...types of blood vessels: arteries, veins, and capillaries. Arteries An artery is any of the vessels that, with one exception, carry oxygenated blood and nourishment from the heart to the tissues of the body. The exception, the pulmonary artery, carries oxygen-depleted blood to the lungs for oxygenation and removal of excess carbon dioxide. Arteries are muscular and elastic tubes that must transport blood under a high pressure exerted by the pumping action of the heart. The pulse, which can be felt over an artery lying near the surface of the skin, results from the alternate expansion and contraction of the arterial wall as the beating heart forces blood into the arterial system via the aorta. Veins Veins are similar to arteries but, because they transport blood at a lower pressure, they are not as strong as arteries. Like arteries, veins have three layers: an outer layer of tissue, muscle in the middle, and a smooth inner layer of epithelial cells. However, the layers are thinner, containing less tissue. Veins receive blood from the capillaries after the exchange of oxygen and carbon dioxide has taken place. Therefore, the veins transport waste-rich blood back to the lungs and heart. It is important that the waste-rich blood keeps moving in the proper direction and not be allowed to flow backward. This is accomplished by valves that are located inside the veins. The valves are like gates that only allow traffic to move in one direction. The vein valves are necessary to keep...
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... Using the network of arteries, veins and capillaries, blood carries carbon dioxide to the lungs (for exhalation) and picks up oxygen. From the small intestine, the blood gathers food nutrients and delivers them to every cell. Ima ge des crip Blood Blood consists of: • • • • Red blood cells – to carry oxygen White blood cells – that make up part of the immune system Platelets – needed for clotting Plasma – blood cells, nutrients and wastes float in this liquid. The heart The heart pumps blood around the body. It sits inside the chest, in front of the lungs and slightly to the left side. The heart is actually a double pump made up of four chambers, with the flow of blood going in one direction due to the presence of the heart valves. The contractions of the chambers make the sound of heartbeats. The right side of the heart The right upper chamber (atrium) takes in deoxygenated blood that is loaded with carbon dioxide. The blood is squeezed down into the right lower chamber (ventricle) and taken by an artery to the lungs where the carbon dioxide is replaced with oxygen. The left side of the heart The oxygenated blood travels back to the heart, this time entering the left upper chamber (atrium). It is pumped into the left lower chamber (ventricle) and then into the aorta (an artery). The blood starts its journey around the body once more. Blood vessels Blood vessels have a range of different sizes and structures, depending on their role in the body. Arteries Oxygenated blood is pumped from the heart along...
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...I. INTRODUCTION A. Number of cases/Statistic data of the disease A.1 Statistics Accurate pre-eclampsia statistics are difficult to obtain because the condition ranges from extremely mild to severe. Mild cases are sometimes not included in official figures. Furthermore, mild cases may have no effect on pregnancy, which is why the figures for pre-eclampsia as a whole are higher than for those that actually complicate pregnancies. Around 10% of pregnant women develop pregnancy-induced hypertension (high blood pressure) or pre-eclampsia (high blood pressure with protein in the urine).Worldwide more than four million women per year will develop pre-eclampsia, and over 63,000 maternal deaths are due to pre-eclampsia. Action on Pre-Eclampsia estimates that every year in the UK pre-eclampsia is responsible for the deaths of six mothers and 500 to 600 babies. A 2005 to 2006 study showed a promising fall in the numbers of women developing eclampsia since 1992, from 4.9/10,000 to 2.7/10,000. This has arisen as a result of the introduction of management guidelines for eclampsia and pre-eclampsia. Pre-eclampsia is much more common in first pregnancies, and there is a reduced incidence of pre-eclampsia in the second pregnancy. The risk of women who have had pre-eclampsia developing it again in future pregnancies is 16 percent, and 25 percent if they suffered from severe pre-eclampsia, eclampsia or they delivered pre-term. This rises to 55 percent if their baby was delivered before...
