1. Name: LEVVA SOFIA Number: 27108 E-mail: s_levva@hotmail.com2. Name: KOULINA ANASTASIA Number: 27076 E-mail: tkoulina@in.com

BODY SYSTEM: CARDIOVASCULAR SYSTEM

Student 1: Levva Sofia

Question 1: How does the circulatory system work?

Answer: Heart and circulatory system make up the cardiovascular system. The heart, works as a pump that pushes blood to the organs, tissues, and cells of the body. The one-way circulatory system carries blood to all parts of the body (including the heart itself) and then back to the heart, through a complex network of elastic tubes, called vessels. The body’s circulation has two parts, with the heart acting as a double pump. The pumping of the heart forces the blood on its journey. Blood from the right side pump is dark red (bluish) and low in oxygen. It travels along pulmonary artery to the lungs where it receives fresh supplies of oxygen. Then, it flows along pulmonary veins back to the heart’s left side pump. Blood leaves the left side of the heart and travels through arteries, which finally branch into capillaries. Capillaries move the blood back through wider vessels called venules. Venules eventually join to form veins. The blood then travels in veins back to the right side of the heart, and the whole process begins again. The body’s circulatory system has three distinct parts, as they referred below. Each part must be working independently in order for them to all work together.

Pulmonary circulation

Pulmonary circulation is the movement of blood from the heart, to the lungs, and then back to the heart again. Throughout two large veins called vena cavae, all the veins of the

body bring waste-rich blood back to the heart entering the right atrium. The right atrium fills with the blood and then contracts, pushing the blood through a one-way valve, the tricuspid valve, into the right ventricle. The right ventricle fills and then contracts, pushing the blood into the pulmonary artery which leads to the lungs. At the same time, tricuspid and mitral valves are closed. In the lung capillaries, takes place the exchange of carbon dioxide and oxygen. The fresh, oxygen-rich blood returns to the heart, re-entering through the left atrium throughout the pulmonary veins. The oxygen-rich blood then passes through mitral valve (a one-way valve) into the left ventricle where it will exit the heart through aorta. The left ventricle’s contraction forces the blood into the aorta and then begins its journey throughout the body. The one-way valves are important for preventing any backward flow of blood. The circulatory system is a network of one-way streets. If blood started flowing the wrong way, the blood gases (oxygen and carbon dioxide) might mix, causing a serious threat to your body.

Coronary circulation While the circulatory system is busy providing oxygen and nourishment to every cell of the body, heart which works hardest of all, needs oxygen-rich blood to survive. Coronary circulation refers to the movement of blood through the tissues of the heart. Blood is supplied to the heart by its own vascular system, the coronary arteries.

The aorta branches off into two main coronary arteries. These branch off into smaller arteries, which supply oxygen-rich blood to the entire heart muscle. The heart tissue receives nourishment through the capillaries located in the heart. The right coronary artery supplies blood mainly to the right heart. The right side of the heart is smaller because it pumps blood only to the lungs. The left coronary artery, which branches into the left anterior descending artery and the

circumflex artery, supplies blood to the left side of the heart. The left side of the heart is larger and more muscular because it pumps blood to the rest of the body. Serious heart damage may occur if the heart tissue does not receive a normal supply of food and oxygen.

Systemic circulation

Systemic circulation supplies nourishment to all the tissue of the human body, with the exception of the heart and lungs. The blood vessels are responsible for the delivery of oxygen and nutrients to the tissue. The forceful contraction of the heart’s left ventricle forces the oxygen-rich blood into the aorta which then branches into many smaller arteries which run throughout the body. The blood enters the capillaries where the oxygen and nutrients are released. The waste products are collected and the blood which transfers them flows into the veins in order to circulate back to the heart where pulmonary circulation will allow the exchange of gases in the lungs. During systemic circulation, blood passes through the kidneys. This phase of systemic circulation is known as renal circulation. During this phase, the kidneys filter much of the waste from the blood. Blood also passes through the small intestine during systemic circulation. This phase is called portal circulation. During this phase, the blood from the small intestine collects in the portal vein which passes through the liver.

