Thyroid Flashcards
– butterfly shaped, 2 lobes separated by Isthmus and straddles the trachea
Thyroid gland
Largest endocrine gland
Thyroid gland; (15-25g)
enumerate the principal cells of the thyroid gland
- Follicular epithelium; T3, T4
- Parafollicular cells: Calcitonin
What is the main function of the Thyroid gland?
produce thyroid hormones. Iodine storage
GIve the normal Thyroid iodide to plasma iodide ratio:
25-40:1
TRUE or FALSE: Iodine is needed for hormone synthesis
TRUE
Intake for Iodine:
normal intake -
hormone secretion deficiency -
- 1mg/week (150ug/day)
- <50ug/day
Enumerate the 3 components of the thyroid gland
- Follicles
- Colloid
- Thyroglobulin
Responsible for absorbing iodine (ring shape)
Follicles
Reservoir of materials for hormone production surrounded by follicle
Colloid
TRUE or FALSE: Colloid is rich in glycoprotein thyroglobulin
TRUE
this component is with tyrosyl groups (rich in tyrosine)
Thyroglobulin
TRUE or FALSE:
Follicle are the major component of colloid
FALSE; Thyroglobulin are th emajor component of colloid
TRUE or FALSE: Colloid are synthesized and secreted by follicles
FALSE; Thyroglobulin are the ones synthesized and secreted by follicles
which TG component reflects Thyroid mass, injury and TSH receptor stimulation?
Thyroglobulin
TRUE or FALSE: Presence of Thyroglobulin indicate tumor (malignant/benign)
TRUE
Which following conditions does thyroglobulin seen at increased levels?
increase in:
- Graves disease
- thyroiditis
- nodular goiter
The biosynthesis of T3 and T4 is controlled by?
Thyroid Stimulating Hormone (TSH)