Question

Calcium hydroxyapatite is a major component of
(a)Muscle fibre
(b)Bone
(c) Cartilage
(d)Nerve cells

Answer 1

Hint: It is a naturally occurring mineral form of calcium apatite and is usually denoted as the crystal unit cell which is composed of two entities. It crystallizes in the hexagonal crystal system and its powder is white. They are found in the small calcifications in the pineal gland and other structures known as brain sand or corpora arenacea.

Complete answer:
Calcium hydroxyapatite is a major component of bone that is made up of inorganic mineral hydroxyapatite including Calcium phosphate, calcium fluoride, calcium carbonate, and citrate. It helps to reduce bone loss and is easily absorbed by calcium source. Bone is a rigid organ that constitutes the part of the vertebral skeleton in humans. It provides support and structure to the body and enables mobility. They are lightweight and strong and hard to serve multiple functions. It is a hard tissue that is dense connective tissue and has a honeycomb-like Matrix internally which helps to provide bone rigidity. The mineralization in bones is formed by the osteoblast and osteocytes.

Additional Information: Muscle fibre: They are the result of an alignment or fusion of myoblast that arises from mesodermal somites. They are present within the muscle and are the fibres belonging to other MUs. The number of muscle fibres that are supplied by one motor neuron varies for different muscles. It can range from 30:1 to 120:1. The muscle fibres are related to the spatial distribution of endplates by the MUP and help in impulse propagation in the terminal nerve ending.
Cartilage: It is a flexible tissue that is the type of connective tissue in the body. It is present in around 60 to 80% and is composed of water. It decreases in older people and the rest is a jelly-like substance known as the matrix that gives its form and function.
Nerve cells: Nervous system comprises types of nerve cells that are the neurons and the glial cells. It is the structural and functional unit of The Nervous system and transmit electrical signals that are known as nerve impulses.
So, the correct answer is 'bone'.

Note: The human body comprises 206 bones of which 200 bones are of the skeleton. The smallest bone in the body is in the year and the longest bone is in the leg. There are millions of nerve cells in the human body and about a hundred billion in the brain and 13.5 million in the spinal cord.