Calcium & Phosphate in Body Regulation

Vocabulary flashcards created to help review key concepts related to calcium and phosphate regulation in the body.

Calcium (Ca2+)

A vital mineral that plays critical roles in bone structure, muscle function, and cellular processes.

Inorganic Phosphate (Pi)

A key component in bone mineralization and energy metabolism, represented as H2PO4^- and HPO4^{2-} in plasma.

Homeostasis

The regulation of physiological processes to maintain stable internal conditions, including calcium and phosphate levels.

Osteoclasts

Cells responsible for the resorption of bone, breaking down bone tissue and releasing calcium and phosphate into the bloodstream.

Osteoblasts

Cells that form new bone, synthesizing bone matrix and mineralizing it to increase bone density.

Parathyroid hormone (PTH)

A hormone that regulates calcium levels in the blood, increasing osteoclast activity and calcium reabsorption in kidneys.

Calcitriol (1,25(OH)2D3)

The active form of Vitamin D that facilitates calcium absorption in the intestine and helps maintain calcium homeostasis.

Calbindin

A calcium-binding protein that aids in the transport of calcium in the intestinal cells.

FGF23

Fibroblast Growth Factor 23, a hormone that regulates phosphate metabolism and is involved in calcium homeostasis.

Osteoporosis

A condition characterized by weak and brittle bones, often occurring in post-menopausal women due to decreased estrogen levels.

Hormonal regulation of calcium balance

The interaction of hormones like PTH, Vitamin D, and Calcitonin in maintaining blood calcium levels.

Negative calcium balance

A condition where calcium absorption is less than calcium excretion, potentially leading to bone loss.

Positive calcium balance

A condition where calcium absorption exceeds calcium excretion, contributing to bone formation.

Renal handling of minerals

The process by which the kidneys regulate the excretion and reabsorption of minerals like calcium, phosphate, and magnesium.

Estrogens

Hormones that play a crucial role in bone maintenance and help prevent osteoporosis by regulating osteoblast and osteoclast activity.

Calcitonin

A hormone that lowers blood calcium levels by inhibiting osteoclast activity and promoting calcium deposition in bones.