L4 Bone Physiology

Question 1

Discuss the functions of bone?

Answer 1

-support
-protection
-movement
-blood formation

Question 2

When the body produces too much _______, bone can release ______ minerals such as ______ and ______ to neutralize the acid. This process is called __________.

Answer 2

acid
alkaline
calcium
bicarbonate
bone resorption

Question 3

When the blood pH becomes too _____, ______ hormone is released from the parathyroid gland. It travels to the _____ and stimulates ______ ( cells which break down bone ). They release _____ into the bloodstream which helps to raise the blood pH.

Answer 3

acidic
parathyroid
bone
osteoclasts
alkaline minerals

Question 4

Composition of bones are _____ and ____ substances.

Answer 4

65% inorganic - calcium, phosphate
35% organic - collagen, non collagenous protein

Question 5

Osteogenic cells occur in the membranous ____ and ______. They are ____ cells that arise from embryonic _______. They differentiate into ____.

Answer 5

periosteum
endosteum
stem
fibroblast
osteoblasts

Question 6

Osteoblasts are ________ cells that synthesize the ______ matter of the bone matrix and help ______ the bone.

Answer 6

bone-forming
organic
mineralize

Question 7

Osteocytes are former ____ that have become ____ in the matrix they deposited. The processes of neighbouring osteocytes are joined by _______ which allow nutrients to be passed to each other.

Answer 7

osteoblasts
trapped
gap junctions

Question 8

Osteoclasts are ________ cells found on the _____ surface. They develop from the same ______ cells that produce monocytes of the blood.

Answer 8

bone-dissolving
bone
bone marrow

Question 9

Osteoclasts causes bone ____ by secreting _______ which degrades the organic matrix. The chemicals secreted make the environment _____ that enhances the _____ of bone minerals.

Answer 9

resorption
proteolytic enzymes
acidic
solubility

Question 10

Bones replace existing CT in 2 ways which are?

Answer 10

-as intermembranous bones
-as endochondral bones

Question 10

Intramembranous ossification is where bone forms _____ from the ______ CT.

Answer 10

directly
mesenchymal

Question 10

Endochondral ossification is where bone forms by ________ ______ cartilage.

Answer 10

replacing
hyaline

Question 10

Bone resorption is by the action of _____ and _____.

Answer 10

osteoclasts
PTH

Question 11

Bone deposition is by the actions of _____ and ____.

Answer 11

osteoblasts
calcitonin

Question 12

PTH is produced in response to a ____ in blood _____ ions that will cause an elevation in the amount of calcium in the body.

Answer 12

drop
calcium

Question 13

PTH will elevate amount of calcium in body in 3 ways which are?

Answer 13

• increase osteoclast number and activity, increases bone resorption

-decrease calcium excretion by kidney, increase phosphate excretion

-increase calcitriol synthesis from vitamin D

Question 14

Calcitriol ____ plasma ____ levels by stimulating calcium _____ from the _______ and calcium _____ in the _____ of the kidneys.

Answer 14

increase
calcium
absorption
digestive tract
reabsorption
distal tubules

Question 15

Calcitonin is produced in response to a ____ in blood ____ ions that will cause a ____ in the amount of calcium in the body.

Answer 15

rise
calcium
decrease

Question 16

Calcitonin will decrease the amount of calcium in the body by ?

Answer 16

inhibiting osteoclast activity, decreasing bone resorption, increases bone mineralization