Calcium Storage and Metabolic Regulation

These flashcards cover key vocabulary and concepts related to calcium storage, hormonal regulation, bone remodeling, and the physiological significance of calcium in the body.

Parathyroid Hormone (PTH)

A hormone secreted by the parathyroid glands that increases blood calcium levels by promoting resorption of calcium from bones and increasing calcium reabsorption in the kidneys.

Calcitonin

A hormone produced by the thyroid that lowers blood calcium levels by inhibiting osteoclast activity in the bones.

Calcium sensing receptor (CaSR)

A receptor that helps regulate calcium levels in the blood by influencing the secretion of parathyroid hormone.

Vitamin D

A fat-soluble vitamin that is important for calcium absorption in the intestines and is activated in the kidneys.

Bone Remodeling

The process by which bone tissue is continuously renewed through the action of osteoclasts (which break down bone) and osteoblasts (which build up bone).

Osteoblasts

Bone cells responsible for bone formation and the production of the bone matrix.

Osteoclasts

Bone cells that break down bone tissue during the process of bone resorption.

Bone Mass

The amount of bone tissue in the skeleton, which can be influenced by factors like age, diet, and physical activity.

Hyperparathyroidism

A condition caused by excessive parathyroid hormone which leads to increased blood calcium levels and can result in osteoporosis.

Hypoparathyroidism

A condition resulting from insufficient parathyroid hormone, leading to low blood calcium levels.

Biodistribution of Calcium

The distribution of calcium in the body, with approximately 99% found in bones and only about 1% in plasma.

Calcium Intake Recommendations

Daily calcium intake recommendations vary by age and physiological status, such as 600 mg/day for children and 1300 mg/day for adolescents.

Wolff's Law

The principle that bone adapts to the loads under which it is placed; increased physical load leads to increased bone density.

Osteoporosis

A condition characterized by decreased bone density and increased fracture risk, often occurring in postmenopausal women.

Calcium Absorption Efficiency

The effectiveness with which the body can absorb calcium from dietary sources, which tends to decline with age.

Bone-Lining Cells

Cells that line the surface of bones and play a role in the maintenance and remodeling of bone tissue.

Nerve Conduction

The process by which nerves transmit signals, which requires calcium for neurotransmitter release and muscle contraction.