Question 2: Which are the main parts of the circulatory system?

Answer: The circulatory system includes the heart, lungs, arteries, arterioles (small arteries), and capillaries, the blood vessels that carry oxygen-rich blood away from the heart. It also includes venules (small veins) and veins, the blood vessels through which blood flows as it returns to the heart and which carry oxygen-poor blood. If all the vessels of this network in human’s body were laid end-to-end, they would extend for about 60,000 miles!

Tubular circulation Located throughout human’s body, blood vessels are hollow tubes that circulate the blood. There are three varieties of blood vessels: arteries, veins, and capillaries.

During blood circulation, the arteries carry blood away from the heart. The capillaries connect arteries to veins, and finally the veins return the blood back to the heart.

Besides circulating blood, the blood vessels provide two important means of measuring vital health statistics: pulse and blood pressure. Heart rate or pulse is measured by touching an artery. The rhythmic contraction of the artery keeps pace with the beat of the heart. To measure blood pressure, we use the blood flowing through the arteries because it has a higher pressure than the blood in the veins. The blood pressure is measured using two numbers. The first one, which is higher, is taken when the heart beats during the systole phase. The second number is taken when the heart relaxes during the diastole phase. Normal blood pressure ranges from 110 to 150 millimeters (as the heart beats) over 60 to 80 millimeters (as the heart relaxes). It is normal for the blood pressure to increase when people are exercising and to decrease when they are sleeping.

Arteries

Arteries are tubes that carry blood away from the heart. The heart pumps blood out through one main artery called the dorsal aorta. The main artery then divides and branches out into smaller arteries so that each region of the body has its own system of arteries supplying it with fresh, oxygen-rich blood. An artery has three layers: an outer layer of tissue, a muscular middle, and an inner

layer of epithelial cells. The inside layer is very smooth, allowing the blood to flow quickly and easily without any obstacles in its path. The muscle in the middle is elastic and very strong. Finally, the outside layer is very strong, allowing the blood to flow forcefully. The muscular wall of the artery helps the heart pump the blood. When the heart relaxes, the artery contracts, exerting a force in order to push the blood along. Then, arteries deliver the oxygen-rich blood to the capillaries.

Capillaries Capillaries connect arteries and veins. They are thin and fragile. Capillaries are actually one epithelial cell thick, and blood cells can only pass through them in one single file.

The exchange of oxygen and carbon dioxide takes place through the thin capillary wall. The red blood cells inside the capillary release their oxygen which passes through the wall and into the surrounding tissue. The tissue releases its waste products, like carbon dioxide, which passes through the wall and into the red

blood cells. Capillaries are also involved in the body’s release of excess heat. Blood delivers the heat to the capillaries which then rapidly release it to the tissue. The result is that the skin takes on a flushed, red appearance.

Veins

Veins are tubes that return blood to the heart. They are not as strong as the arteries because they transport blood at a lower pressure. They consist of three layers: an outer of tissue, muscle in the middle, and a smooth inner layer of epithelial cells. The layers are thinner than those of arteries, containing less tissue. Veins receive blood from the capillaries and also 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 against the force of gravity (e.g. the blood from the foot), and not be allowed to flow backward. This is accomplished by one-way valves that are located inside the veins. Because it lacks oxygen, the waste-rich blood that flows through the veins has a deep purplish color.

Heart

The heart is a muscular organ located between the lungs in the middle of the chest, behind and

slightly to the left of the breastbone (sternum). It is about the size of human’s fist and it pumps 4300 gallons of blood a day. A double-layered membrane called the pericardium surrounds the heart like a sac. The outer layer of the pericardium surrounds the root of the heart’s major blood vessels and is attached by ligaments to the spinal column, diaphragm, and other parts of the body. The inner layer of it is attached to the heart muscle. A coating of fluid separates the two layers of membrane, letting the heart move as it beats, yet still be attached to your body. The heart weighs between 200 to 425 grams. It has four chambers. The upper chambers are called the left and right atria, they receive blood from the body or lungs. The lower chambers are called the left and right ventricles, they pumps blood to the rest of the body. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. The left ventricle is the largest and the strongest chamber in the heart.

