Calcium and Bone

Question 1

Calcium

Answer 1

Important for bone, nerve and muscle function, and as a second messenger in all cells

Question 2

Bone

Answer 2

Reservoir for calcium and houses marrow, consists of bone cells, CaPO4, reinforcing collagen fibers and other proteins

Question 3

Bone Marrow

Answer 3

Produces blood and stores fat, found in trabecular zone and hollow core

Question 4

Bone has outer ____ and inner ______

Answer 4

Outer cortical and inner trabecular zones

Question 5

Osteoblasts

Answer 5

Bone building cells

Question 6

Osteoclasts

Answer 6

Bone dissolving cells

Question 7

What influences activity of bone cells?

Answer 7

Hormones and mechanical stress

Question 8

What 3 hormones control calcium levels

Answer 8

PTH, Calcitriol and Calcitonin

Question 9

PTH

Answer 9

Parathyroid hormone, increases calcium levels, stimulates osteoclasts to dissolve bone and release calcium, stimulates kidney to reabsorb more calcium using calcium pumps

Question 10

Calcitriol

Answer 10

Activated vitamin D, activated by the kidney and liver, causes small intestine to absorb more calcium

Question 11

Inactive Vitamin D

Answer 11

Skin makes it, it is also found in milk

Question 12

Calcitonin

Answer 12

From thyroid gland, inhibits osteoclast activity, may be important in pregnancy and lactation to protect mom from bone thinning