Microscopy Primer
Light and Color
Microscope Basics
Special Techniques
Digital Imaging
Confocal Microscopy
Live-Cell Imaging
Microscopy Museum
Virtual Microscopy
Web Resources
License Info
Image Use
Custom Photos
Site Info
Contact Us

The Galleries:

Photo Gallery
Silicon Zoo
Chip Shots
DNA Gallery
Amino Acids
Religion Collection
Cocktail Collection
Screen Savers
Win Wallpaper
Mac Wallpaper
Movie Gallery

Brightfield Microscopy Digital Image Gallery

Thyroid Gland

The thyroid is an endocrine gland situated in the throat that produces hormones that are involved in various functions within the body. Comprised of two oblong lobes linked by a narrow piece of tissue called the isthmus, the thyroid contains millions of small sac-like follicles that store the important substances.

View an image of the thyroid gland section at 10x magnification.

Within the thyroid follicles, hormones are stockpiled in the form of the glycoprotein thyroglobulin. Before the substances are secreted into the bloodstream through the capillaries, however, they are primarily converted into thyroxine, although smaller amounts of other related hormones are also generated. The quantity of the hormones that are produced chiefly depends upon the amount of thyroid-stimulating hormone released by the pituitary gland. Through an effective feedback mechanism the level of thyroxine within the body usually stays within a steady range, but various conditions, as well as an insufficient supply of iodine in the body, may result in too much or too little production, leading to a variety of disorders.

Though the specific effects of the hormones secreted by the thyroid are various, their most important role in adults is regulating metabolic processes. In children, thyroid hormones also play an essential role in proper growth and development. Thus, a deficiency in thyroid secretion in childhood is associated with both dwarfism and mental deficiencies. Goiter, a disease characterized by the enlargement of the thyroid gland to such an extent that a sizable lump appears at the front of the neck making swallowing and breathing difficult, is also caused by inadequate levels of thyroxine. Hyperthyroidism, or excessive secretion by the thyroid, however, is most commonly manifested as Gravesí disease.


Questions or comments? Send us an email.
© 1998-2022 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.
This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.
Last modification: Friday, Nov 13, 2015 at 02:19 PM
Access Count Since November 25, 2003: 42377
All of the images in this gallery were captured with a QImaging Retiga camera system.
For more information on these cameras, use the button below to access
the QImaging website:
Visit the QImaging website.
For more information on microscope manufacturers,
use the buttons below to navigate to their websites: