What Do You Know About Bones?

1. Your height changes; you grow constantly until you are a teenager. There is a growth plate in the upper part of the bone where new cells are produced constantly, aiding in the growth of the bone.
2. All joints in the body are covered with cartilage. Cartilage is a spongy layer of tissue composed of water, collagens, proteoglycans, and cells. Gravity compresses the cartilage, particularly in your spine, during a day when you are walking or standing.
3. The bone plates that make up your skull connect at joints. The skull joints, however, do not move like other movable joints where bones connect, such as the knee.
4. Your thigh has a long and the strongest bone, the femur. it can withstand stresses of up to 2500 pounds.
5. Although the femur is a difficult bone to break. Most people break a toe bone. Mild to moderate toe fractures are treated by taping the fractured toe to the adjacent toe. Severe fractures may need a cast or sometimes surgery.
6. All bones are connected to another bone except for the hyoid bone near the thyroid gland. It is not connected to any bone in the body.
7. Bones protect the organs of the body. The skull protects the brain and shapes the face. The backbone or spinal column protects the spinal cord, which serves as a conduit for communications between the brain and the body. The ribs create a cage that protects the heart and lungs, whereas the pelvis protects the bladder, part of the intestines, and reproductive organs.
8. Although bones are strong, tooth enamel is the body's strongest and toughest component.
9. Bone marrow is a spongy substance that fills the insides of most bones. Bone marrow generates red blood cells that transport oxygen throughout the body. Marrow produces about 2,000,000 red blood cells per second. It produces other blood cells, such as:
   • Lymphocytes or white blood cells
   • Platelets
10. Bone collagen is continually replenished, and it is a lifetime biological activity. Every year, about 10 percent of bone is replaced. You receive a new skeleton every 10 years because the mineral composition in your bones is regenerated.
11. Three bones link at the knee joint, femur, tibia, and patella. To link these three massive bones, an equally massive joint is required. Because of this, the knee is the biggest joint in your body.
12. The malleus (hammer), incus (anvil), and stapes (stirrup) bones are the smallest bones in the human body. These bones are collectively called the ossicles, and their function is to convey sound vibrations from the air to the fluid in the inner ear.
13. The finding of a bone tumor in a Neanderthal rib 120,000 years ago established the existence of bone malignancies.
14. Prostheses are manmade structures that replace missing or damaged bodily components. Ancient Egyptians are the first to develop a functional prosthetic for the big toe.
15. Smoking can cause bone density loss, often called osteoporosis. As you age, existing bone breaks down quicker than new bone grows. This develops gaps in the bones and makes them weaker, a condition called osteoporosis. Loss of height, fracture following a fall, or back and neck pain are symptoms of advanced osteoporosis. Eight million or 80 percent of the estimated 10 million Americans with osteoporosis are women. One in every two women older than 50 years will break a bone because of osteoporosis.
16. Bone fractures are not common in children. However, if fractured, children's bones recover faster than adults’ bones. When your bones shatter, your body goes into overdrive to mend the injury. A blood clot grows around the breach within a few hours. Following that, a soft callus comprised largely of collagen forms around the fracture, and two weeks later, a hard callus forms. This process can take anywhere between 6 and 12 weeks depending on your age and condition.
17. All bones in males and females are almost alike except for the pelvic bone. The pelvic bone may be used to identify the gender of a skeleton.
18. Until the age of 30 years, your bone density increases. Then, unless you receive enough exercise, calcium, and vitamins A, K, and D from your diet, your density will fall. What makes healthy bones the healthiest are the nutrition they require and regular activity even daily walks.

Depending on the shape and functionality, bones are divided into five types.

1. Long bones: Long bones are largely compact bones with minimal marrow and comprise most of the bones in the limbs. The following bones sustain weight and aid in movement:
   • Femur (thigh bone)
   • Humerus (upper arm bone)
   • Phalanges (bones of fingers and toes)
2. Short bones: Short bones include only a thin layer of compact bone and comprise the wrist and ankle bones.
3. Flat bones: Flat bones are often thin and bent bones. They are made up of two layers of compact bone on the outside and an inner layer of spongy bone on the inside. The flat bones are the:
   • Skull bones
   • Sternum or breastbone
   • Ribs
4. Irregular bones: Irregular bones are bones that do not fall into the first three categories and have an irregular form. They include the spine and pelvic bones. They serve to protect organs or tissues. The examples include:
   • Vertebrae
   • Pelvic bone
   • Bones of the face
5. Sesamoid bones: Sesamoid bones are implanted in tendons that connect muscle to bone, such as the patella or kneecap. They shield tendons from wear and tear, as well as relieve pressure when a joint is used. Surprisingly, their positioning varies with people.

1. Compact (cortical) bone: A compact, robust and long-lasting outer layer of bone. It accounts for over 80 percent of mature bone mass.
2. Cancellous (trabecular or spongy) bone: A network of trabeculae or rod-like structures makes up this type of bone. It is less thick, lighter, and more flexible than compact bone.

7 other components of the bone

1. Various bone cells
2. Osteoid, a mix of collagen and other proteins
3. Inorganic mineral salts within the matrix
4. Nerves and blood vessels
5. Bone marrow
6. Cartilage
7. Membranes, including the endosteum and periosteum

Bone cells responsible for the formation of bones are osteoblasts and osteocytes, whereas osteoclasts are responsible for the resorption (breaking down) of the bone.

1. Osteoblasts: Osteoblasts are responsible for the formation of new bones and the healing of existing bones. Osteoblasts create an osteoid protein combination, which is mineralized and produces bone. They produce hormones, such as prostaglandins.
2. Osteocytes: Osteocytes are dormant osteoblasts that have been imprisoned in the bone they have formed. They keep in touch with other osteocytes and osteoblasts. They are necessary for bone tissue communication.
3. Osteoclasts: Osteoclasts are huge cells that have many nuclei. It is their function to break down bone. They secrete enzymes and acids that break down and digest minerals in the bone. This is called resorption. Osteoclasts help remodel broken bones and the formation of channels for nerves and blood vessels to flow through.