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An essay on the circulatory system
An essay on the circulatory system
An essay on the circulatory system
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The heart
The heart is one of the most significant organs in the entire human body. It is really nothing more than a pump, collected of muscle which pushes blood throughout the body, beating roughly
72 times per minute of our lives. The heart pumps the blood, which transports all the vital materials which help our bodies function and eliminates the unwanted products that we do not need. For example, the brain needs oxygen and glucose, which, if not received endlessly, will cause it to loose awareness.
Muscles need oxygen, glucose and amino acids, as well as the precise percentage of sodium, calcium and potassium salts in order to contract routinely. The glands need adequate supplies of raw materials from which to manufacture the specific secretions. If the heart ever ceases to pump blood the body begins to shut down and after a very short period of time will expire.
The heart is fundamentally a muscle (a little larger than the fist).
Like any other muscle in the human body, it contracts and expands.
Unlike skeletal muscles, however, the heart works on the "All -or-
Nothing Law". That is, each time the heart contracts it does so with all its power. In skeletal muscles, the distinctive of "gradation" is present. The pumping of the heart is called the Cardiac Cycle, which occurs roughly 72 times per minute. This means that each cycle lasts around eight-tenths of a second. During this cycle the entire heart basically rests for about four-tenths of a second.
Makeup of the Heart
The walls of the heart are made up of three layers, while the cavity is separated into four parts. There are two upper chambers, called the right and left atria, and two lower chambers, called the right and left ventricles. The Right A...
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...ut by the regular age of 70 years, we see that the cardiac output of the normal human heart over a life time would be approximately 1 million litres, or about 250,000 gallons(US)!
Works Cited
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=1&cad=rja&ved=0CCkQFjAA&url=http%3A%2F%2Fwww.webmd.com%2Fheart-disease%2Fguide%2Fhow-heart-works&ei=34KBUpC5B-mKiAL9i4CQAQ&usg=AFQjCNH0xTJSyAkZk7vbV5cwezEx1hLzIw http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=6&cad=rja&ved=0CFEQFjAF&url=http%3A%2F%2Fkidshealth.org%2Fkid%2Fhtbw%2Fheart.html&ei=34KBUpC5B-mKiAL9i4CQAQ&usg=AFQjCNFMzFAlWpk6TLHyYak4Y_VHOK2XnA http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=2&cad=rja&sqi=2&ved=0CC0QFjAB&url=http%3A%2F%2Fscience.howstuffworks.com%2Flife%2Fhuman-biology%2Fheart.htm&ei=fIeBUqeWHMqliQK1xIFI&usg=AFQjCNGE3AHhdztxr-pLjajd_Fw4hoF8jQ
1.2 & 1.3 Explain The Cardiac Cycle And Describe How The Heart Rate Is Modified According To The Needs Of The Body
In this figure, SN = sinus node; AVN = AV node; RA = right atrium; LA
The blood circulates through coronary arteries and then to smaller vessels into cardiac muscle (myocardium). The blood flow is influenced by aortic pressure, which increases in systole, and the pumping activity of the ventricles. When the ventricle contracts, in systole, the coronary vessels are compressed by the contracted myocardium and partly blocked by the open aortic valve therefore the blood flow through the myocardium stops.
The heart is an extraordinary structure that is the base of all human life. However, it similar to the uncomplicated functions of water pumps. As the heart beats, blood is distributed throughout the body using a network of blood vessels. The functions of the heart can be kept in regular and healthy conditions through exercise. Exercise has an effect on the blood that is circulating through the body. That circulating blood makes the heart desire more oxygen, causing the heart rate to increase rapidly to keep up with activity demand.
The cardiovascular system - The cardiovascular system is responsible for transporting nutrients and removing gaseous waste from the body. It consists of the heart, which powers the whole process, the veins, arteries, and capillaries, which deliver oxygen to tissue at the cellular level. The cardiovascular system carries blood that is low in oxygen away from the heart to the lungs via arteries, where oxygen levels are restored through the air once oxygenated, this blood is then carried throughout the body via arteries, keeping our organs and tissue alive. The cardiovascular system is the workhorse of the body, continuously moving to push blood to the cells. If this important system ceases its work, the body dies.
