cephalic means relating to the head.) Some major arteries and veins have matching names if running together in a parallel location. For example, the right and left subclavian arteries and the right and left subclavian veins parallel each other on the left and right sides of the body. The figure below labels the major branches to and from the heart
The thick, yellowish fluid called
PUS contains a large proportion of dead white blood cells that have fought the infection and then undergo cell death.
Atrial depolarization (active firing of a nerve impulse) and atrial systole are denoted as the P-wave
Ventricular depolarization and ventricular systole are denoted as the QRS complex. Ventricular repolarization (returning to rest) and ventricular diastole are denoted as a T-wave (Figure 4.20). There is no way to note the repolarization of the atria, as its activity is lost within the QRS complex.
cardiovascular system
The cardiovascular system includes the study of the muscular heart, blood vessels, and blood.
cardiovascular system
The cardiovascular system is a closed circulatory system because the fluid contents are pumped from the heart throughout the body and back to the heart.
Describe the location of the heart to the diaphragm.
The diaphragm is located inferior to the heart. (The heart is located superior to the diaphragm.)
When the heart beats, the heart sounds are called lub-dub sounds as the valves of the heart close.
The first lub sound is heard when the atrioventricular (bicuspid and tricuspid) valves close. The dub is heard when the semilunar valves close. The heart sounds can be heard using a stethoscope
cardiovascular system
The functions of the cardiovascular system include transporting gases, nutrients, and wastes throughout the body. Secondly, the cardiovascular system prevents the loss of blood from ruptured vessels through clotting mechanisms. Finally, the cardiovascular system fights the invasion of the body by foreign pathogens.
The Cardiac Cycle
The heart contracts, or beats, about seventy times a minute, and each heartbeat lasts about 0.85 seconds.
Electrical Impulses
The heart has an elaborate electrical system that is responsible for maintaining its intrinsic rhythmic abilities (Figure 4.19). The contractions of the cardiac muscle begin within the heart muscle itself, making it somewhat independent of any nerve supply from the central nervous system. If removed from the body, the heart can continue to beat on its own with proper nutrients and oxygen.
heart
The heart is a fist-sized cone-shaped muscular organ located in the pericardial cavity in the anterior portion of the mediastinum between the lungs
Blood follows a one-way path through the heart, lungs, and body
The pathway is best described as it returns (in a deoxygenated form) from the cells of the body entering the heart. Two large veins called the inferior and superior vena cavae return deoxygenated blood to the right atrium (Figure 4.17). From the right atrium blood flows through the tricuspid valve into the right ventricle. The right ventricle pumps blood through the pulmonary valve into the pulmonary arteries to the lungs. The pulmonary arteries are the only arteries in the body carrying deoxygenated blood away from the heart. After the blood is oxygenated in the capillary bed of the lungs (also losing its carbon dioxide), it is carried by the pulmonary veins to the heart entering the left atrium. This oxygenated blood flows through the bicuspid valve (mitral valve) into the left ventricle, which pumps it through the aortic valve into the aorta, the largest vessel in the body. The aortic arch turns posteriorly, carrying oxygenated blood to supply the cells of all body tissue with oxygen and nutrients. Deoxygenated blood is then returned to the right atrium through the vena cavae, which completes the circuit
The heart has four one-way valves that regulate the flow of blood
The pulmonary valve controls the flow leaving the right ventricle into the pulmonary trunk. The aortic valve controls the flow of blood out of the left ventricle into the aorta. The aortic valve is stronger than the pulmonary valve because of the increased blood pressure needed to send blood pumping to the entire body. The mitral valve (bicuspid) controls the flow of blood from the left atrium into the left ventricle. The tricuspid valve controls the flow of blood from the right atrium into the right ventricle.
Blood Supply to the Heart
There are also two artery systems (left and right coronary arteries), which arise from the base of the aorta and supply oxygen and nutrients to the heart tissues (Figure 4.6). The left coronary artery runs toward the left side of the heart and divides into the anterior interventricular branch and the circumflex branch. The anterior interventricular branch supplies blood to both ventricles. The circumflex branch supplies the left atrium and left ventricle (Figure 4.6). The right coronary artery runs toward the right side of the heart and divides into the posterior interventricular artery and the marginal artery, which supply the right atrium and right ventricle
fossa ovalis
There is a shallow depression on the septum separating the atria called the.It allows fetal blood to move directly from right to left atrium, bypassing the undeveloped lungs. The fossa ovalis closes during birth so that the lungs can receive oxygen once the baby is born.
Blood flow through the heart is controlled by the four heart valves.
These valves assure that the blood flows in one direction: forward from vessels into the atria, into the ventricles, and then out of the ventricles. The heart is a double pump because it has two circuits. The right circuit is called the pulmonary circuit, and it sends deoxygenated blood to the lungs to be oxygenated. The left circuit is called the systemic circuit, and it sends the oxygenated blood from the heart to the cells of the body
White Blood Cells
White blood cells are also called leukocytes (Figure 4.14). White blood cells differ from red blood cells in several ways: They are larger, have a relatively large nucleus, and lack hemoglobin.
There are several different types of white blood cells
White blood cells are divided into three groups: granulocytes, agranulocytes, and lymphocytes.