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...This is why medicine is often injected into veins rather than arteries or capillaries. This, in summary, is how the healthy circulatory system works. The heart pumps blood to the lungs where it is oxygenated, then the blood goes back through the heart into the arteries, which push the blood through blood vessels to carry it around the body, and then veins carry the blood back to the heart to be sent to the lungs again. In summary, that is how a healthy circulatory system operates. Atherosclerosis is a slow progressive disease that usually worsens in the victims 30s, but becomes dangerous in the 50s and 60s. Some risk factors that worsen the progression are smoking, high cholesterol, and high blood pressure. The buildups of plaque on the inside of veins and vessels is sometimes described as a plumbing problem. The plaques create a small space for blood to move through, causing backups. It’s harder to drink a milkshake through a coffee straw than it is to drink from a McDonalds straw, isn’t it? The healthy vein is the McDonald’s straw, the coffee straw is the vein with a plaque buildup. If plaques break away from the walls of the vein, it can circulate through the bloodstream as an emboli, which is a...
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...as CO2 that is caused by aerobic respiration so that it can be disposed. Your heart is a fist sized muscle that is located on the left side of your chest and is an involuntary muscle and an adult heart approximately weighs 255grams. The heart is separated by a septum. The left side of the heart is thicker than the right because it has to pump oxygenated blood around the whole body whereas the right side just pumps de-oxygenated blood to the brain. There are 2 inlets and 2 outlets in the heart, there are also 4 valves in the heart that are there to stop the backflow of blood and 4 chambers. The first inlet is called the pulmonary vein. This is the only vein in the body that carry oxygenated blood. The other inlet is the superior and inferior vena cava. The two out lets are called the pulmonary artery and the aorta. The pulmonary artery is the only artery in the body that transports deoxygenated blood in the body. The two upper chambers of the heart are called the atria. The two lower chambers are called the ventricles. The four valves are called the tricuspid, bicuspid, aortic valve and the pulmonary valve. The valves are there in order to stop the backflow of blood. Functions of the Heart The heart has a number of different functions such as delivery of oxygen and nutrients and removal of waste products. The cardiovascular system is broken down into two other parts the systemic and the pulmonary circuit. The systemic circuit is responsible for distributing oxygenated...
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...put ourselves to motivate for every day. If we have no energy in our body, we are dead by now. Glucose is a simple sugar that provides the body with its primary source of energy. This type of sugar comes from digesting carbohydrates into a chemical that the body can easily convert to energy. The carbohydrate is broken down into glucose by enzymes in precise stages that allow energy to be released so that it can be used by the person, when glucose levels in the bloodstream aren't properly regulated, a person can develop a serious condition, such as diabetes. The process involves the random motion of oxygen and glucose from regions of higher concentration First the oxygen must diffuse from the alveolus into the capillaries. It is able to do this because the capillaries are permeable to oxygen. After it...
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...series of the events in order: ~Ingestion: You eat the food. ~Digestion: A series of chemical reactions, whereby you convert the ingested foot to smaller and smaller molecular forms. ~Absorption: Small molecular forms are absorbed through cells of your digestive system and pass into nearby blood or lymphatic vessels ~Transport: Your circulatory system delivers the small molecular nutrients to your body cells. Digestion solves a problem of molecular size. – Many of the foods we ingest have very large molecules –to large to pass across any cell membrane. – In order to get into our bloodstream, molecules must pass through the cell membranes of our intestines and then through the cell membrane of the capillary. Therefore any food we eat must be chemically digested to a suitable size. (Page 165) Digestion allows you to turn molecules into ‘your own’ – Plant cells characteristically store excess carbohydrates in the form of starch whereas animals store excess carbohydrates as glycogen. – Each type of living organism has its own unique set of proteins. – When we digest food molecules we break them down (hydrolyze them) into their smallest components (as in the right-hand column of the table above.) The components then can be reassembled into larger molecules (macromolecules) that are useful to you. The role of enzymes during digestion – Digestive enzymes are added along the way of our alimentary canal....
