Chapter 11 Lecture Flashcards
List the nutrients involved in bone health
Calcium, vitamins A & D, fluoride, vitamin k, phosphorus, magnesium
During resorption, the surface of bones is broken down by ___________
Osteoclasts
Define osteoblasts
Bone-building cells that produce the collagen-containing component of bone that is mineralized
Define osteoclasts
Bone-resorbing cells release acid and enzymes to dissolve bone/erode the surface of bones
Define bone mineral density
Total mineral content of bone at a specific bone site divided by width of bone at site
Bone is composed of what percentage of minerals?
65%
Bone is composed of what percent of connective tissue?
35%
Peak bone mass is achieved by age ___
30
Bone resorption occurs at a rate faster than bone synthesis after age ___
30
Density engines to decrease after age ___ because resorption exceeds new bone formation
40
Which sex has lower bone mass and density?
Women
Calcium is what percentage of all minerals in body?
40%
List functions of calcium
Blood clot formation, muscle contraction, nerve transmission, cellular metabolism, enzymes, hormonal responses, maintaining cell integrity, promoting cell differentiation
What is the RDA of calcium per day for adults up to 50 years old?
1000 mg per day
What is the average US intake of calcium per day for women?
800 mg
What are the 3 best sources of dairy?
Milk, yogurt, cheese
What provides 75% of the calcium in North American diets?
Dairy products
Vitamin D activation occurs in _______ and kidneys
Liver
Vitamin D increases calcium absorption in the ______ intestine
Small
Vitamin D maintains _____ and phosphorus levels in blood
Calcium
Vitamin D binds to and affects cells of which systems/organs?
Immune system, brain and nervous system, skin, muscles, reproductive organs
