Nutrition Final Ch 9

The primary active form of vitamin D in the body.

calcitriol

Trabecular

Bone fractures caused by aging are usually found in this type of bone.

40 years

By this age bone resorption outpaces bone formation.

Osteomalacia

In adults a long-term vitamin D deficiency results in this condition.

Kidney

Magnesium deficiencies disrupt mineral retention by this organ.

A comparison of an individual's bone density to the average peak bone density of a 30-year-old healthy adult.

T-score

Calcitonin

This hormone inhibits absorption of calcium by the kidneys and intestine.

Bone remodeling

This is a two-step process through which bone is recycled.

Oxalate

This is substance found in plant foods binds dietary calcium making it less available for absorption into the body.

Calcitrol

This is the active form of vitamin D.

500 mg

This is the maximum amount of calcium that can be absorbed into the body at one time.

Calcium

This is the most abundant mineral in the body.

Trabecular

This is the spongy bone found at the end of long bones.

Phosphorous

This mineral combines with calcium to form hydroxyaptite crystals that make bones hard.

magnesium

This mineral is a cofactor in an enzyme system involved in the production of ATP.

Collagen

This organic substance give bones their flexibility.

Vitamin K

This vitamin is a coenzyme in the regulation of blood coagulation.

Vitamin D

This vitamin regulates calcium absorption and utilization.

Fluoride

Too much of this mineral increases the protein content of teeth causing discoloration and pits.

...

Vitamin K is involved in the synthesis of this protein involved in bone turnover.

Northern most point at which adequate vitamin D synthesis is possible

What is the vitamin D insufficiency line?

PTH

When blood calcium levels fall, this hormone stimulates osteoblasts to breakdown bones and release calcium.

The degree to which our body can absorb and utilize any given nutrient.

bioavailability

The degree of compactness of bone tissue, reflecting the strength of the bones. Peak is when it's at it's strongest.

bone density

A hormone secreted by the thyroid gland when blood calcium levels are too high. Inhibits the actions of vitamin D, preventing reabsorption of calcium in the kidneys, limiting calcium absorption in the small intestine, and inhibiting the osteoclasts from breaking down bone.

calcitronin

A failure of muscles to relax, which leads to a hardening or stiffening of the muscles; caused by high levels of blood calcium.

calcium rigor

A condition in which muscles experience twitching and spasms as a result of inadequate blood calcium levels.

calcium tetany

A protein that forms strong fibers in bone and connective tissue.

collagen

A dense bone tissue that makes up the outer surface of all bones as well as the entirety of most small bones of the body.

cortical bone (compact bone)

Currently, the most accurate tool for measuring bone density.

dual energy x-ray absorptiometry (DXA or DEXA)

A condition marked by staining and pitting of the teeth; caused by an abnormally high intake of fluoride.

fluorosis

A condition marked by an abnormally high concentration of calcium in the blood.

hypercalcemia

A condition marked by an abnormally high concentration of magnesium in the blood.

hypermagnesemia

A condition characterized by an abnormally low concentration of calcium in the blood.

hypocalcemia

A condition characterized by an abnormally low concentration of magnesium in the blood.

hypomagnesemia

Cells that prompt the formation of new bone matrix by laying down the collagen-containing component of bone, which is then mineralized.

osteoblasts

Cells that erode the surface of bones by secreting enzymes and acids that dig grooves into the bone matrix.

osteoclasts

A vitamin D-deficiency disease in adults, in which bones become weak and prone to fractures.

osteomalacia

A disease characterized by low bone mass and deterioration of bone tissue, leading to increased bone fragility and fracture risk.

osteoporosis

A hormone secreted by the parathyroid gland when blood calcium levels fall. It increases blood calcium levels by stimulating the activation of vitamin D, increasing reabsorption of calcium from the kidneys, and stimulating osteoclasts to break down bone, which releases more calcium into the bloodstream.

parathyroid hormone (PTH)

The two-step process by which bone tissue is recycled; includes the breakdown of existing bone and the formation of new bone.

remodeling

The process by which the surface of bone is broken down by cells called osteoclasts.

resorption

A vitamin D-deficiency disease in children. Signs include deformities of the skeleton, such as bowed legs and knocked knees. Can be fatal.

rickets

A porous bone tissue that makes up only 20% or our skeleton and is found within the ends of the long bones, inside the spinal vertebrae, inside the flat bones (sternum, ribs, and most bones of the skull), and inside the bones of the pelvis.

trabecular bone (spongy bone)