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...in other vertebrates, blood is confined to a closed system of vessels and is distinct from the liquid (interstitial fluid) that surrounds the cells of the surrounding tissue. Blood is pumped away from the heart and courses through vessels of decreasing diameter that branch into the organs and tissues of the body: these vessels are arteries, arterioles, and capillaries, respectively. At the level of the capillaries, the walls of the vessels are very thin and porous. At the capillary bed, materials carried by the blood are either actively transported across the endothelium or simply diffuse into the interstitial fluid along a concentration gradient. Materials from the interstitial fluid can flow into the capillaries for transport away from the tissues. As blood leaves the capillaries, it travels through vessels of increasing diameter, venules and veins that join one another to complete the circuit back to the heart. Regardless of the materials conveyed in the blood, vessels are characterized by the direction in which they carry material, arteries and arterioles away from the heart and toward the capillaries; veins and venules away from the capillaries and toward the heart. Unlike many vertebrates, birds and mammals possess a four-chambered heart. The evolution of a four-chambered heart is thought to be an adaptation brought about by the high metabolic demands of warm-blooded animals (endotherms). Endotherms expend roughly ten times the amount of energy compared to “cold-blooded”...
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...collects oxygen from the lungs and delivers it to the body. Veins are tubes which form part of the blood circulation system of the body, carrying mainly oxygen-depleted blood towards the heart. Arteries are the blood vessels that deliver oxygen-rich blood from the heart to the tissues of the body. Every artery is a muscular tube lined with smooth tissue and has three layers: * The intima, the inner layer lined by a smooth tissue called endothelium * The media, a layer of muscle that lets arteries handle the high pressures from the heart * The adventitia, connective tissue anchoring arteries to nearby tissues The largest artery is the aorta, the main high-pressure pipeline connected to the heart's left ventricle. The aorta branches into a network of smaller arteries that extend throughout the body. The arteries' smaller branches are called arterioles and capillaries. The pulmonary arteries carry oxygen-poor blood from the heart to the lungs under low pressure, making these arteries unique. Capillary’s are extremely small blood vessel which are located within the tissues of the body, they transport blood from arteries to veins. Capillaries are most abundant in tissues and organs that are metabolically active. For example, muscle tissues and the kidneys have a greater amount of capillary networks than do connective tissues. Capillaries are so small that red blood cells can only travel through them in single file. Capillary walls are thin and are composed of endothelium. Oxygen...
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...blood and blood vessels known as arteries, capillaries and veins. The heart pumps blood throughout your body through the blood vessels. Blood delivers oxygen and nutrients to cells and carries away carbon dioxide and other waste materials. The heart looks like an upside-down pear. It is about the size of your closed fist. It is almost in the middle of your chest. The heart is made of muscle divided into four parts called chambers. The chambers are hollow inside. The two chambers on top are called atria. The chambers on the bottom are called ventricles. The heart also has four valves that let blood in and out of the chambers. The blood vessels are the arteries, veins and capillaries. Arteries are blood vessels that convey blood from the heart to the tissues of the body. Two arteries have direct connection with the heart: (1) the aorta, which, with its branches, conveys oxygenated blood from the left ventricle to every part of the body; and (2) the pulmonary artery, which conveys blood from the right ventricle to the lungs, whence it is returned bearing oxygen to the left side of the heart. The arteries expand and then constrict with each beat of the heart, a rhythmic movement that may be felt as the pulse. Veins, on the other hand, returns blood to the heart from other parts of the body. This false-color electron micrograph shows red blood cells packed into a capillary, the smallest type of blood vessel. Blood flows from the capillaries into veins after oxygen has been exchanged...
