Main Organs of Human Body
Introduction:
Organs are collection of tissues that perform specific functions in the human body. Different organs have different functions according to their structure. Many internal organs in the human body. The main organs of human body are these
Ø Brain
Ø Heart
Ø Stomach
Ø Kidney
Ø Liver
Ø Lungs
Brain:
The brain serves as the center of the nervous system in all vertebrates and most invertebrates. It is the most sophisticated organ in the human body. It is the control center of human body. It is covered with a hard bone called the skull. It is a component of the central nervous system (CNS).
Size and Weight of the Brain:
The human brain is about the size of a ball. Average weight of the human brain is about three pounds. It is approximately 2% of weight of the human body.
Composition of the Brain:
The brain is a large mass of nerves. It is about 60% fats and 40% is a combination of protein, water, carbohydrates, and salts. It has neurons and glial cell. It also contains blood vessels.
Functions of the Brain:
· Control our body temperature.
· Controls reproductive functions.
· Control our thoughts and emotions.
· Control hunger.
· Control breathing.
· Control vision.
· Control motor skills.
Heart
The heart is a muscular organ. It is located between the lungs in the thoracic cavity slightly left of the breast bone. It has four chambers. It is the primary organ of the circulatory system of human body. It has four compartments, two ventricles and two artria.
Size and Weight of the Heart:
The heart is about the size of large fist, and the average weight of a human heart is 280–340g in males and 230–280g in females.
Composition of the Heart:
The heart is composed of three layers e.g., endocardium, myocardium, and epicardium. Epicardium is the outer layer of the heart which make the surface of the heart. Myocardium is the middle layer and thickest layer of the heart. Endocardium is a thin layer which lines interior of the heart.
Functions of the Heart:
· The main function of the heart is to pump blood throughout the body.
· Blood carries oxygen, glucose hormones, and other components to different parts of the body.
· It also maintains the blood pressure of the human body.
Stomach:
Stomach is the muscular organ that digest food. It is the part of digestive system. It is found in the upper abdomen on the left side of the body. The upper part of the stomach is attached with esophagus (food pipe) and the lower part is attached with our small intestine.
Size and Weight of Stomach:
The stomach is a J-shaped muscular bag. Its size and weight vary from person to person. It mostly depends on the amount of food which we have eaten recently.
Composition of Stomach:
The stomach consists of four layers of tissues: serosa, muscularisexterna, submucosa, and mucosa. The outer layer of the stomach wall is smooth. The inner layers are thrown into folds.
Functions of Stomach:
· It temporarily stores food.
· It mixes food by contracting and relaxing.
· It breaks the food particles.
· It produces different enzymes and specialized cells for the digestion of food.
Kidneys:
Kidneys are the main organs our excretory system. These are present just below our ribcage on each side of the spine. The right kidney is slightly lower than the left one to make space for the liver.
Size and Weight of Kidneys:
Kidneys are bean-shaped organs. Each kidney is 3cm thick, 6cm wide, and 12cm long. The average weight of a kidney is 129 g for the left and 129 g for the right one.
Composition of Kidneys:
Kidneys have concave and convex borders. On the convex, outer layer of the kidney, there is a tough capsule, and on the concave side, a notch is present, which is called the hilum. The internal side of the kidney is divided into an outer renal cortex and an inner renal medulla.
Functions of the Kidneys:
· The main function of the kidney is to form urine by filtering the blood.
· It secretes hormones like erythropoetin, renin, and calcitroil.
· It maintains water and salt levels in our body.
· It also controls the acid-base level in our body.
· It also maintains the level of minerals in our body.
Liver:
The Liver is a largest solid organ which is found on the right side of the abdominal cavity, behind the lower ribs. It is a reddish-brown organ. It is also the largest gland in our body. It is shaped like a half moon.
Size and Weight of the Liver:
The liver is about the size of a football. It weighs about three pounds for an average-sized person. It is mostly 15 cm wide but varies with age and some medical conditions.
Composition of the Liver:
The liver consists of four lobes: the larger right lobe and left lobe, and the smaller lobes. Lobes are divided into eight segments, which are further divided into thousands of lobules.
Functions of the Liver:
· The main function of liver is bile production, which helps in breakdown of fats in the small intestine.
· It produces certain proteins for blood plasma.
· It produces cholesterol which, carries fats from the body.
· It converts excess glucose into glycogen.
· It also controls the level of amino acids, which are building blocks of protein.
· It removes drugs and other poisonous substances from the blood.
Lungs:
Lungs are the major organs of our respiratory system. These are pinkish-spongy organs. These are present in our chest, covered with our ribs. These are attached to the trachea (wind pipe).
Size and Weight of Lungs:
Lungs are in triangular shape. If we look at both lungs together, they look like elephant ears. In a normal human, the weight of lungs is approximately 1000g, which is normally 40% to 50% blood. These are 27 cm in height.
Composition of Lungs:
The lungs are divided into sections and lobes. The right lung has three lobes, and the left lung has two lobes. The left lung makes room for the heart, and it is slightly lower than the right lungs.
Functions of the Lungs:
· The major function of lungs is respiration (breathing).
· They exchange the gases with our circulatory system.
· They protect us from unwanted dust particles.
· They also regulate our blood volume.
Conclusion:
The main organs of the human body run our body. Without these organs, it is impossible for a human to survive. These organs complete the major systems of our body.
