Organ weight is a complex subject. There are many factors — including body weight, height, lean body mass, and race — that cause organ weights to vary widely. Furthermore, this data needs to come from different types of people. Right now, such data are not routinely collected. Organ weights used for reference need to come from forensic autopsieswhich are usually performed in cases of suspicious, sudden, or traumatic death where a dead person's organs are otherwise healthy.
Furthermore, the number of autopsies performed is plummeting, giving researchers fewer opportunities to access and assess organ weights. Despite being poorly appreciated and minimally researched, organ weights and size are still used by health care professionals to determine the cause of death and disease as well as to guide certain treatments. InFrench researcher Grandmaison and co-authors published a paper in Forensic Science International analyzing organ weights from autopsies performed on whites between and Based on the results of this study, the following are mean organ weights and ranges for men and women:.
To some extent, these values lack generalizability and can't automatically be applied to all people in a population. Even though humans change very slowly over time, the results of this study are already dated. However, the sample size of this study is small and the results are somewhat dated.
According to the formula, a woman who carries 40 pounds of total body fat would have breasts that weight about 1. Furthermore, histological changes in the composition of the breasts can sometimes affect breast weight. It has to do with the density of the tissue —and fat is very low density. In one person, that tumor may represent a third of her breast mass, and in another person, that tumor may represent less than one percent of her breast mass.
Besides disease, another important factor that affects breast mass is diet and exercise. When people lose weight, they tend to do so uniformly. For example, if a pear-shaped woman were to lose weight, she would still retain her pear shape but at a smaller mass. She would be proportionately smaller. A woman who loses weight will not experience a conspicuous decrease in breast size.
Her breasts would be appropriate for her new weight and in proportion with the rest of her body— everything would just be smaller. On a related note, as with the breasts, people lose a proportional amount of weight from the buttocks while dieting. Research shows that people who are taller, weigh more have a higher body mass index, or BMIand have more lean body mass may have heavier organs. Of these factors, some research suggests that height may best correlate with most organ weights; taller people have organs that weigh more and are proportionately bigger.
Interestingly, female thyroid weight has little to do with height, weight, and lean body mass. Instead, female thyroid weight may be most influenced by iodine intake. In areas where the vast majority of women consume enough iodine in their diets, thyroid weights typically fall within a uniform range for all women.
Age and sex also affect organ weight. On average, women tend to have lighter organs than men do.The heart is a muscular organ in most animals, which pumps blood through the blood vessels of the circulatory system. In humans, other mammals, and birds, the heart is divided into four chambers: upper left and right atria and lower left and right ventricles.
The wall of the heart is made up of three layers: epicardiummyocardiumand endocardium. The heart pumps blood with a rhythm determined by a group of pacemaking cells in the sinoatrial node. These generate a current that causes contraction of the heart, traveling through the atrioventricular node and along the conduction system of the heart.
The heart receives blood low in oxygen from the systemic circulationwhich enters the right atrium from the superior and inferior venae cavae and passes to the right ventricle. From here it is pumped into the pulmonary circulationthrough the lungs where it receives oxygen and gives off carbon dioxide. Diagnosis of heart disease is often done by the taking of a medical historylistening to the heart-sounds with a stethoscopeECGand ultrasound.
The human heart is situated in the middle mediastinumat the level of thoracic vertebrae T5-T8. A double-membraned sac called the pericardium surrounds the heart and attaches to the mediastinum. The upper part of the heart is located at the level of the third costal cartilage.
The largest part of the heart is usually slightly offset to the left side of the chest though occasionally it may be offset to the right and is felt to be on the left because the left heart is stronger and larger, since it pumps to all body parts. Because the heart is between the lungsthe left lung is smaller than the right lung and has a cardiac notch in its border to accommodate the heart.
The heart has four chambers, two upper atriathe receiving chambers, and two lower ventriclesthe discharging chambers.
What Is the Weight of the Human Heart?
The atria open into the ventricles via the atrioventricular valves, present in the atrioventricular septum. This distinction is visible also on the surface of the heart as the coronary sulcus. Similarly, the left atrium and the left ventricle together are sometimes referred to as the left heart.
