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There are regulatory mechanisms which maintain calcium homeostasis:
 
There are regulatory mechanisms which maintain calcium homeostasis:
 
#Buffering - exchangeable calcium is present in bone salts - amorphous calcium phosphate (CaHPO4) is in a state of reversible equilibrium with calcium and phosphorous in extracellular fluid. Exchangeable calcium is alsp present in mitochondria.
 
#Buffering - exchangeable calcium is present in bone salts - amorphous calcium phosphate (CaHPO4) is in a state of reversible equilibrium with calcium and phosphorous in extracellular fluid. Exchangeable calcium is alsp present in mitochondria.
#Hormonal regulation - calcium levels in the body are regulated by hormones produced in the [[Parathyroid Glands - Anatomy & Physiology|Parathyroid Glands]], the C-Cells (also called parafollicular cells) of the [[Thyroid Gland - Anatomy & Physiology|Thyroid Gland]] and the kidneys.
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#Hormonal regulation - calcium levels in the body are regulated by hormones produced in the [[Parathyroid Glands - Anatomy & Physiology|Parathyroid Glands]], the C-Cells (also called parafollicular cells) of the [[Thyroid Gland - Anatomy & Physiology|Thyroid Gland]] and the kidneys:
#Chief cells, also known as ''Principal Cells'', of the parathyroid gland secrete '''Parathyroid Hormone''' (PTH) which '''INCREASES''' calcium levels in the blood.
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#*Chief cells, also known as ''Principal Cells'', of the parathyroid gland secrete '''Parathyroid Hormone''' (PTH) which '''INCREASES''' calcium levels in the blood.
#The kidneys activate Vitamin D3 to create '''Active Vitamin D3''' also known as '''Calcitriol''' to '''INCREASE''' calcium levels in the blood.
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#*The kidneys activate Vitamin D3 to create '''Active Vitamin D3''' also known as '''Calcitriol''' to '''INCREASE''' calcium levels in the blood.
#C-Cells of the thyroid gland secrete '''Calcitonin''' which '''DECREASES''' calcium levels in the blood.
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#*C-Cells of the thyroid gland secrete '''Calcitonin''' which '''DECREASES''' calcium levels in the blood.
     
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