Parathyroid Gland Flashcards
The parathyroid glands are _____ , _____ glands that produce ______
Small
Endocrine
Parathyroid hormone(PTH)
Parathyroid gland is about the size of _____ and is _____ in colour.
Rice grain
Yellowish brown
Dimension of the parathyroid gland:
Length: ___
Width: ____
Thickness: ____
Length:6mm
Width:4mm
Thickness: 2mm
The parathyroid glands usually weighs between ____ - ____ in humans
25mg-50mg
The parathyroid gland is located on the _______ surface of the thyroid gland
N/B: Sometimes, parathyroid gland is located within(rare cases) the thyroid gland.
Posterior
The parathyroid glands are named for their ______ to the thyroid gland but serve a completely _____ role than the thyroid gland.
Proximity
Different
Parathyroid glands are normally ____ in number; positioned higher are called the ______ while the lower two are called the _____. Occasionally, some individuals may have ___ , ___ or even more.
Four
Superior parathyroid glands
Inferior parathyroid glands
Six, eight
The major function of the parathyroid gland is to ______ through the secretion of ______
Maintain the body’s calcium levels
Parathyroid hormones
When blood calcium levels drop below a certain point, _______ in the parathyroid gland are activated to release hormone into the blood to increase calcium level .
Therefore, PTH opposes the function of ______ produced by the thyroid gland
calcium-sensing receptors
Calcitonin
Action of parathyroid hormone:
Bone: stimulate osteoclasts activity
GIT: stimulates the activation of vitamin D
Kidney: stimulate Ca2+ absorption
The parathyroid gland is an ____ structure seen ____ the thyroid gland.
Oval
Behind
Histology:
Microscopically, the parathyroid glands consist ________ columns of cells supported by _______ containing rich supply of ________
Intercommunicating
Connective tissue
Blood capillaries
Histology:
Microscopically, the parathyroid glands consist ________ columns of cells supported by _______ containing rich supply of ________
Intercommunicating
Connective tissue
Blood capillaries
Parathyroid glands are made up of ___ kind of cells, namely:
Two
Principal/chief cells
Oxyphil cells
Describe the blood supply of parathyroid gland.
The blood supply of the parathyroid gland is from the thyroid gland.
Superior parathyroid glands get blood supply from _____ and the inferior parathyroid glands get blood supply from ______
Superior parathyroid artery which arises from anastomoses network of the superior and inferior thyroid arteries
Inferior parathyroid artery which arises from the inferior thyroid artery
Innervation of parathyroid gland is by _____.
Autonomic Nervous System
Sympathetic innervation of parathyroid glands:
Superior Sympathetic Cervical Ganglion
Middle Sympathetic Cervical Ganglion
Parasympathetic innervation of the parathyroid gland:
Vagus Nerve
Hyperparathyroidism causes _____ of the parathyroid hormone(due to ______) high can lead to _____ which can lead to :
Over secretion
Tumor of the parathyroid gland
Hypercalcemia
Kidney stones
Osteoporosis
Atrial Fibrillation
Hypoparathyroidism is ______/______ and causes ______ of parathyroid hormone which leads to _____
Rare/ uncommon
Undersecretion
Low Ca2+ level