Blood clotting also needs the involvement of fibrinogen,
a protein manufactured by the liver that freely floats in the blood. Thrombin helps to convert fibrinogen to activated fibrin. Fibrin threads wind around the platelet plug in the damaged area of the blood vessel and provide the framework for the clot. Red blood cells also become trapped within the fibrin threads, which make the clot appear red. The network of fibrin and platelets work together to form a platelet plug to stop the bleeding but is present only temporarily. As soon as blood vessel repair is initiated, an enzyme called plasmin destroys the fibrin network and restores the fluidity of plasma. Malfunctions or deficiencies in this clotting cascade can lead to a variety of clotting diseases.
Arteries
are elastic, thick-walled vessels that can expand and contract to accommodate the larger blood volume flowing from the heart at the end of each heartbeat.
Platelets (thrombocytes)
are involved in the process of blood clotting, or coagulation. Platelets (Figure 4.16) are not true "cells," rather they are fragments of a large bone marrow predecessor called a megakaryocyte. When a blood vessel is broken, platelets help stop bleeding by sticking to the edges of the wound and begin to clot the opening
Arterioles
are the vessels primarily responsible for providing differing levels of peripheral resistance (varying blood pressure) to blood flow depending on the external and internal conditions affecting the body.
Veins
are thinner-walled vessels that are under less pressure from the heart. For this reason, veins do not have pulses. Arteries, not veins, have palpable (able to be felt) pulses. Veins have internal valves that open toward the heart and close at the end of a heartbeat to prevent blood from flowing backward as the blood is returned to the heart. Veins have compliance, which means stretch with little recoil. Because of their compliance, veins have the largest amount of blood in the cardiovascular system.
The opening in the center of a vessel is called the lumen.
arteries and veins throughout the body contain three layers: the tunica externa, tunica media, and tunica intima. The thickness of the layers depends on the location in the body. The tunica externa (adventitia) is the most superficial layer of a vessel, which helps to anchor the vessel to the surrounding structures. The tunica media is the middle muscular layer of a vessel has an external elastic membrane, a layer of smooth muscle, and a layer of internal elastic membrane. The tunica intima layer of a vessel contains a layer of subendothelial tissue and a layer of endothelium.
When microorganisms enter the body due to an injury, the body responds through the
inflammatory response because there is swelling and reddening at the injured site. The swelling and redness is due to an increase in blood flow to the injured site, which helps to deliver the immune defense cells. The white blood cells squeeze through the capillary walls and enter the tissue fluid, where they destroy any foreign materia
The EKG, or ECG, (electrocardiogram)
is a device used to measure electrical impulses in the heart (Figure 4.20). Different parts of the ECG tracing represent the rhythmic electrical impulses and corresponding mechanical events in the heart. Medical personnel commonly use ECGs to monitor and diagnose patient conditions.
A thromboembolism
is an embolus that becomes lodged in a vessel as it travels. If a thromboembolism lodges in a vessel supplying a vital organ of the body like the brain, heart, or lungs, serious complications or sudden death may occur
One cause of hypertension
is atherosclerosis, or an accumulation of soft masses of fatty materials, often cholesterol, inside arteries (Figure 4.22). These deposits, called plaque, accumulate beneath the inner linings of arteries. As plaque continues to build up it tends to protrude into the vessel, interfering with normal blood flow. Plaque can cause a blood clot to form on the irregular arterial wall (Figure 4.22). The plaque may stop blood flow in the immediate area or a clot can dislodge and travel, clogging a smaller artery in its path.
the myocardium
is composed mainly of cardiac muscle and is the layer that contracts.
Hypertension
is defined as the condition when the systolic and diastolic pressures are significantly higher than 120/80 mm Hg. Hypertension is sometimes called a "silent killer" because it may not be detected until a stroke or heart attack occurs. It is important to have regular blood pressure checks and to adopt a lifestyle that protects against the development of hypertension.
A pulmonary thromboembolism (PE
is the blockage of a major artery in the lungs, causing shortness of breath and angina (chest pain).
Osmotic pressure
is the net pressure in the blood that moves fluid from the tissues into the circulatory system. Osmotic pressure is driven by proteins in the plasma that remain in the capillaries. In the case of blood at the capillaries, water has an automatic tendency to flow towards the proteins, pulling fluids back into the circulatory system.
Diastolic pressure
is the pressure in the arteries during ventricular diastole
A stethoscope
is used to listen to the first and last sounds of the blood flow displayed on the manometer. A blood pressure reading consists of two numbers, for example, 120/80—which represents systolic and diastolic pressures, respectively.
The heart has four chambers separated into a right and left set by a partition called the
septum
Blood pressure is measured with a piece of medical equipment called a
sphygmomanometer
Medical treatment for a thromboembolism includes two drugs that may be given intravenously to dissolve a clot:
streptokinase (normally produced by bacteria) and t-PA, which is genetically engineered. Both drugs convert plasminogen, a molecule found in blood, into plasmin, an enzyme that dissolves blood clots. If a person has symptoms of angina or a thrombolytic stroke, an anticoagulant drug such as aspirin may be given by the emergency response team. Aspirin reduces the coagulation of platelets and therefore lowers the probability that a clot will form.
Osmotic pressure opposes the hydrostatic pressure of the blood
which pushes fluid into the tissues by the pressure of blood pumping from the heart. It is important for the body's homeostasis to have an ongoing balance between osmotic and hydrostatic pressures so that fluids flow into the tissues and then return to the circulatory system.
