Answer:
Explanation:
Compact bone aka cortical bone is a dense, solid and rigid in which bony matrix with ground org. Substances and salts densely filled and leave tiny spaces known as lacunae. These spaces contain osteocytes also called as bone cells. Inside of these osteons there is a central canal which supplies blood vessels and nerves within bone. These vessels provide blood to the spongy bone and living cells housed within compact bones.
Structure of Compact bone: Basic unit of Compact bone is called osteon also known as haversian system. Each osteon consist of four parts.
1. Haversian canal which consists blood vessels and nerves acts as a site of hematopoiesis which is one of the functions of Compact bone.
2.lamellae are concentric rings of strong matrix consisting Calcium and phosphorus. this gives the bone its strength and hardness to bear body weight.
3.Lacunae contains osteocytes.
4.Canaliculi links osteocytes and provide route for nutrients to reach osteocytes.
Answer:
The nervous system
Explanation:
The nervous system comprises the central nervous system, consisting of the brain and spinal cord, and the peripheral nervous system, consisting of the cranial, spinal, and peripheral nerves, together with their motor and sensory endings.
Answer is B. Heliotropism
The distance between points (-2,-11) and (-2,22) is D. 13 units.
