Question

Cartilage is not found in
A) Nose
B) Ear
C) Kidney
D) Larynx

Answer 1

Hint: Cartilage is a flexible, resilient and smooth elastic tissue which is like a rubber pad covering and protecting the ends of long bones at joints and nerves. It has a fibrous covering layer called Perichondrium. And kidneys are basically a pair of beans shaped organs.

Complete answer:
As we have learnt till now that cartilage is a flexible, resilient and smooth elastic tissue which protects the ends of long bones at joints and nerves acting like rubber pad. It consists of a dense network of collagen fibres and elastic fibres.

A covering of dense irregular connective tissue called Perichondrium surrounds the surface of most cartilages. Perichondrium is composed of two layers, one is the outer fibrous layer and the other is inner cellular layer. The inner cellular layer of Perichondrium is germinative in nature and gives rise to immature cells called Chondroblasts which further matures into the Chondrocyte cells of the cartilage. These cartilage cells are found within a fluid filled Lacunae and the matrix of cartilage consists of fibres and a protein called Chondrin.
Cartilages are classified as three main types namely
- Hyaline cartilage
- Fibrocartilage
- Elastic cartilage.

Let us talk about them. Hyaline cartilage is the most abundant type and has a bluish-white translucent matrix with fine collagen fibres. It is located in the ends of bones, anterior end of ribs, nose, Larynx part, trachea, bronchi etc.

Fibrocartilage is the strongest and toughest cartilage found in intervertebral disc and pubic symphysis.
Lastly the Elastic cartilage which consists of chondrocytes present within an extracellular matrix in a threadlike network of elastic fibres. It is mainly found in epiglottis, auricle: part of the external ear and Eustachian tubes.

Hence from the above explanation we can say that cartilage is found in Nose, Ear and Larynx. And also Kidney is enclosed in a fibrous connective tissue and is made of functional units called nephrons,where one can say that the cartilage is not present in the kidneys.

Therefore the correct answer is option (C).

Note: Cartilage does not have a blood supply because it secretes an antiangiogenesis factor which is a substance that prevents blood vessel growth. Perichondrium does have nerves and blood vessels so it is an exception in the cartilages.