Question

Which of the following is holocrine secretion?
A) Mammary
B) Sebaceous
C) Pancreas
D) Sweat glands

Answer 1

Glands are important organs located throughout the body and they produce and release substances that perform certain functions. Glands are invaginations of epithelial tissue. They are divided into two main types as- Exocrine (secretion in the duct) and Endocrine glands (ductless glands). The holocrine glands secrete the secretions in the cytoplasm of the cell and the secretion is release by the bursting of the plasma membrane.

Complete answer:
The exocrine glands are the glands that secrete their secretion into a duct through which the secretion is transported to the target organs. Exocrine glands can also be categorised into 3 subtypes according to their secretion mechanism: Merocine glands, Apocrine glands and Holocrine glands.

- Merocrine glands are the most common and release their secretory products via exocytosis and the major secretory products of these glands are usually proteins. Example sweat glands.
- Apocrine glands release their secretory products contained within membrane-bound vesicles and this type of secretion is rare and these glands are found in the breast called the mammary gland and constitute some sweat glands.
- Holocrine glands release whole secretory cells and which later disintegrate to release the secretory products. This type of secretion is seen in sebaceous glands associated with hair follicles in the skin.
- The pancreas is an example of the endocrine gland. They secrete hormones Endocrine glands are the ductless glands that secrete their secretion directly into the bloodstream.

Thus, the correct answer is option ‘B’ i.e, Sebaceous Gland.

Note: The release of secretory products from the secretory unit is done with help of some contractile cells, known as myoepithelial cells. These cells comprise characteristics of both muscle and epithelial cells and lie between the secretory unit and basement membrane, their cytoplasmic processes envelop the secretory unit.