Characteristic of the vertebrate form, the human body has an internal skeleton that includes a backbone of vertebrae. Digestive system – The digestive system includes the mouth, throat, stomach, liver, and intestines. The evolution of the human eyebrows is believed to have prevented the influx of sweat into the eyes. Cardiovascular system. Calcium is also present as ions in the blood and interstitial fluid, as is sodium. Their experiences with everyday cuts, scratches and bruises seem to reinforce a view that blood is below the surface of the skin, filling the spaces inside the body (like a bag of blood).Older children are more likely to be able to … Articles from Britannica Encyclopedias for elementary and high school students. Get exclusive access to content from our 1768 First Edition with your subscription. The liver and pancreas also play a role in the digestive system because they produce digestive juices. Our skin also helps regulate body temperature and eliminate waste through perspiration. Adults excrete about a quarter and a half (1.42 liters) of urine each day. Human body, the physical substance of the human organism, composed of living cells and extracellular materials and organized into tissues, organs, and systems. The Central Nervous System (CNS), consisting of the brain and spinal cord, is responsible for the processing of thought, cognition, and other such functions. These four basic cell types, together with their extracellular materials, form the fundamental tissues of the human body: (1) epithelial tissues, which cover the body’s surface and line the internal organs, body cavities, and passageways; (2) muscle tissues, which are capable of contraction and form the body’s musculature; (3) nerve tissues, which conduct electrical impulses and make up the nervous system; and (4) connective tissues, which are composed of widely spaced cells and large amounts of intercellular matrix and which bind together various body structures. For detailed coverage of the body’s biochemical constituents, see protein; carbohydrate; lipid; nucleic acid; vitamin; and hormone. All of these ions play vital roles in the body’s metabolic processes. Rachael Rettner - Senior Writer Internal organs and their functions Human Body depends on internal organs to perform … Body systems Our bodies consist of a number of biological systems that carry out specific functions necessary for everyday living. Live Science is part of Future US Inc, an international media group and leading digital publisher. Let us know if you have suggestions to improve this article (requires login). It is widely believed that there are 100 organs; however, there is no universally standard definition of what constitutes an organ, and some tissue groups' status as one is debated. Body Parts! This system allows the human brain to control various parts of the body through its large nerve network . Does insulin regulate the level of sugar in the body? The main organs that function in the urinary system are the kidneys and bladder. The bone marrow. The job of the circulatory system is to move blood, nutrients, oxygen, carbon dioxide, and hormones, around the body. The male reproductive system includes the penis and the testes, which produce sperm. Do humans have only five senses? The skeleton not only helps us move, but it's also involved in the production of blood cells and the storage of calcium. The human heart is a responsible for pumping blood throughout our body. The human nervous system can relay electrochemical messages at a rate of 249 mph (400 km/hr). The epithalamus serves as a connection between the limbic system and other parts of the brain. From the pharynx there are two paths that the food bolus can take; 1) the wrong path, which is down the windpipe into the lungs, or 2) the correct path into the esophagus and then the stomach.The act of swallowing is a complex process that closes the windpipe (to protect our lungs) and moves food into the esophagus. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. (Bone and blood are considered specialized connective tissues, in which the intercellular matrix is, respectively, hard and liquid.). Major Brain Parts and Regions: The human brain resembles, in both structure and function, with that of other vertebrates. The skin, or integumentary system, is the body's largest organ. It consists of the heart, blood, blood vessels,arteries and veins. They tend to think the contents of the body are what they have seen being put into or coming out of it, such as food and blood. The immune system is the body's defense against bacteria, viruses and other pathogens that may be harmful. Many entries describe the body’s major structures. The body includes nine major organ systems, each composed of various organs and tissues that work together as a functional unit. (5) The digestive system, composed of the mouth, esophagus, stomach, and intestines, breaks down food into usable substances (nutrients), which are then absorbed from the blood or lymph; this system also eliminates the unusable or excess portion of the food as fecal matter. Every physical action that a person consciously performs (e.g. Chemically, the human body