Question

Question 51 10 pts Answer in complete sentences. • Explain how failure of hyaline cartilage to develop into bone may lead to short stature. Explain which type of ossification is affected and which bones are affected. Explain how an X-ray of the hand and wrist might be helpful in diagnosis of short stature. HTML Editor B I VA - A - I E331x x D N V GOY @ 11 12pt _ Paragraph

Answer 1

Ans. 1) during bone development hyaline cartilage are replaced by bone, this process is known as endochondral ossification. Bone at the base of skull and long bones are formed by this process. Some of the mesenchymal cells differentiate into chondrocytes, cartilage cells, that form the cartilaginous skeletal precursor of these bones.

During ossification, chondrocytes and cartilage continue to grow at the ends of the bone, which increases the bone’s length at the same time bone is replacing cartilage in the diaphyses. That's why faliure in hyaline cartilage development caur short stature as it is responsible for development of long bones.

Ans. 2) as explained above hyaline cartilage are involved in the development of long bones by the process called endochondral ossification.

For example, in a long bone, at about 6 to 8 weeks after conception, some of the mesenchymal cells differentiate into chondrocytes, cartilage cells, that form the cartilaginous skeletal precursor of the bones. Soon after, the perichondrium, a membrane that covers the cartilage, appears.

Endochondral ossification follows five steps:

• Mesenchymal cells differentiate into chondrocytes.
• Formation of the cartilage model of the future bony skeleton and the perichondrium.
• Capillaries penetrate cartilage. Perichondrium transforms into periosteum. Periosteal collar develops. Primary ossification center develops.
• Cartilage and chondrocytes continue to grow at ends of the bone.
• Secondary ossification centers develop.
• Cartilage remains at epiphyseal (growth) plate and at joint surface as articular cartilage.

This process occur in long bones.

Ans. 3) Bones such as those in the fingers and wrist, contain growing zones at both ends called growth plates. These plates consist of special cells responsible for the bone's growth in length. Growth plates are easy to spot on an X-ray because they are softer and contain less mineral, making them appear darker on an X-ray image than the rest of the bone.

As kids grow, growth plates change in appearance on the X-ray images and become thinner, eventually disappearing, this is what is called closed growth plates. Because they look different at each age, a doctor can assign a bone age based on the appearance of the bones and growth plates. The bone age study can help evaluate how fast or slowly a child's skeleton is maturing, which can help in diagnose conditions that delay or accelerate physical growth and development.