Biology
Human Skeletal System
Human Skeletal System
The Human Skeletal System consists of bones, cartilage, tendons and ligaments. It supports the body and protects the internal organs like heart, lungs, brain etc. It helps in movements of the body. It stores minerals like calcium and phosphate. It helps in production of blood cells. An adult has 206 bones. The male skeleton is generally longer and has a high bone mass. The female skeleton has a broader pelvis. The study of the structure and functions of the skeleton is called osteology.
Parts of skeletal system
• Axial skeleton
• Appendicular skeleton
Axial skeleton (80 bones)
• Vertebral column has 24 vertebrae, the sacrum bone and the coccyx (tail bone), a total of 26 bones. Out of 24 vertebrae, 7 are in the head and neck and are called cervical vertebrae, 12 are in upper back and are called thoracic vertebrae, 5 are in lower back and are called lumbar vertebrae.
• Thoracic cage has 12 pairs of ribs and sternum (breastbone), amounting to a total of 25 bones
• Skull has 8 cranial bones protecting brain and 14 facial bones found on face. Thus there are a total of 22 skull bones
Auditory ossicles
• They are small bones found within the inner ear canal in the skull
• 3 auditory ossicles namely malleus, incus and stapes are there in left inner ear canal and 3 on the right amounting to a total of 6 bones
Hyoid
• U-shaped bone found at base of jaw
• It is the point of attachment for muscles and ligaments in the neck
Appendicular skeleton (126 bones)
• Pectoral girdle is where the arms attach to the axial skeleton. Clavicle (collar bone) and scapula (shoulder blade) on left and right side
• Pelvic girdle is where the legs attach to the axial skeleton. One hip bone on the left side and one on the right side
• Upper limbs has 30 bones on each side amounting to a total of 60 bones
• Lower limbs has 30 bones on each side amounting to a total of 60 bones
Each upper limb (30 bones)
• Phalanges are 14 bones of fingers
• Carpals are 8 bones of wrist
• Metacarpals are 5 bones of middle area of hand
• Ulna is long bone of forearm running from elbow to the pinky finger side
• Radius is long bone of forearm running from elbow to the thumb side
• Humerus long bone of upper arm
Each lower limb (30 bones)
• Phalanges are 14 bones of toes
• Tarsals are 7 bones of ankle
• Metatarsals are 5 bones of middle area of foot
• Tibia is the larger, stronger bone connecting the knee with the ankle
• Fibula (calf bone) is on the lateral side of tibia, to which it is connected above and below
• Femur is the large bone of upper leg
• Patella is the knee cap
Maintain skeletal health
• Exercise
• Get vitamin D from sunlight
• Eat calcium rich foods like leafy green vegetables, broccoli etc.