The cardiac skeleton is made of dense connective tissue and this gives structure to the heart. It forms the atrioventricular septum which separates the atria from the ventricles, and the fibrous rings which serve as bases for the four heart valves. The interatrial septum separates the atria and the interventricular septum separates the ventricles. The heart has four valves, which separate its chambers. One valve lies between each atrium and ventricle, and one valve rests at the exit of each ventricle.
The valves between the atria and ventricles are called the atrioventricular valves. Between the right atrium and the right ventricle is the tricuspid valve.
The tricuspid valve has three cusps,  which connect to chordae tendinae and three papillary muscles named the anterior, posterior, and septal muscles, after their relative positions.
It is also known as the bicuspid valve due to its having two cusps, an anterior and a posterior cusp. These cusps are also attached via chordae tendinae to two papillary muscles projecting from the ventricular wall. The papillary muscles extend from the walls of the heart to valves by cartilaginous connections called chordae tendinae. These muscles prevent the valves from falling too far back when they close.
As the heart chambers contract, so do the papillary muscles. This creates tension on the chordae tendineae, helping to hold the cusps of the atrioventricular valves in place and preventing them from being blown back into the atria. Two additional semilunar valves sit at the exit of each of the ventricles. The pulmonary valve is located at the base of the pulmonary artery. This has three cusps which are not attached to any papillary muscles. When the ventricle relaxes blood flows back into the ventricle from the artery and this flow of blood fills the pocket-like valve, pressing against the cusps which close to seal the valve.
The semilunar aortic valve is at the base of the aorta and also is not attached to papillary muscles. This too has three cusps which close with the pressure of the blood flowing back from the aorta. The right heart consists of two chambers, the right atrium and the right ventricle, separated by a valve, the tricuspid valve.
The right atrium receives blood almost continuously from the body's two major veins, the superior and inferior venae cavae.Electronic address: n. The impact of cancer is less studied, and the influence of age is not unequivocal. We aimed to describe the relationship between body size and heart weight in a large autopsy cohort and to compare heart weight in patients with cancer, CVD, and other diseases. In this last group, heart weight correlated only slightly better with body surface area than body weight, and nomograms based on body weight are presented.
Similar results were obtained in linear regression models adjusted for body weight and age. Among CVD, heart valve disease had the greatest impact on heart weight, followed by old myocardial infarction, coronary atherosclerosis, and hypertension. Absolute heart weight decreased with age, but we demonstrated an increase relative to body weight.
While the most prevalent types of CVD are associated with increased heart weight, patients who die from cancer have lower average heart weight than other patient groups.
The latter finding, however, is diminished when adjusting for body weight. SUMMARY: The present study demonstrates that the weight of the human heart is influenced by various disease processes like cancer and CVD, in addition to body weight, gender and, possibly, age.The heart is a hollow, cone-shaped muscle located between the lungs and behind the sternum breastbone.
The apex pointed end points down and to the left.
How Much Does the Human Heart Weigh?
It is 5 inches 12 cm long, 3. The average weight of a female human heart is 9 ounces and a male's heart is The heart comprises less than 0. The heart has three layers. The smooth, inside lining of the heart is called the endocardium. The middle layer of heart muscle is called the myocardium. It is surrounded by a fluid filled sac call the pericardium. When someone listens to your heart with a stethoscope the sound is often described as lub-dub lub-dub.
The first heart sound lub is caused by the acceleration and deceleration of blood and a vibration of the heart at the time of the closure of the tricuspid and mitral valves.
The second heart sound dub is caused by the same acceleration and deceleration of blood and vibrations at the time of closure of the pulmonic and aortic valves. What makes your heart beat? How and why does the heart pump blood to itself? Prev NEXT. The Human Heart. That's why the left and right labels here seem backwards.A physician once placed dying patients upon a scale and determined the weight of the human soul to be 21 grams.
A doctor in the early 20th century weighed several patients at the moment of death in order to determine the weight of their departing souls.
These experiments were extremely flawed and demonstrated nothing credible about the human soul or post-mortem weight loss. Most of those of a religious bent believe in life everlasting for the faithful, a continuation of the life force that reaches far beyond the limitations of mortal flesh.
