Question

The hardest substance of the body is?
(a) Bone
(b) Enamel
(c) Cartilage
(d) Tendon

Answer 1

Hint: Those substances which are made by calcium minerals will be the hardest.
Hard tissue also known as calcified tissue are those tissues that are mineralized and have a firm intercellular matrix.

Complete answer:
The enamel of the tooth is the hardest substance in the body, it is the most highly mineralized substance.
Enamel is the outer covering of the teeth and is the most visible part of the teeth.

Additional information:
1. Tooth enamel is mostly made up of hydroxyapatite, which is a mineral form of calcium phosphate. On the Mohs hardness scale, this mineral shows a mark five thus making it the hardest substance in living beings.
2. The tooth enamel has a shiny, white resilient surface which is made up of 96% mineral, the highest percentage of any tissue in the body, thus making it durable and damage-resistant.
3. If the teeth are broken, they cannot heal back unlike bones as they do not have the same regenerative powers to grow back.
4. Each tooth's stem cells produce new dentin, to repair the damage however it has its limits and can manufacture only a small amount of tissue, catering to smaller damage only.
5. Bone is the second hardest tissue in the body After the dental enamel.
So, the correct answer is ‘Enamel’.

Note: Humans have 32 sets of teeth, out of which the teeth located at the end called molars are the strongest and widest teeth. They are 12 in number, six on top and six on the bottom. They help in grinding food and finish chewing before swallowing.