In the classic 1975 british comedy film “Monty Python and the Holy Grail,” King Arthur battles a mysterious Black Knight who refuses to let him pass. Arthur handily vanquishes his foe by cutting off his limbs one by one, all while the knight, reluctant to admit defeat, insists the damage is only a flesh wound.
Dark humor aside, it raises the question of just how much of your body you could lose and still survive. Of the roughly 80 organs in the human body, only five are defined as vital organs that are crucial for sustaining life: the brain, which orchestrates bodily functions; the lungs and heart, which take in and distribute the oxygen cells need throughout the body; the liver, which has crucial roles in digestion and blood detoxification; and the kidneys, which filter waste and excess fluid from the body.
Other important structures that are not traditionally considered vital organs include the intestines, which absorb nutrients from food; the pancreas, which makes essential hormones like insulin; and the skin, which guards against infection, according to Human Skeleton: Anatomy and Function
Table of Contents The human skeleton is the internal framework of the human body, consisting of 206 bones in the adult, providing support, protection, and enabling movement. The skeletal system has multiple crucial functions.It supports the body, protecting vital organs like the brain (cranium), heart and lungs (rib cage), and spinal cord (vertebral column). It also facilitates movement by providing attachment points for muscles. Furthermore, bone marrow within bones produces blood cells, and bones serve as a reservoir for minerals like calcium and phosphorus. For example, the femur, or thigh bone, is the longest and strongest bone in the human body, capable of withstanding significant stress during activities like walking, running, and jumping.Kenhub provides detailed anatomical data. Bones are composed of approximately 50% water, 25% collagen, and 25% mineral salts, primarily calcium phosphate. There are five main types of bones: long,short,flat,irregular,and sesamoid. Long bones, like the femur and humerus, are longer than they are wide and function as levers. short bones,such as the carpals and tarsals,are cube-shaped and provide stability and support. Flat bones, including the skull bones and ribs, are thin and often curved, protecting organs and providing a large surface area for muscle attachment.Irregular bones, like the vertebrae, have complex shapes. Sesamoid bones, like the patella (kneecap), are embedded in tendons. According to the National Institutes of Health, bone remodeling is a continuous process involving bone resorption (breakdown) and bone formation, ensuring bone strength and adaptation to stress. The human skeleton can be divided into two main divisions: the axial skeleton and the appendicular skeleton. The axial skeleton (80 bones) includes the skull, vertebral column, ribs, and sternum. The skull protects the brain and supports facial structures. The vertebral column, or spine, supports the body and protects the spinal cord.The ribs protect the thoracic organs, and the sternum provides attachment points for the ribs. The appendicular skeleton (126 bones) includes the bones of the limbs (arms and legs) and the girdles (shoulder and pelvic girdles) that attach the limbs to the axial skeleton. As an example, the human pelvis, formed by the ilium, ischium, and pubis, provides support for the trunk and protects the pelvic organs. Detailed information on skeletal anatomy can be found at Visible Body. Several conditions can affect the skeletal system, including osteoporosis, arthritis, and fractures. Osteoporosis is a condition characterized by decreased bone density, increasing the risk of fractures. Arthritis involves inflammation of the joints, causing pain and stiffness. Fractures are breaks in bones, often caused by trauma. Other conditions include scoliosis (curvature of the spine) and Paget’s disease of bone (disruption of bone remodeling). The National Bone Health Campaign, run by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), provides resources on preventing and managing skeletal conditions. As of January 17, 2026, NIAMS continues to fund research into osteoporosis and other bone diseases. Joints are the points where two or more bones meet, allowing for movement. There are three main types of joints: fibrous, cartilaginous, and synovial. Fibrous joints, like those in the skull, are immovable. Cartilaginous joints, such as those between vertebrae, allow for limited movement. Synovial joints, like the knee and elbow, are freely movable and contain synovial fluid to lubricate the joint. The Johns Hopkins Medicine details the diffrent types of joints and their functionsBone Composition and Types
Major Bones and Their Locations
Common Skeletal Conditions
Joints and Their Functions
