QUESTION: Which tissue type forms glands?
ANS:
- Epithelial tissue forms glands.
- Epithelial tissue is one of the four main types of animal tissue.
- It is specialized for covering body surfaces and lining body cavities.
- Within epithelial tissue, there are specific cells that are modified to form glandular structures.
- Glands are structures that produce and secrete substances, such as hormones, enzymes, mucus, sweat, and oil.
- They can be classified into two main types based on their structure and mode of secretion:
- Exocrine Glands secrete their products into ducts that lead to body surfaces or cavities.
- Endocrine Glands secrete their products directly into the bloodstream, without the use of ducts.
- They produce hormones that regulate various bodily functions.
| Tissue Type | Description |
| Epithelial Tissue
|
· Specialized tissue that covers body surfaces and lines body cavities.
· Consists of closely packed cells with minimal extracellular matrix. · Functions in protection, secretion, absorption, and sensation. · Forms glandular structures for secretion of substances. · Can be classified into different types based on cell shape (e.g., squamous, cuboidal, columnar) and layer arrangement (e.g., simple, stratified). Examples of glands formed by epithelial tissue include · Sweat glands · Salivary glands · Sebaceous glands · Mammary glands |
| Glandular Structures | · Formed by modifications of epithelial cells within the epithelial tissue.
· Epithelial cells undergo structural changes to become secretory cells. · Glandular structures can be unicellular or multicellular. · Unicellular glands, such as goblet cells, are scattered within epithelial tissues and secrete mucus. · Multicellular glands consist of clusters of glandular cells organized into structures such as ducts and secretory units. · Glandular structures can be exocrine or endocrine glands. |
| Exocrine Glands
|
· Secrete their products into ducts that lead to body surfaces or cavities.
· Examples include sweat glands, salivary glands, sebaceous glands, and pancreas. · Glandular cells of exocrine glands produce substances that are transported through ducts and released onto body surfaces or into body cavities. · The ducts can be simple or branched, and the secretory units can be tubular, acinar (rounded), or a combination of both. |
| Endocrine Glands | · Secrete their products directly into the bloodstream, without the use of ducts.
· Examples include pituitary gland, thyroid gland, adrenal glands, and pancreas. · Glandular cells of endocrine glands produce hormones that are released into the surrounding interstitial fluid and then enter the bloodstream for distribution to target cells throughout the body · Endocrine glands are highly vascularized to facilitate hormone transport. |