Glandular tissues produce chemical substances. According to the Davidson College Biology Department, many glandular tissues secrete hormones, but others secrete substances such as sebum, saliva and vaginal lubrication. There are two categories of glandular tissue. Endocrine tissue releases substances into the bloodstream, and substances secreted by exocrine tissues travel through ducts to reach the body's outer surface or interior cavities such as the mouth and vagina.Continue Reading
The University of Leeds Histology Guide states that endocrine glands include the adrenal glands, thyroid, thymus and pituitary glands. Secretions made by these glands pass directly into the bloodstream. Exocrine secretions, such as those produced by the sweat, salivary and mammary glands, pass through ducts to reach their final destination.
Exocrine glandular tissue produces one of three secretion types. Sebaceous tissue produces sebum, a white, oily substance that lubricates the skin and traps moisture beneath its surface. The ducts through which sebum passes are called pores. Mucous tissues secrete heavy, viscous liquids such as the mucosal lining of the stomach. Mucous tissues are vital because they protect other delicate tissues from harsh substances such as stomach acid. The third type of exocrine glandular secretions is serous fluids, which are thin and watery. Saliva is an excellent example, although it also contains tiny amounts of mucous. Serous fluid is also an important component of blood.Learn more about Glands & Hormones
According to John Barrymore for HowStuffWorks, dermal fillers are injectable substances designed to mimic the function of subcutaneous fats and tissues. As people age, these tissues and fats break down and cause the face to seemingly sink in, appearing flatter and more hollow. Dermal fillers are injected into affected areas of the face to raise the skin and create the illusion of a plumped-up, youthful appearance.Full Answer >
The main function of capillaries is enabling the exchange between water, oxygen, carbon dioxide, nutrients and many other substances between blood and the surrounding tissues. The capillaries also connect the arterioles and venules to create uninterrupted blood flow through the body.Full Answer >
According to the National Center for Biotechnology Information, the primary function of the circulatory system is to pass substances back and forth between blood and the body's tissues. The NCBL notes this system is also called the "cardiovascular system."Full Answer >
A positron emission tomography scan is conducted by administering a radioactive tracer chemical to the patient and using a full-body scanner to detect how the substance interacts with tissues, organs and blood, states MedlinePlus. The radioactive signals tracked by the scanner are converted into electronic images.Full Answer >