Chp 6 1

Recent questions

• What is the skeletal system made of?

  The skeletal system is primarily composed of bone tissue and cartilage. In fetuses, the skeleton initially forms from cartilage, which is gradually replaced by bone through a process known as ossification. By the time of birth, most of the skeleton consists of bone, although some cartilage remains in adults. The skeletal system serves various functions, including support, protection of vital organs, and facilitating movement through muscle attachment. It also plays a role in mineral storage, particularly for calcium and phosphorus.

• How do bones support the body?

  Bones support the body by providing a rigid framework that maintains its shape and structure. They serve as the primary support system for the body, allowing for upright posture and the ability to bear weight. Additionally, bones protect vital organs, such as the brain, heart, and lungs, by encasing them in a hard structure. The skeletal system also facilitates movement by serving as attachment points for muscles, enabling the body to perform various physical activities. Overall, the support provided by bones is crucial for both stability and mobility.

• What are the types of cartilage?

  There are three main types of cartilage: hyaline cartilage, elastic cartilage, and fibrocartilage. Hyaline cartilage is the most common type and is found at the ends of long bones, in the ribs' attachment to the sternum, and in structures like the larynx and nose. Elastic cartilage, which is more flexible, is located in the external ear and the epiglottis. Fibrocartilage is the toughest type and is found in areas that require support and strength, such as intervertebral discs, the knee meniscus, and the pubic symphysis. Each type of cartilage serves specific functions in the body, contributing to the overall structure and flexibility of the skeletal system.

• What is the function of bone marrow?

  Bone marrow serves several critical functions, primarily related to the production of blood cells. Red bone marrow is responsible for hematopoiesis, the process of forming red blood cells, white blood cells, and platelets. It is found in the proximal epiphyses of long bones and in the spongy bone of flat bones. As individuals age, red bone marrow is gradually replaced by yellow bone marrow, which primarily serves as a fat storage site. The presence of bone marrow within the skeletal system is essential for maintaining healthy blood cell levels and supporting the body's overall metabolic functions.

• How are bones classified by shape?

  Bones are classified into five main categories based on their shape: long bones, short bones, sesamoid bones, flat bones, and irregular bones. Long bones, such as the humerus and femur, are characterized by a long shaft and are primarily involved in movement. Short bones, like the carpal and tarsal bones, are roughly cube-shaped and provide stability and support. Sesamoid bones, such as the patella, are small bones embedded within tendons. Flat bones, including the sternum and skull bones, serve protective functions and provide surfaces for muscle attachment. Irregular bones, like the vertebrae and pelvis, have complex shapes that fulfill various roles in the body. This classification helps in understanding the diverse functions and structures of bones within the skeletal system.