Difference Between Bone and Cartilage

Bone and cartilage are two specialized forms of connective tissues, integral to the difference between bone and cartilage class 9 curriculum, each with distinct features and functions. As a combination of bones and cartilages forms the framework of the vertebrate skeleton, understanding their differences is crucial.

What is Bone?

Bone is a living tissue that makes up the skeleton in humans and other vertebrates. It provides structure, protects organs, stores calcium, and anchors muscles. Bones support and enable movement, produce blood cells in the marrow, and release minerals necessary for bodily functions. They continuously remodel and adapt throughout life.

Structure & Composition of the Bones

• Material: Bones are primarily made up of a matrix of collagen fibers (organic part) and hydroxyapatite, a mineralized compound containing calcium and phosphate (inorganic part). This combination gives bones their strength and rigidity while allowing for some flexibility.
• Cell Types: The primary cells in bones are osteocytes (mature bone cells), osteoblasts (bone-forming cells), and osteoclasts (bone-resorbing cells).
• Structure: Bones are classified into two main types based on their texture: compact (dense) bone that forms the hard outer layer of all bones and spongy (cancellous) bone that is found inside bones and has a porous, honeycomb structure.

Functions of Bones

As a critical part of “Bone and Cartilage,” bones provide a framework that supports the body and maintains its shape. Delineated are some important functions of bones –

• Protection: Bones protect internal organs from mechanical damage. For example, the skull protects the brain, and the rib cage protects the heart and lungs.
• Movement: Bones serve as levers and attachment points for muscles. When muscles contract, they pull on bones, creating movement.
• Mineral Storage: Bones are a reservoir for minerals, especially calcium and phosphorus, essential for various body functions.
• Blood Cell Production: The marrow inside some bones is a major site for the production of blood cells, a process known as hematopoiesis.

What is Cartilage?

Cartilage is a thin, fibrous, flexible connective tissue found in areas like the external ear and respiratory tract, representing the versatility of Bone and Cartilage. Lacking blood vessels, its growth is slower.

Structure & Composition of the Cartilage

Cartilage is made up of specialized cells called chondrocytes that produce a large amount of extracellular matrix composed of collagen fibers, elastin fibers, and a gel-like ground substance. This composition gives cartilage its flexible and compressible properties.

Types of Cartilage

There are three main types of cartilage –

1. Hyaline Cartilage: The most common type, found in the nose, trachea, larynx, and at the ends of bones where they form joints. It provides smooth surfaces for the movement of joints and flexibility and support.
2. Fibrocartilage: A tough, dense type found in areas subjected to high pressure and strain, like the intervertebral discs and the menisci in the knee. It provides strong support and absorbs shock.
3. Elastic Cartilage: Contains elastic fibers and is found in areas that require flexibility and resilience, like the ear and epiglottis.

Functions of Cartilage

Cartilage provides structural support to various parts of the body, such as the ear and nose, maintaining their shape. Given below are the important functions of cartilage –

1. Shock Absorption and Load Distribution: In joints, cartilage acts as a cushion between bones, absorbing impact and distributing the load evenly to minimize damage.
2. Smooth Surface for Movement: Hyaline cartilage at joint surfaces enables bones to glide over each other smoothly, reducing friction and facilitating movement.
3. Growth and Development: In children and adolescents, cartilage plays a key role in the growth and lengthening of bones.

Unique Characteristics of the Cartilage – Avascular and No Nerves

• Avascular: Cartilage lacks blood vessels; nutrients and waste are exchanged via diffusion, which is why it heals slower than other tissues.
• No Nerves: Cartilage does not contain nerves, which is why joint damage can sometimes go unnoticed until there is significant wear or damage.

Difference Between Bone and Cartilage

This table provides an overview an the bone and cartilage difference. It encapsulates how a combination of bones and cartilages forms the structural and functional framework of the body.

