Muscular and skeletal systems

Question 1

what do chondrocytes do

Answer 1

synthesize cartilage

Question 2

describe compact bone

Answer 2

• dense bone that makes up 80% of skeleton

- bony matrix deposited in osteons

Question 3

describe an osteon

Answer 3

consists of a central microscopic channel called a Haversian canal surrounded by concentric circles of bony matrix called lamellae

Question 4

where is spongy bone found

Answer 4

ends of long bones, in pelvic bones, skull, and vertebra

Question 5

describe spongy bone

Answer 5

much less sense and consists of interconnecting lattice of bony spicules (trabeculae)

Question 6

what do the cavities between the spicules consist of

Answer 6

yellow or red bone marrow

Question 7

what is yellow marrow made of

Answer 7

adipose tissue

Question 8

what is red marrow involved in

Answer 8

blood cell formation

Question 9

what happens in endochondral ossification

Answer 9

existing cartilage is replaced by bone

Question 10

what do long bones arise from

Answer 10

endochondral ossification

Question 11

what happens in intramembranous ossification

Answer 11

mesenchymal connective tissue is transformed into and replaced by bone

Question 12

what are myofibrils enveloped by

Answer 12

sarcoplasmic reticulum

Question 13

what happens in a muscle cell when an action potential is generated

Answer 13

calcium ions are released

Question 14

what does calcium bind to

Answer 14

troponin on the actin filaments, which causes myosin to bind

Question 15

what is the latent period

Answer 15

the time between stimulation and the onset of contraction

Question 16

what happens during the latent period

Answer 16

the action potential spreads along the sarcolemma and calcium is released

Question 17

what absolute refractory period

Answer 17

the period of time after a contraction where a muscle is unresponsive to a stimulus