The human body is an amazing machine, we have cells, tissues, organs and organ system that come together to create the human race. Each system plays a key role in our bodies mechanism. Without each systems our bodies would not function properly, but what happens when one of these system fails? The Cardiovascular system components are blood, blood vessels and the heart. The hearts function is to pump blood to all the major organs and tissues (Circulatory). It’s also important to be aware of the derivation that our bodies may encounter, for example a stroke. In this passage I discuss different types of strokes, what are the signs and symptoms and after care for this disorder of the cardiovascular system.
In the Tell-Tale Heart the story speak about a murder. The narrator telling the story
the heart is made of a muscle called the cardiac muscle unlike other muscles in the body the cardiac muscle never gets tiered its constantly working and never stops. It squeezes blood out of the heart and then relaxes it to fill it back with blood again in and this process continues and happens everyday until you are dead. The heart beats non stop this is achieved because of the cardiac Muscle.
The behavior of the narrator in The Tell-Tale heart demonstrate characteristic that are associated with people with obsessive-compulsive disorder and paranoid schizophrenia . When Poe wrote this story in 1843 obsessive-compulsive disorder and paranoia had not been discovered. However in modern times the characteristics demonstrated by the narrator leads people to believe that he has a mental illness. Poe’s narrator demonstrates classic signs throughout the story leading the reader to believe that this character is mad
State: The cardiac cycle is composed of five stages which each trigger the relaxation or contraction of the atria or ventricles and direction of blood flow. Elaborate: The cardiac cycle of the heart is divided into diastole and systole stages. Diastole refers to the period of relaxation experienced by the atria and ventricles. Systole is the contraction of the atria and ventricles.
The heart serves as a powerful function in the human body through two main jobs. It pumps oxygen-rich blood throughout the body and “blood vessels called coronary arteries that carry oxygenated blood straight into the heart muscle” (Katzenstein and Pinã, 2). There are four chambers and valves inside the heart that “help regulate the flow of blood as it travels through the heart’s chambers and out to the lungs and body” (Katzenstein Pinã, 2). Within the heart there is the upper chamber known as the atrium (atria) and the lower chamber known as the ventricles. “The atrium receive blood from the lu...
Just as breast cancer is killing our African American women, heart disease is also one of the major diseases killing our women. Heart disease is one of the nation’s leading causes of death in both woman and men. About 600,000 people die of heart disease in the United States (Americas heart disease burden, 2013). Some facts about heart disease are every year about 935,000 Americans have a heart attack. Of these, 610,000 are a first heart attack victim. 325,000 happen in people who have already had a heart attack. Also coronary heart disease alone costs the United States $108.9 billion each year. This total includes the cost of health care services, medications, and loss of productivity. Deaths of heart disease in the United States back in 2008 killed about 24.5% of African Americans.
The heart is two sided and has four chambers and is mostly made up of muscle. The heart’s muscles are different from other muscles in the body because the heart’s muscles cannot become tired, so the muscle is always expanding and contacting. The heart usually beats between 60 and 100 beats per minute. In the right side of the heart, there is low pressure and its job is to send red blood cells. Blood enters the right heart through a chamber which is called right atrium. The right atrium is another word for entry room. Since the atrium is located above the right ventricle, a mixture of gravity and a squeeze pushes tricuspid valve into the right ventricle. The tricuspid is made up of three things that allow blood to travel from top to bottom in the heart but closes to prevent the blood from backing up in the right atrium.
It is about the size of a person's fist. The heart has four chambers. The upper two chambers are the right artium and left atrium, and the lower two are the right ventricle and left ventricle. Blood is pumped through the chambers, aided by four heart valves. The valves open and close to let the blood flow in only one direction.
The heart is a pump with four chambers made of their own special muscle called cardiac muscle. Its interwoven muscle fibers enable the heart to contract or squeeze together automatically (Colombo 7). It’s about the same size of a fist and weighs some where around two hundred fifty to three hundred fifty grams (Marieb 432). The size of the heart depends on a person’s height and size. The heart wall is enclosed in three layers: superficial epicardium, middle epicardium, and deep epicardium. It is then enclosed in a double-walled sac called the Pericardium. The terms Systole and Diastole refer respectively and literally to the contraction and relaxation periods of heart activity (Marieb 432). While the doctor is taking a patient’s blood pressure, he listens for the contractions and relaxations of the heart. He also listens for them to make sure that they are going in a single rhythm, to make sure that there are no arrhythmias or complications. The heart muscle does not depend on the nervous system. If the nervous s...