consists mainly of water and of organic compounds—i.e., lipids, proteins, carbohydrates, and nucleic acids. Deoxyribonucleic acid (DNA) carries the body’s hereditary master code, the instructions according to which each cell operates. The basic parts of the human body are the head, neck, torso, arms and legs. Proteins also serve as a major structural component of the body. Lateral view of the human muscular system. THE HUMAN BODY SYSTEMS System Function Diagram Major Organs Interactions- Working with Other Systems Digestive 1. take in food (ingestion) 2. digest food into smaller molecules and absorb nutrients 3. remove undigestable food from body (feces) Mouth, esophagus, stomach, Sm. The kidneys take urea out of the blood and combine it with water and other substances to make urine. Like all chordates, the human animal has a bilaterally symmetrical body that is characterized at some point during its development by a dorsal supporting rod (the notochord), gill slits in the region of the pharynx, and a hollow dorsal nerve cord. Small amounts of carbohydrates also occur in cell membranes, but, in contrast to plants and many invertebrate animals, humans have little structural carbohydrate in their bodies. In fact, most body parts are far more complicated than that, while some seem to have no business being inside there at all. The parts of our body need blood in order to work properly – blood transports the nutrients each cell needs, and takes away any rubbish. The human body is everything that makes up, well, you. It protects us from the outside world, and is our first defense against bacteria, viruses and other pathogens. (Even the kangaroo, which hops on two legs when moving rapidly, walks on four legs and uses its tail as a “third leg” when standing.) They are made up of tissues. (6) The excretory system, composed of the kidneys, ureters, urinary bladder, and urethra, removes toxic nitrogen compounds and other wastes from the blood. Each day, the kidneys process about 200 quarts (50 gallons) of blood to filter out about 2 quarts of waste and water. For information on the structure and function of the cells that constitute the body, see cell. Intestine, Lg. Our editors will review what you’ve submitted and determine whether to revise the article. . Other mineral constituents of the body, found in minute but necessary concentrations, include cobalt, copper, iodine, manganese, and zinc. Examples of organs include the eyes, heart, lungs, liver, and stomach. Younger primary students may have little knowledge about internal bodily organs. So also is collagen, the fibrous, elastic material that makes up much of the body’s skin, bones, tendons, and ligaments. Chief among these are calcium, phosphorus, sodium, magnesium, and iron. The respiratory system allows us to take in vital oxygen and expel carbon dioxide in a process we call breathing. Human body internal parts such as the lungs, heart, and brain, are enclosed within the skeletal system and are housed within the different internal body cavities. Giving the body its shape is the skeleton, which is composed of cartilage and bone. It is responsible for the reproduction, … A group of cells from a tissue and a group of tissues form an organ.. A group of organs makes up an organ system and a group of organ systems make up the human body.. Thank you for signing up to Live Science. https://www.britannica.com/science/human-body, LiveScience - The Human Body: Anatomy, Facts and Functions, human body - Children's Encyclopedia (Ages 8-11), human body - Student Encyclopedia (Ages 11 and up). Thus, the heart is an organ composed of all four tissues, whose function is to pump blood throughout the body. The nervous system controls both voluntary action (like conscious movement) and involuntary actions (like breathing), and sends signals to different parts of the body. The lymphatic system includes lymph nodes, lymph ducts and lymph vessels, and also plays a role in the body's defenses. Updates? (8) The endocrine system, composed of the hormone-secreting glands and tissues, provides a chemical communications network for coordinating various body processes. Like lipids, proteins are an important constituent of the cell membrane. The teeth are also part of the skeletal system, but they aren't considered bones. The chief constituents and prime functions of each system are summarized below. The physical being called a person consists of 11 distinct human body systems, all of them vital for life, and their functions often reflect their names: cardiovascular, digestive, endocrine, integumentary, lymphatic, muscular, nervous, reproductive, respiratory, skeletal and urinary. Water is found in the extracellular fluids of the body (the blood plasma, the lymph, and the interstitial fluid) and within the cells themselves. The cardiovascular system is one that circulates the blood in the body. Urethra. Human body parts comprise a head, neck and four limbs that are connected to a torso. During conception, a sperm cell fuses with an egg cell, which creates a fertilized egg that implants and grows in the uterus. Cells – the basic unit of life Tissues – clusters of cells performing a similar function Organs – made of tissues that perform one specific function Organ Systems – groups of organs that perform a specific purpose in the human body Phospholipids and the steroid compound cholesterol are major components of the membrane that surrounds each cell. It consists mainly of the trachea, the diaphragm and the lungs. As intelligent as are many other mammals—such as chimpanzees and dolphins—none have achieved the intellectual status of the human species. The human body consists of trillions of cells, each capable of growth, metabolism, response to stimuli, and, with some exceptions, reproduction. Its main job is to make is to make and move lymph, a clear fluid that contains white blood cells, which help the body fight infection. Human body parts and their functions in tamil. The human body collectively is the most complex machine known to man, Like any machine, the human body is made of different body parts situated in some particular way with the goal of performing some function. (7) The nervous system, composed of the sensory organs, brain, spinal cord, and nerves, transmits, integrates, and analyzes sensory information and carries impulses to effect the appropriate muscular or glandular responses. When one considers the relation of these subdivisions of the skeleton to the soft parts of the human body—such as the nervous system, the digestive system, the respiratory system, the cardiovascular system, and the voluntary muscles of the muscle system —it is clear that the functions of the skeleton are of three different types: support, protection, and motion. The digestive system consists of a series of connected organs that together, allow the body to break down and absorb food, and remove waste. The diagram shows five levels of organization in a multicellular organism. Editor’s Note: If you’d like more information on this topic, we recommend the following book (available on amazon.com): Stay up to date on the coronavirus outbreak by signing up to our newsletter today. speaking, walking, or writing) requires skeletal muscle. It includes lymph nodes, the spleen, bone marrow, lymphocytes (including B-cells and T-cells), the thymus and leukocytes, which are white blood cells. The peripheral nervous system consists of nerves that connect every other part of the body to the central nervous system. Carbohydrates are present in the human body largely as fuels, either as simple sugars circulating through the bloodstream or as glycogen, a storage compound found in the liver and the muscles. Cells in a human body are of different types based on their structure and function. The … The heart keeps blood pumping throughout our body – the heart is one of our vital organs, which means it helps keep us alive. The pharynx (throat) is the transition area from the mouth to the esophagus. Typical of mammalian structure, the human body shows such characteristics as hair, mammary glands, and highly developed sense organs. Your body uses hormones to control growth, development, metabolism, reproduction, mood, and other functions. In addition, such extracellular materials as hair and nails are composed of protein. In addition to detoxifying poisonous substances, it also manufactures proteins and hormones. … It also functions to regulate the volume of fluid and the electrolyte balance in the body, ensuring homeostasis is maintained. It … The cell is the basic living unit of the human body—indeed, of all organisms. The female reproductive system consists of the vagina, the uterus and the ovaries, which produce eggs. The church has many members, yet remains one body, and each member plays a vital role. New York, Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. This article contains a list of organs of the human body. Different parts of the body in English with body parts pictures and examples. (2) The musculoskeletal system (also referred to separately as the muscle system and the skeletal system), composed of the skeletal muscles and bones (with about 206 of the latter in adults), moves the body and protectively houses its internal organs. Ready for Med School? For example, see abdominal cavity; adrenal gland; aorta; bone; brain; ear; eye; heart; kidney; large intestine; lung; nose; ovary; pancreas; pituitary gland; small intestine; spinal cord; spleen; stomach; testis; thymus; thyroid gland; tooth; uterus; vertebral column. The dorsal nerve cord is the spinal cord in humans; it remains throughout life. Many organs also depend on several other body parts. So, if an organ is damaged, it means the cells and cell structure in the organ are also damaged. (4) The circulatory system, composed of the heart, blood, and blood vessels, circulates a transport fluid throughout the body, providing the cells with a steady supply of oxygen and nutrients and carrying away waste products such as carbon dioxide and toxic nitrogen compounds. The next level of organization in the body is that of the organ. (3) The respiratory system, composed of the breathing passages, lungs, and muscles of respiration, obtains from the air the oxygen necessary for cellular metabolism; it also returns to the air the carbon dioxide that forms as a waste product of such metabolism.