A valve connects each atrium to the ventricle below it. The mitral valve connects the left atrium with the left ventricle. The tricuspid valve connects the right atrium with the right ventricle. There are also another two valves: the pulmonary valve and the aortic valve. The top of the heart connects to a few large blood vessels. Two of them are arteries- the aorta and the pulmonary artery- and the other two are veins- the superior and the inferior vena cava.

The heart’s structure make’s it an efficient, never-ceasing pump. The average cardiac muscle contracts and relaxes about 70 to 80 times per minute. Nerves connected to the heart regulate the speed with which the muscle contracts.

Blood

The blood is the transport system by which oxygen and nutrients reach the body’s cells, and waste materials, by those cells, are carried away. In addition, blood carries substances called hormones, which control body processes, and antibodies to fight invading germs.

Question 3: How does the heart work?

Answer: The role of the heart is to deliver the oxygen-rich blood to every cell in the body. As the cardiac muscle contracts it pushes blood through the chambers into the vessels. Blood flows continuously through the circulatory system, and the heart muscle is the pump which makes it all possible.

How does the heart pump blood?

Heart does it by a sequence of highly organized contractions of its four chambers. As blood collects in the upper chambers, the heart’s natural pacemaker sends out an electric signal that causes the atria to contract. This contraction pushes blood through the tricuspid and the mitral valves into the resting lower chambers. This part of the two-part pumping phase (the longer of two) is called the diastole. The second part of it begins when the ventricles are full of blood, then the mitral and tricuspid valves are closed. The electrical signals from the SA node cause the ventricles to contract. This is called systole.

As the tricuspid and mitral valves shut tight to prevent a back flow of blood, the pulmonary and aortic valves are pushed open and the blood is supplied to the lungs and the other parts of the body. Continuing, the ventricles relax, and the pulmonary and aortic valves close. The lower pressure in the ventricles causes the tricuspid and mitral valves to open, and the cycle begins again. This series of contractions is repeated over and over again, and it is affected by different factors. The human heart is a muscle designed to remain strong and reliable for a hundred of years or longer.

The conduction system

The heart also has an electrical system which includes a permanent pacemaker to regulate the heartbeat rate and specialized wiring to transmit the pacemaker beat to all parts of the heart, and cause the heart to beat (contract). The pacemaker (sinoatrial node) is located at the top of the right atrium. This pacemaker creates a miniature electrical impulse. The signal then passes through the atrioventricular (AV) node, which creates a short delay in the impulse

to allow the atria to contract and forces blood into the ventricles before they contract.

The AV node checks the signal and sends it through the muscle fibers of the ventricles, causing them to contract. The SA node sends electrical impulses at a certain rate, but your heart rate may still change depending on physical demands, stress, or hormonal factors.

Question 4: Draw and label the major parts of the heart.Answer:

Student 2: Koulina Anastasia

BLOOD

Question 1: What blood is made up and why is so important?

Answer: Blood is a liquid tissue. It moves in blood vessels and is circulated by the heart, a muscular pump. It passes to the lungs to be oxygenated and then is circulated throughout the body by the arteries. It diffuses its oxygen by passing through the capillaries. It then returns to the heart through the veins.

Blood is vital for life; without it the body would stop working. Its functions are: to transport

Oxygen from the lungs to body tissue and carbon dioxide from body tissue to the lungs

Nourishment from digestion throughout the body Hormones from glands throughout the body Disease fighting substances to the tissue Waste to the kidneys

Blood is composed of living cells (erythrocytes, leukocytes, thrombocytes constitute about 45% of whole blood) and plasma (the other 55%).

Erythrocytes (red blood cells)

They contain a protein called hemoglobin by which they deliver oxygen to body tissues and carry carbon dioxide back from the tissues. Human erythrocytes have a flattened ovate shape, depressed in the centre and lack a nucleus and organelles. They are flexible so as to fit through tiny capillaries. Their diameter is about 6-8 m. Adult humans have approximately 4-6 million erythrocytes per cubic millimeter of blood (women 4-5,

men 5-6). Erythrocytes are produced in the red bone marrow, develop in about 7 days and live about 120 days.

