Which of the following are usually present in connective tissue?

• A. Chondrocytes and myofibrils
• B. Keratinocytes and melanin
• C. Neurons and glial cells
• D. Fibers, ground substance, and cells

Answer: (D)

Verified step by step guidance

1. Understand the components of connective tissue: Connective tissue is one of the four main types of tissue in the body. It is characterized by three primary components: fibers, ground substance, and cells. These components work together to provide structural support, protection, and other functions.
2. Define fibers: Fibers in connective tissue include collagen fibers (providing strength), elastic fibers (allowing flexibility), and reticular fibers (forming supportive networks). These fibers are essential for the mechanical properties of connective tissue.
3. Explain ground substance: Ground substance is the amorphous, gel-like material that fills the space between cells and fibers in connective tissue. It is composed of water, glycosaminoglycans, proteoglycans, and glycoproteins, which help in nutrient diffusion and provide a medium for cellular communication.
4. Identify the types of cells: Connective tissue contains various types of cells, such as fibroblasts (which produce fibers and ground substance), adipocytes (fat storage cells), macrophages (immune defense), mast cells (involved in inflammation), and chondrocytes (found in cartilage). These cells contribute to the diverse functions of connective tissue.
5. Compare the incorrect options: Chondrocytes are specific to cartilage, myofibrils are part of muscle tissue, keratinocytes and melanin are associated with the epidermis, and neurons and glial cells are components of nervous tissue. None of these are characteristic of connective tissue, which is defined by fibers, ground substance, and cells.