In such belief systems, death is not an end but a transformation: though people shed their corporeal selves at the moment of demise, that which made them unique beings lives on to rejoin the Creator.
Without the soul, dead is dead. But if it could be proved to exist, a great deal of anxiety over what happens to us when we die would be vanquished. Those who believe that the body becomes lighter [at the moment of death] seem to think that the soul has weight, weight that must of necessity depart with it, and — with that brisk disregard of strict veracity which so frequenly marks discussions of this nature — have claimed that dying men, at the very moment of their decease, have been placed on delicate scales that have recorded their mortuary degravitation.
The doctor postulated the soul was material and therefore had mass, ergo a measurable drop in the weight of the deceased would be noted at the moment this essence parted ways with the physical remains. The belief that human beings are possessed of souls which depart their bodies after death and that these souls have detectable physical presences were around well before the 20th century, but claims that souls have measurable mass which falls within a specific range of weights can be traced to experiments conducted by Dr.
MacDougall in He installed upon this bed a succession of six patients in the end stages of terminal illnesses four from tuberculosis, one from diabetes, and one from unspecified causes ; observed them before, during, and after the process of death; and measured any corresponding changes in weight.
He then attempted to eliminate as many physiological explanations for the observed results as he could conceive:. He lost weight slowly at the rate of one ounce per hour due to evaporation of moisture in respiration and evaporation of sweat. During all three hours and forty minutes I kept the beam end slightly above balance near the upper limiting bar in order to make the test more decisive if it should come.
At the end of three hours and forty minutes he expired and suddenly coincident with death the beam end dropped with an audible stroke hitting against the lower limiting bar and remaining there with no rebound. The loss was ascertained to be three-fourths of an ounce. This loss of weight could not be due to evaporation of respiratory moisture and sweat, because that had already been determined to go on, in his case, at the rate of one sixtieth of an ounce per minute, whereas this loss was sudden and large, three-fourths of an ounce in a few seconds.
The bowels did not move; if they had moved the weight would still have remained upon the bed except for a slow loss by the evaporation of moisture depending, of course, upon the fluidity of the feces. The bladder evacuated one or two drams of urine.
This remained upon the bed and could only have influenced the weight by slow gradual evaporation and therefore in no way could account for the sudden loss.
There remained but one more channel of loss to explore, the expiration of all but the residual air in the lungs. Getting upon the bed myself, my colleague put the beam at actual balance. Inspiration and expiration of air as forcibly as possible by me had no effect upon the beam.
My colleague got upon the bed and I placed the beam at balance. Forcible inspiration and expiration of air on his part had no effect. In this case we certainly have an inexplicable loss of weight of three-fourths of an ounce. Is it the soul substance? How other shall we explain it? Fellow Massachusetts doctor Augustus P. Clarke took MacDougall to task for having failed to take into account the sudden rise in body temperature at death when the blood stops being air-cooled via its circulation through the lungs.The human heart is an organ that pumps blood throughout the body via the circulatory system, supplying oxygen and nutrients to the tissues and removing carbon dioxide and other wastes.
In humans, the heart is roughly the size of a large fist and weighs between about 10 to 12 ounces to grams in men and 8 to 10 ounces to grams in women, according to Henry Gray's " Anatomy of the Human Body. The physiology of the heart basically comes down to "structure, electricity and plumbing," Phillips told Live Science. The right atrium and right ventricle together make up the "right heart," and the left atrium and left ventricle make up the "left heart.
A double-walled sac called the pericardium encases the heart, which serves to protect the heart and anchor it inside the chest. Between the outer layer, the parietal pericardium, and the inner layer, the serous pericardium, runs pericardial fluid, which lubricates the heart during contractions and movements of the lungs and diaphragm. The heart's outer wall consists of three layers. The outermost wall layer, or epicardium, is the inner wall of the pericardium.
The middle layer, or myocardium, contains the muscle that contracts. The inner layer, or endocardium, is the lining that contacts the blood. The tricuspid valve and the mitral valve make up the atrioventricular AV valves, which connect the atria and the ventricles. The pulmonary semi-lunar valve separates the right ventricle from the pulmonary artery, and the aortic valve separates the left ventricle from the aorta.
