Thyroid Flashcards
(63 cards)
When does the thyroid gland begin to develop during human embryo formation?
Around the 4th week of gestation.
Where does the thyroid gland initially develop?
At the floor of the primitive pharynx, just below the base of the tongue.
What is the thyroid gland’s initial form during early development?
A small endodermal diverticulum.
During which weeks of fetal development does the thyroid migrate downward?
7th to 8th week.
What is the final position of the thyroid gland after migration?
Anteriorly to the trachea.
What structure connects the two lobes of the thyroid gland?
The isthmus.
Common ectopic sites for thyroid tissue include _______.
- Lingual Thyroid
- Mediastinal Thyroid
- Prelaryngeal Thyroid
Where is the thyroid gland located in the body?
In the anteroinferior neck, just below the thyroid cartilage.
What is the characteristic shape of the thyroid gland?
Butterfly shape.
What are the dimensions of an adult thyroid lobe?
- Length: 40–60 mm
- Anteroposterior diameter: 20–30 mm
- Width: 15–20 mm
What arteries supply the thyroid gland?
- Superior thyroid arteries
- Inferior thyroid arteries
What is the primary function of the thyroid gland?
Regulating metabolism by producing T3 and T4 hormones.
What hormones are primarily produced by the thyroid gland?
- Triiodothyronine (T₃)
- Thyroxine (T₄)
- Calcitonin
What is the role of calcitonin?
Helps lower blood calcium levels.
What is hypothyroidism?
A condition where the thyroid produces insufficient amounts of thyroid hormones.
Common causes of hypothyroidism include _______.
- Hashimoto’s Thyroiditis
- Iodine deficiency
- Thyroidectomy
- Radioactive iodine treatment
Symptoms of hypothyroidism include _______.
- Weight gain
- Fatigue
- Cold intolerance
- Constipation
What is hyperthyroidism?
A condition where the thyroid gland produces excessive amounts of thyroid hormones.
Common causes of hyperthyroidism include _______.
- Graves’ Disease
- Toxic nodules
Symptoms of hyperthyroidism include _______.
- Weight loss
- Increased appetite
- Heat intolerance
- Sweating
What does a TSH test measure?
The level of TSH in the blood.
What does a high TSH level indicate?
Hypothyroidism.
What is the normal range for TSH?
0.4 - 4.0 mIU/L.
What does the free T₃ and T₄ test measure?
Levels of active thyroid hormones circulating in the blood.