Isthmus

Definition

An isthmus is a narrow strip of tissue connecting two larger parts of an organ or structure. In the endocrine system, it specifically refers to the part of the thyroid gland connecting its two lobes.

5 Must Know Facts For Your Next Test

1. The isthmus of the thyroid gland connects the right and left lobes.
2. Located anterior to the trachea, it typically spans across the second and third tracheal rings.
3. It plays a role in maintaining thyroid hormone distribution between lobes.
4. Variations in the size or presence of the isthmus can occur among individuals.
5. Its involvement in endocrine function is crucial for metabolic regulation.

Review Questions

• What anatomical structures does the isthmus of the thyroid gland connect?
• Where is the thyroid gland's isthmus located relative to the trachea?
• Why is the isthmus important for thyroid hormone distribution?

Related terms

Thyroid Gland:

The butterfly-shaped endocrine organ located in front of the neck that secretes hormones regulating metabolism.

Larynx: The voice box located above where air enters, playing a key role in breathing and vocalization.

Trachea:

The windpipe that connects the larynx to the bronchi, providing air passage to and from the lungs.