Leukocytes (white blood cells)

Leukocytes help to defend body against infectious disease and foreign materials as part of the immune system. There are normally between 4,000-10,000/μl of them at any time. There are many types of white cells:

Granulocytes

Neutrophile: (50-70% of whole leukocytes) they are the primary cells of acute inflammatory response and act by phagocytosing foreign materials and pathogens.

Eosinophile: (1-2%) they have a role in the allergic response and in defending parasites.

Basophile: (0-1%) their purpose is not clear.

Other White Cells

Lymphocytes: (20-40%) there are three types of lymphocytes, B cells (they make antibodies that bind to pathogens and destruct them), T cells (they co-operate

the immune system) and natural killer cells (they kill cells of the body that are infected by virus).

. Monocytes: (3-6%) they phagocytose pathogens

Thrombocytes (platelets)

Platelets are cells that stick together to form blood clots. They are irregularly-shaped, colorless broken-off pieces of megacaryocyte cytoplasm released from the red bone marrow into the blood stream. When there is a disturbance in the blood vessels (such as a broken vessel) they stick together at that point and prevent blood from coming out of the vessel. A normal platelet count in a healthy person is between 150,000 and 300,000/μl.

Blood plasma

Plasma is mainly composed of water (90%), proteins and mineral salts (calcium, sodium, magnesium and potassium). It serves as a transport medium for the blood cells, glucose, lipids, hormones, products of metabolism, carbon dioxide, oxygen and microbe-fighting antibodies.

Question 2: Conditions (3) associated with the heart and treatments/research.

Answer:

Hypertension

It is the medical term for high blood pressure. According to new guidelines released by the National Heart, Lung, and Blood Institute (NHGBI) in 2003, people with a blood pressure above 140/90 mm Hg are classified within the category “hypertension”

Category Systolic (mm Hg) Diastolic (mm Hg)Normal Lower than 120 Lower than 80Prehypertension 120-139 80-89HypertensionStage 1 140-159 90-99Stage 2 160 or higher 100 or higher High blood pressure results from the hardening of very small arteries, arterioles, which regulate the blood flow through the body. It can affect the health in four main ways:

Hardening the arteries. Their walls thicken and they become narrower. Enlarged heart. The amount of heart’s work is increased, causing the

heart grow bigger. The bigger the heart is, the less able is to maintain proper blood flow.

Kidney damage. Eye damage.

About 90-95% of all cases, the real cause is not known (primary or essential hypertension), although there is a number of risk factors associated (family history, male, older than 60, African Americans, stress, smoking, overweight, diet high in salt or saturated fat, alcohol, physical inactive, diabetes). The rest patients have secondary hypertension, which is a result of other conditions (kidney disorders, acromegaly, pregnancy, problems with the parathyroid gland, reactions to medicines).Symptoms: The patients usually have no symptoms, or some of them may have a pounding feeling in their chest or head, a feeling of lightheadedness or dizziness.Diagnosis: It is diagnosed by a doctor during a medical check-up.Treatment: The treatment involves lifestyle changes and, if it is necessary, administration of medicines (diuretics, ACE inhibitors, beta blockers, calcium channel blockers, vasodilators) which control the blood pressure.

Congestive Heart Failure (CHF)

Congestive Heart Failure is a condition in which the heart can not pump enough blood to meet the needs of the body’s other organs. It usually develops slowly; a patient may go for years without symptoms, and the symptoms become worse with time. This slow onset and progression of CHF is caused by the heart’s own efforts to deal with its graduate weakening. The heart tries to make up for this weakening by enlarging and by forcing itself to pump faster to move more blood through the body.Previous heart attacks, coronary artery disease, hypertension, irregular heartbeat, heart valve disease (especially of the aortic and mitral valves) cardiomyopathy, congenital heart defects are considered as risk factors for CHF.Symptoms: If the left side of the heart is not working properly, then blood and fluid back up to the lungs and the patient feels short of breath, very tired and has a cough.If the right side of the heart is not working properly, fluid is built up in the veins. The feet, legs and ankles swell (edema). Sometimes edema is spread to the lungs, liver and stomach. The patient may need to go to the bathroom more often, especially at night.Other symptoms are chest pain, irregular or fast pulse, cold and sweaty skin.Diagnosis: It is usually diagnosed by the presence of edema and shortness of breath. The imaging techniques used are chest X-ray, electrocardiography, echocardiography, nuclear ventriculography and angiography.Treatment: It includes lifestyle changes, medicines (diuretics, digitalis, vasodilators, beta blockers, ACE inhibitors, etc), transcatheter interventions (angioplasty, stenting) and surgical procedures (pacemaker insertion, coronary artery bypass surgery, heart valve repair or replacement, correction of congenital heart defects, mechanical assist devices, heart transplantation).

Stroke

Stroke is a form of a cerebrovascular disease, meaning it affects the vessels that supply blood to the brain. A stroke is caused when blood flow to the brain is blocked, either by a blood clot or by a weaken artery that bursts in the brain.

A blood clot or a blocked artery leading to the brain causes about 80% of all strokes (ischemic stroke).Oxygen supply is cut off and brain cells begin to die. The longer the brain is without blood, the more severe the damage will be.

The other 20% of strokes are caused by ruptured or leaky blood vessels in or around the brain (hemorrhagic stroke). Hemorrhagic strokes cause more deaths than ischemic ones, but patients who survive a hemorrhagic stroke recover more fully and have fewer long-lasting disabilities.

Effects: In people who survive stroke, there may be paralysis, emotional problems, or trouble with speech, memory or judgment. If the right side of the brain is affected, the left side of the body may become paralyzed. The effects may be severe or mild, short-term or permanent.

Diagnosis: Tests that show images of the brain (CT scan, MRI), measure the brain’s electrical activity (electroencephalography) and show the blood flow to the brain (carotid duplex scan) are used to find out the type and severity of stroke.Treatment: Treatment includes anti-clotting drugs, hospital care, hospital care, rehabilitation and, rarely, surgery.

Question 3: How can we maintain a healthy circulatory system?

Answer: In order to keep a healthy circulatory system, people should:

Get plenty of exercise Follow a good diet and manage their weight Control risk factors

Physical activity

Daily physical activity reduces the risk of heart disease and keeps weight under control. Other benefits are that it improves blood cholesterol levels, prevents and manages high blood pressure.A successful exercise program involves exercises that are rhythmic, repetitive, challenge the circulatory system and use large muscles (aerobic exercises). It must increase the blood flow to the

muscles for an extend period of time. Some aerobic exercises are walking, hiking, jogging, bicycling, swimming, jumping rope and roller skating. (http://www.nvo.com/upandmoving/benefits)

Diet

In order to maintain a healthy cardiovascular system and reduce the risk for heart diseases, people should follow a balanced diet. A balanced diet excludes foods that are rich in fat, especially saturated fat. These foods add many useless calories (obesity contributes to heart diseases) and can raise the level of cholesterol in the blood –which can lead to risk for heart diseases.

On the contrary, a suitable diet includes:

6-11 servings from the Bread, Cereal, Rice and Pasta Group at least 3-5 servings from the Vegetable Group 2-4 servings from the Fruit Group 2-3 items from Milk, Yoghurt and Cheese 2-3 servings from the Meat, Poultry, Fish, Dry Beans, Eggs and Nuts small quantities from Fats, Oils and Sweets

(http://www.apronstringsbabythings.com/make_your_own_baby_food.htm)

Risk factors

Smoking, alcohol and drug abuse, and stress are the main risk factors. Stress is the body’s response to change. Great range of stress can lead to habits like smoking, drinking, overeating or drug abuse. Even if someone does not feel stress at all, the body suffers from it.Smoking, taking drugs or drinking alcohol excessively give heart extra work, which the heart is not able to handle for a

long period of time. Smokers have double risk of having a heart attack, even quadruple risk of sudden cardiac death and high risk of developing chronic disorders, such as atherosclerosis. Additionally, the ratio of high-density lipoprotein (or good) cholesterol to low-density lipoprotein (or bad) cholesterol is lower in smokers than in nonsmokers. Former smokers can completely lower their risk of sudden cardiac death within ten years of quitting.Drinking alcohol in large quantities poses a serious hazard to the heart, because the blood cannot nourish the heart properly. The moderate intake of alcohol is an average of one or two drinks per day for men and one drink per day for women.(http://www.mankao.msus.edu/healthsv)