The heartstrings, or chordae tendinae, anchor the valves to heart muscles.
Human Heart: Anatomy, Function & Facts
In the pulmonary circuit, deoxygenated blood leaves the right ventricle of the heart via the pulmonary artery and travels to the lungs, then returns as oxygenated blood to the left atrium of the heart via the pulmonary vein. In the systemic circuit, oxygenated blood leaves the body via the left ventricle to the aorta, and from there enters the arteries and capillaries where it supplies the body's tissues with oxygen.
Deoxygenated blood returns via veins to the venae cavae, re-entering the heart's right atrium. Of course, the heart is also a muscle, so it needs a fresh supply of oxygen and nutrients, too, Phillips said. The left main coronary artery, on one side of the aorta, branches into the left anterior descending artery and the left circumflex artery.
The right coronary artery branches out on the right side of the aorta. A heart attack is distinct from cardiac arrest, which is a sudden loss of heart function that usually occurs as a result of electrical disturbances of the heart rhythm. A heart attack can lead to cardiac arrest, but the latter can also be caused by other problems, he said. The heart contains electrical "pacemaker" cells, which cause it to contract — producing a heartbeat.
In people with an irregular heartbeat, or atrial fibrillation, every cell tries to be the band leader, he said, which causes them to beat out of sync with one another. A healthy heart contraction happens in five stages. In the first stage early diastolethe heart is relaxed.
Then the atrium contracts atrial systole to push blood into the ventricle. Next, the ventricles start contracting without changing volume. Then the ventricles continue contracting while empty.I n one of his essays, John Berger recalls having been taught at art school by a painter named Bernard Meninsky, who smelled of dill pickles. It should be admitted at the outset that the rather rich and fruity fragrance of The Weight of a Human Heart will not be to everyone's taste — too sickly, too sweet, and too overpowering.Human Circulatory System
Here's swank: a story told entirely through diagrams and graphs; a story told through EFL textbook exercises; a story told through its footnotes; a story told using the writing tips of great writers. Self-regarding, self-conscious, self-aware, these are stories that will dazzle and impress, or appal. What's amazing is not the prose, but the audacity of the ideas — audacious as in cocky, rather than cutting-edge.
This is not concept art, but the literature of conceit: gimmick follows gambit follows gizmo, as surely as the theme from Raiders of the Lost Ark follows ET and Star Wars in a medley from the movies.
Most of the stories announce their content with bright neon-lit titles: "Four Letter Words" is a story about four letter words; "Seventeen Rules for Writing a Short Story" proposes 17 rules for writing a short story; "Tyypographyy" plays with typography. According to O'Neill's acknowledgments, several of the stories were written as part of a PhD in creative writing, and the book might usefully be consulted — or indeed subtitled — as A Classic Compendium of Creative Writing Tricks and Devices.
We get Self-Referential Openings: "This story is 1, words long. Most of it is written in the past tense and in the first person. It's a true story, but the direct speech is approximate. I've read too many books where the writer claims to remember every word from a conversation which took place seventy years before" "A Short Story" ; "This story is set in Muloobinba, a fictional analogue of Newcastle, New South Wales" "A Story in Writing".
We get Spellbinding Conclusions: "'Shazam,' I whisper. And we get Unexpectedly Moving Passages and Moments of Tenderness and Heartbreak, most notably in a number of stories set in or about Rwanda, in particular "The Cockroach", perhaps the finest story in the collection. This is unadorned and unplugged, and ends with the unnamed protagonist, a young girl, standing at a river's edge, on the run.
She could feel the hands of the dead holding her afloat as she swam through the darkness. At its worst, the book suffers from the kind of scholasticism that produces stories according to a formula. But at its best, the book is possessed of an admirable logic and clarity. Scrupulosity provides opportunities as well as imposing limits.
The mother is called Margaret Hately: the story is simply delightful. The Weight of a Human Heart has all the urgency and vigour, then, that one might expect from a first collection: daring, intelligent, witty, full of new discoveries and exhilarations.
Topics Fiction. Short stories reviews. Reuse this content. Order by newest oldest recommendations.