Discuss the bone under the following headlines: Composition, type, parts and structure.

Bones are composed of two types of tissue:

1. Compact (cortical) bone: A hard outer layer that is dense, strong, and durable. It makes up around 80 percent of adult bone mass.

2. Cancellous (trabecular or spongy) bone: This consists of a network of trabeculae or rod-like structures. It is lighter, less dense, and more flexible than compact bone.

Also found in bones:

osteoblasts and osteocytes, responsible for creating bone

osteoclasts or bone resorbing cells

osteoid, a mix of collagen and other proteins

inorganic mineral salts within the matrix

nerves and blood vessels

bone marrow

cartilage

membranes, including the endosteum and periosteum

Explanation:

answer: - b cells

explanation: -

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.