The Tissue Level Of Organization - Chapter questions - Problem 10CP

Exocrine glands are classified into three main types: merocrine glands, holocrine glands, and apocrine exocrine glands, based on their manner of secretion. Secertory products are made in the endoplasmic reticulum and processesed and packaged by the golgi body, In merocrine glands the secretory vesicles move to the apical surface of the cell and the secretion is released by exocytosis. The salivary glands are merocrine glands and some merocrine glands are to be found in the pancreas; sweat glands also are merocrine glands. Halocrine glands are the second category of exocrine glands. In these glands the secretory product accumulates in the cytoplasm but eventually the entire cell becomes the secretory product, Eventually the entire secretory cell collapses and spill the secretory product together with plam membrane and intercellular membranes. The sebaceous glands, and eyelid glands are holocrine glands, Last , is the category of apocrine ecocrine glands, In these glands the secretory product acccumulates in the apical portion of the gland cells. That upper region then pinches off by exocytosis and releases its secretions. The lowerpart of these cells recover and repeats the process several times.Mammary glands are apocrine glands and move to the apical section of the cell. The apical portion of the cell then separates by exocytosis and releases the secretion. -- the rest of the recovers , is repaired and repeats the secretory process again and again, The last category of exocrine glands and the gland secretes by the collapse of the whole secretory cell . As a consequebce haolucrine secretions also contain both plasma membranes and intercellular membranes . Examples of holocrine glands are sebaceous glands