Lecture 27 - Endocrine Flashcards
Thyroid (Write it out)
Location:
Structure:
Blood Supply:
Blood Drainage:
Thyroid (Write it out)
Location:
- anterior, below thyroid cartilage
- inf larynx
Structure:
- 2 lobes connected via isthmus
Blood Supply:
- Superior thyroid artery
= branch of external carotid artery
- Inferior thyroid artery
= branch of the subclavian arteries
Blood Drainage:
- Superior and middle thyroid veins
= drain into internal jugular vein
- Inferior thyroid vein
= drains into the brachiocephalic vein
- collectively veins drain into the superior vena cava
Where do veins of the thyroid collectively drain>
Superior vena cava
Where does the the superior thyroid artery branch from
Superior thyroid artery = branch of the external carotid artery
Where does the inferior artery branch from>
Inferior thyroid artery = branch of the subclavian artery
Where do the superior and middle thyroid veins drain into?
The Superior and middle thyroid veins drain into the internal jugular vein
Where do the inferior thyroid veins drain into?
The inferior thyroid veins into the brachiocephalic vein
What cells make up the thyroid – type
Simple cuboidal cells called follicular cells make up the thyroid
What is stored in the cavity of follicular cells in the thyroid - describe
Colloid
- consists of thyroglobin
- contains molecules of tyrosine which get converted to thyroid hormone by iodine
What do follicular cells produce?
Follicular cells produce thyroglobulin
What are the names of T3 and T4?
T3 = Triiodothyronine
T4 = Thyroxine
What produces T3 and T4?
T thyrocytes produce T3 and T4
What stims release of T3 and T4?
TSH from the ant pit
Describe what happens when TSH is released
- TSH released from ant pit
- cuboidal cells take a bite of the colloid and ingests material
- inside the colloid there areT3 and T4 and enzymes help to get them out
What are the functions of thyroid hormones?
1) Increase rate of cellular metabolism and oxygen consumption
2) Helps maintain bp
3) Plays a role in tissue growth and development
What’s large parafollicular c cells or follicular cells
parafollicular cells