Interesting Facts – Difference Between Bone and Cartilage Class 9

Bones and cartilage are integral parts of the human skeletal system, but they serve different purposes and have unique characteristics. Here are some interesting facts about bones and cartilage difference, highlighting their roles in the body:

Bones

1. Living Tissue: Bones are living, growing tissues that can repair themselves. They are made of a hard outer layer called cortical bone and a spongy inner layer known as cancellous bone, which contains bone marrow.
2. Calcium Storage: Bones are the main reservoir for calcium and phosphorus in the body. They release these minerals into the bloodstream as needed for various bodily functions.
3. 206 in Number: The adult human body typically has 206 bones, while babies are born with approximately 270 bones. Some of these bones fuse together as we grow.
4. Lightweight but Strong: Despite their strength, bones are surprisingly light. The design of the bone structure allows it to bear a considerable amount of weight relative to its weight.
5. Remodeling: Bone undergoes a continuous process of remodeling, where old bone tissue is replaced with new. This process helps repair micro-damages and reshapes bones during growth.

Cartilage

1. Flexible Connective Tissue: Unlike bone, cartilage is a flexible connective tissue found in various body parts, including the joints, ear, nose, and respiratory tract.
2. No Blood Supply: Cartilage does not contain blood vessels. It receives nutrients through diffusion, which is why it heals much more slowly than bone.
3. Types of Cartilage: There are three main types of cartilage – hyaline (the most common, found in the ribs, nose, and larynx), elastic (more flexible, found in the external ear), and fibrocartilage (very tough, found in intervertebral discs and menisci).
4. Shock Absorption: In joints, cartilage covers the ends of bones, providing a smooth, slippery surface that reduces friction and acts as a cushion to absorb impact.

Differences between Bones and Cartilage

1. Mineralization: Bones are heavily mineralized with calcium and phosphorus, making them hard and rigid. Cartilage, on the other hand, is not mineralized, which is why it’s flexible.
2. Growth Patterns: Bones grow through a process called ossification. Whereas cartilage is replaced by bone, cartilage grows by expanding from within (interstitial growth).
3. Repair and Regeneration: Bones have a better capacity for self-repair due to their blood supply. Cartilage, lacking a blood supply, regenerates very slowly and often incompletely.

Function in the Body: Bones provide structure, support, and protection to the body and facilitate movement. While also providing structure, cartilage primarily offers flexibility and cushions joints.

FAQs on Difference Between Bones and Cartilage

Which of the following is the correct difference between bone and cartilage?

A correct difference between bone and cartilage is that bone is hard and dense, providing structural support and protection, while cartilage is more flexible and provides cushioning and smooth surfaces for joint movement. Bone marrow is the soft tissue inside bones where blood cells are produced, whereas cartilage is a firm, flexible tissue that covers the ends of bones in joints and provides structural support.

How are bone marrow and cartilage different?

Cartilage and joints differ in that cartilage is a type of connective tissue providing cushioning and support within joints, while joints are the anatomical areas where two bones meet and are supported by cartilage, ligaments, and synovial fluid for movement

What are the four differences between bone and cartilage?

Four differences between bone and cartilage are: bone is rigid and dense, whereas cartilage is flexible; bone is vascular, while cartilage is avascular; bone cells are called osteocytes, whereas chondrocytes are in cartilage; bones can repair themselves, but cartilage has limited regenerative capacity.

What is common between bone and cartilage?

Common between bone and cartilage is that both are types of connective tissue that provide structural support to the body; both contain cells embedded in an extracellular matrix and play crucial roles in the skeletal system.

Why is bone stronger than cartilage?

Bone is stronger than cartilage because it contains minerals like calcium and phosphorus, which make it hard and rigid, capable of bearing weight and withstanding stress, unlike the more flexible and less dense cartilage.

Does cartilage become bone?

Cartilage does not become bone in the usual sense, but during growth, a process called endochondral ossification occurs where cartilage serves as a template and is gradually replaced by bone tissue in the developing fetus and growing children.

Which bone is called cartilage?

No bone is called cartilage as they are distinct types of tissues. However, in the context of certain conditions or development stages, cartilage can be transformed into bone through a process known as ossification, particularly during fetal development and childhood growth.