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Levator Muscle Of Thyroid Gland
A fibrous or muscular band is sometimes found attached, above, to the body of the hyoid bone, and below to the thyroid isthmus The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ..., or its pyramidal lobe. When muscular, it is termed the Levator muscle of thyroid gland. References External links * * Muscles of the head and neck {{muscle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyrohyoid Muscle
The thyrohyoid muscle is a small skeletal muscle on the neck. It originates from the lamina of the thyroid cartilage, and inserts into the greater cornu of the hyoid bone. It is supplied by the hypoglossal nerve, and a branch of the ventral rami of the cervical plexus, spinal nerve C1, which travels with the hypoglossal nerve. The thyrohyoid muscle depresses the hyoid bone and elevates the larynx. By controlling the position and shape of the larynx, it aids in making sound. Structure The thyrohyoid muscle is a quadrilateral muscle in shape. It appears like an upward continuation of the sternothyroid muscle. It belongs to the infrahyoid muscles group. It lies in the carotid triangle. It arises from the oblique line on the lamina of the thyroid cartilage. It is inserted into the lower border of the greater cornu of the hyoid bone. Nerve supply The thyrohyoid muscle is supplied by the hypoglossal nerve (XII). It is the only infrahyoid muscle that is not supplied by the ansa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid Isthmus
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thyroid is located at the front of the neck, below the Adam's apple. Microscopically, the functional unit of the thyroid gland is the spherical thyroid follicle, lined with follicular cells (thyrocytes), and occasional parafollicular cells that surround a lumen containing colloid. The thyroid gland secretes three hormones: the two thyroid hormones triiodothyronine (T3) and thyroxine (T4)and a peptide hormone, calcitonin. The thyroid hormones influence the metabolic rate and protein synthesis, and in children, growth and development. Calcitonin plays a role in calcium homeostasis. Secretion of the two thyroid hormones is regulated by thyroid-stimulating hormone (TSH), which is secreted from the anterior pituitary gland. TSH is regulated by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ansa Cervicalis
The ansa cervicalis (or ansa hypoglossi in older literature) is a loop of nerves that are part of the cervical plexus. It lies superficial to the internal jugular vein in the carotid triangle. Its name means "handle of the neck" in Latin. Branches from the ansa cervicalis innervate most of the infrahyoid muscles, including the sternothyroid muscle, sternohyoid muscle and the omohyoid muscle. Note that the thyrohyoid muscle, which is also an infrahyoid muscle and the geniohyoid muscle which is a suprahyoid muscle are innervated by cervical spinal nerve 1 via the hypoglossal nerve. Roots Two roots make up the ansa cervicalis, a superior root, and an inferior root. The superior root of the ansa cervicalis is formed from cervical spinal nerve 1 of the cervical plexus. These nerve fibers travel in the hypoglossal nerve before separating in the carotid triangle to form the superior root. The superior root goes around the occipital artery and then descends on the carotid sheath. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyoid Bone
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra. Unlike other bones, the hyoid is only distantly articulated to other bones by muscles or ligaments. It is the only bone in the human body that is not connected to any other bones nearby. The hyoid is anchored by muscles from the anterior, posterior and inferior directions, and aids in tongue movement and swallowing. The hyoid bone provides attachment to the muscles of the floor of the mouth and the tongue above, the larynx below, and the epiglottis and pharynx behind. Its name is derived . Structure The hyoid bone is classed as an irregular bone and consists of a central part called the body, and two pairs of horns, the greater and lesser horns. Body The body of the hyoid bone is the central part of the hyoid bone. *At the fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
