Thyroid Gland Flashcards
Thyroid gland is where and what
Largest pure endocrine gland, located in front of the neck
What is the thyroid gland composed of
Follicles
What are the follicles lined by
single layer of epithelial cube shaped cells
What is between the follicles
Connective tissue that contains parafollicular cells
What two hormones are produced by TG
Thyroid Hormone and Calcitonin
Thyroid Hormone
1) What is it produced and stored by
2) Effects mainly what
3) Promotes what
4) What two sub hormones is it composed of
5) What is the major sub hormone
6) Where is the minor sub hormone produced
7) What is the main difference between the 2 sub hormones
1) Thyroid follicles
2) Metabolism
3) Growth
4) thyroxine (T4) and triiodothyronine (T3)
5) T4
6) Target tissues by conversion of T4 to T3
7) T4 has 4 iodine while T3 has 3
Calcitonin
1) Produced by
2) What does it lower
3) What does it promote
4) What is its release controlled by
1) Parafollicular cells
2) Calcium ion level in blood
3) Bone formation by stimulating osteoblasts
4) Level of calcium ions in blood
What is hyperthyroidism
Increased levels of thyroid hormone
Hyperthyroidism causes what
Graves Disease/Thyrotoxicosis
Manifestations of Graves disease
increased metabolic rate, profuse sweating, increased heart rate, nervous agitation, exophthalmos (bulging eyes)
Hypothyroidism causes what
Cretinism in children or myxoedema in adults
Manifestations of Hypo
Low metabolic rate, lethargy, mental sluggishness and poor concentration, puffy skin around eyes and swollen limbs due to fluid accumulation and dry thick skin