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...gases take place (pulmonary respiration) between the alveoli and the blood, through the pulmonary capillaries. At this point the blood will gain oxygen and lose Carbon dioxide. (tortora 2011) It is the function of the red blood cells to transport oxygen around the body. Red blood cells contain a pigment called haemoglobin which attracts oxygen into the cell. (www.hematology.org) From the lungs the blood flows to the heart through four pulmonary veins. It enters into the left atrium and then passes through the mitral valve into the left ventricle. The left ventricle pushes the blood through the aortic valve into the ascending aorta (www.bhf.org.co.uk) Some of the blood flows through coronary arteries into the heart wall whilst the majority divides into separate streams, flowing through systemic arteries throughout the body. Arterial blood is pumped under pressure by the heart through the arteries which divide into smaller arteries called arterioles, when the arterioles enter the tissue they becomes smaller and smaller branches of microscopic capillaries. (www.bhf.org.co.uk) This is when the exchange of gases and nutrients will occur. As the blood flows through the tissue capillaries, the haemoglobin releases oxygen which diffuses into the cells. Carbon dioxide in return diffuses into the blood. The blood is carried back to the heart through systemic veins. From...
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...blood vessels namely arties, veins and capillaries. The primary purpose of the heart is to pump blood at 60 to 80 times per minute to deliver oxygen and nutrients to all body cells. Each day the average heart beats 100 000 times and pumps about 2000 gallons of blood. It is divided into four separate compartments known as atria and ventricles. A healthy heart can continue to beat for many years after some other body organs have worn out. The heart is made of muscle. However heart muscle is slightly different to other muscles in the body. The heart muscle can relax and contract regularly without any nervous stimulation and seems able to go on forever without tiring. An electrocardiogram plots the electrical impulses that control the contraction of heart muscles. Each side of the heart consists of an upper chamber (the atrium) and a lower chamber (the ventricle) the right sided pump contains deoxygenated blood and is separate from the left side which contains oxygenated blood. Each of these two chambers has a major blood vessel that is either leaving or entering the heart. The right pump receives blood from the blood tissues having, off loaded its oxygen, and pumps the blood to the lungs for re-oxygenated. The left pump receives blood from the lungs, fully loaded with oxygen, and distributes it to the body tissue. The blood travels twice through the heart in one circuit around the body. This is known as a double circulation. [pic] Arteries are tubes that carry blood...
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...categories of them, including arteries, capillaries and veins. The basic structure and function of the...
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...Cardiovascular system is transporting system used by the body to export nutrients and oxygen to the body through arteries and remove carbon dioxide by taking it to the lungs through the veins. The walls of capillaries are consist of only one endothelial cell, that is where oxygen and carbon dioxide gets exchanged. The human heart is divided into four chambers; the two upper chambers are called atria and the lower two chambers are called ventricles. The chambers are separated with barriers called septa. The upper chambers are separated with interatrial septum and the lower two ventricles are separated with intraventricular septum. The right side of the heart pumps the deoxygenated blood to the lungs and the left side of the heart pumps the...
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...Human Brain The anatomy of the brain is complex due its intricate structure and function. This amazing organ acts as a control center by receiving, interpreting, and directing sensory information throughout the body. There are three major divisions of the brain. They are the forebrain, the midbrain, and the hindbrain. Anatomy of the Brain: Brain Divisions The forebrain is responsible for a variety of functions including receiving and processing sensory information, thinking, perceiving, producing and understanding language, and controlling motor function. There are two major divisions of forebrain: the diencephalon and the telencephalon. The diencephalon contains structures such as the thalamus and hypothalamus which are responsible for such functions as motor control, relaying sensory information, and controlling autonomic functions. The telencephalon contains the largest part of the brain, the cerebral cortex. Most of the actual information processing in the brain takes place in the cerebral cortex. The midbrain and the hindbrain together make up the brainstem. The midbrain is the portion of the brainstem that connects the hindbrain and the forebrain. This region of the brain is involved in auditory and visual responses as well as motor function. The hindbrain extends from the spinal cord and is composed of the metencephalon and myelencephalon. The metencephalon contains structures such as the pons and cerebellum. These regions assists in maintaining balance...
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