List of academic wordsTERM Example in Word class Dictionary Greek

context information definition translationMajor The major

factor that affects heart’s function is…

Adjective Very large or important ’serious

Μεγαλύτερος, κύριος

Affect The blood oxygen affects heart’s pulse.

Verb To have an influence on sb/sth

Επηρεάζω

Phase This phase of systemic circulation….

Noun a stage in a process of change or development

Φάση

Medium The medium layer of arteries is consisted of muscular fibers.

Adjective In the middle between two sizes, amounts, lengths, etc.

Μέτριος, μεσαίος

Layer An artery has three layers: an outer layer of tissue

Noun A level or part within a system

Στιβάδα, στρώμα

Treatment …he is receiving treatment for sock

Noun Something that is done to cure an illness or injury, or to make sb feel good

Θεραπευτική αγωγή

Techniques …teachers learn various techniques for dealing with problem students.

Noun A particular way of doing sth, especially one in which you have to learn special skills

Τεχνικές

Abuse ...what she did was an abuse of her position as a manager.

Noun The use of sth in a way that is wrong or harmful

Κατάχρηση

Challenge …he is looking

Noun A new or difficult task

Προκαλώ

forward to the challenge of his new job

that tests sb’s ability and skill

Obesity …obesity can increase the risk of heart disease.

Noun The condition of being very fat, in a way that is not healthy

Παχυσαρκία

List of medical wordsTERM Example in

contextWord class information

Dictionary Definition

Greek translation

Tissue …pushes blood to the organs, tissues, and cells of the body.

Noun Collection of cells organized in a cooperative arrangement for the purpose of performing a particular function

Ιστός

Renal (circulation)

This phase of systemic circulation is known as systemic circulation.

Adjective Something that ha to do with the kidney

Νεφρικός

Aorta The aorta branches off two...

Noun The main trunk of the systemic arteries.

Αορτή

Pulse ..measuring vital health statistics: pulse and blood pressure.

Noun The rhythmical expansion and contraction of an artery produced by waves of pressure caused by the ejection of blood from the left ventricle of the heart as it contracts.

Σφυγμός, παλμός

Intestine Blood also passes

Noun The section of the alimentary

Έντερο

through the small intestine during systemic circulation.

canal from the stomach to the anus. It includes the small intestine and the large intestine.

Diuretics …diuretics help rid your body of water and sodium

Noun A substance or drug that tends to increase the discharge of urine

Διουρητικά

Hormones ...oestrogen is a female sex hormone

Noun A chemical substance produced in the body that encourages growth or influences how the cells and tissues function

Ορμόνες

Angioplasty …angioplasty is used to open arteries narrowed by fatty plaque buildup

noun The surgical repair of a blood vessel

Αγγειοπλαστική

Atherosclerosis …a diet rich in saturated fats may cause atherosclerosis

noun A type of arteriosclerosis characterized by the deposition of plaques containing lipids and cholesterol on the inner layer of the walls of arteries

αθηροσκλήρωση

Edema …ankles begin to swell if fluid is built up in the veins; this swelling is

Noun An excessive accumulation of serous fluid in tissue spaces or a

Οίδημα

called edema body cavity

Websites consulted:http://en.wikipedia.org/wiki/http://sln.fi.edu/biosci/http://texasheartinstitute.org/http://www.rcpg.com/ http://www.tmc.edu/thi/http://www.americanheart.org/presenter.jtml?identifier=4598http://www.accessexcellence.org/AE/AEC/CC/heart_graphics/ Human_Heart.gifhttp://www.accessexcellence.org/AE/AEC/CC/heart_graphics/ Open_Heart.gifhttp://www.jhbmc.jhu.edu/cardiology/rehab/healthy.heart.html