Explain how glands are classified.
Guide On Rating System
Vote
Glands can be classified in several ways based on different criteria. The most common classification of glands is based on their structure and mode of secretion.
1. Structure: Glands are classified into two main types based on their structure.
a) Exocrine glands: These glands secrete their products into ducts that transport the secretions to the surface of an epithelial tissue or directly into body cavities. Examples include sweat glands, salivary glands, and mammary glands. Exocrine glands can further be classified based on the type of secretion they produce, such as serous glands (secrete watery fluids), mucous glands (secrete mucus), and mixed glands (secrete a combination of both).
b) Endocrine glands: These glands do not have ducts and secrete hormones directly into the bloodstream. The hormones are then transported to target organs and tissues, where they elicit specific responses. Examples of endocrine glands include the pituitary gland, thyroid gland, and adrenal glands.
2. Mode of Secretion: Glands can also be classified based on their mode of secretion, which refers to how they release their secretions.
a) Merocrine glands: These glands release their secretions through exocytosis. The secretory vesicles fuse with the plasma membrane, releasing the contents into the duct or onto the surface of the tissue. Most exocrine glands, such as sweat and salivary glands, are merocrine glands.
b) Apocrine glands: These glands involve the shedding of portions of the cytoplasm itself to release secretions. Examples of apocrine glands are mammary glands, which secrete milk.
c) Holocrine glands: These glands release their secretions by the rupture and destruction of the entire cells. The cells accumulate the secretory product until they disintegrate, releasing the entire contents. Sebaceous glands in the skin are examples of holocrine glands.
In addition to these classifications, glands can also be classified based on their location, function, or the type of cell they are derived from.
Got a question with my answer?
Cheapmath.com is completely free!
Asking question is free.
Getting answers is free.
+99