M7S3: The Thyroid Gland

Question 1

Thyroid gland overview

Answer 1

-sits in the neck anterior to trachea and inferior to larynx
-important structure in maintaining metabolic homeostasis

Question 2

Lobes of thyroid gland

Answer 2

3 anatomical structures: right lobe, left lobe, and isthmus (which sits in between and connects the 2 lobes)
*refer to goodnotes

Question 3

Lobes of thyroid gland

Answer 3

3 anatomical structures: right lobe, left lobe and the isthmus (which sits in between and connects the two lobes)

Question 4

Histology of Thyroid Gland

Answer 4

-composed of many structures called follicles
-each follicle lined with simple cuboidal follicular cells that surround a central lumen filled with material called colloid (a protein rich fluid secreted by the follicular cells of thyroid gland)
-dispersed between the follicles are parafollicular or ‘C’ cells
-think of thyroid glands as being bag of tennis balls, where gland itself the bag and the follicles are the tennis balls
*refer to goodnotes

Question 5

Cells of thyroid gland

Answer 5

-each cell secretes specific hour,ones
-hormones play role in regulating different body functions

Follicular cells
-simple cuboidal cells that surround each follicle
-cells produce Triiodothyronine (T3) and Thyroxine (T4), which act to increase rate of metabolism and oxygen consumption

C cells
-important in calcium homeostasis
-produce calcitonin, hormone which lowers blood concentration
*refer to goodnotes

Question 6

Goitre condition

Answer 6

-phsyiological condition where thyroid gland expands it size, causing lump on neck
-can be caused by excess or lack of thyroid hormone T3 and T4
-TSH pituitary gland results in higher T3 and T4 levels when in excess

Treatment:
-depends on severity
-some cases = no treatment
Other cases = thyroid hormone replacement drug or surgery to remove the goitre
*refer to goodnotes images