Chapter 12 (Part 1)

Question 1

skeletal muscle is composed of ?

Answer 1

bundles of muscle fibers called fascicles

Question 2

what is the name of the membrane around muscle fiber

Answer 2

sarcolemma

Question 3

sarcolemma

Answer 3

name of the membrane around muscle fiber

Question 4

what happens to muscle cells that don’t fuse to form a fiber and are able to divide?

Answer 4

either self-renew, or differentiate into cardiomyocytes, smooth muscle cells or endothelial cells

Question 5

what makes up a muscle fiber?

Answer 5

fused muscle cells

Question 6

what is a muscle fiber filled with?

Answer 6

myofibrils

Question 7

what surrounds a myofibril?

Answer 7

SR: sarcoplasmic reticulum

Question 8

each myofibril contains bundles of _______ connected together inside the fiber

Answer 8

sarcomeres

Question 9

where are myofibrils found?

Answer 9

muscle fiber is filled with myofibrils

Question 10

where is the SR located?

Answer 10

surrounds each myofibril

Question 11

where are sarcomeres located?

Answer 11

connected together inside the myofibril

Question 12

what is the contractile unit of the muscle

Answer 12

sarcomere

Question 13

what wraps around each SR?

Answer 13

transverse tubules

Question 14

where are transverse tubules located?

Answer 14

wrapped around the SR that surround each myofibril

Question 15

as the AP moves along the ______ ….

Answer 15

T tubules, it triggers Ca+2 release from the SR onto sarcomeres within the myofibrils

Question 16

where is Ca+2 released from? what triggers its release?

Answer 16

released from SR

triggered by AP moving along the T tubules

Question 17

what are thin filaments made of?

Answer 17

actin

Question 18

what are thick filaments made of?

Answer 18

myosin

Question 19

what attaches myosin to the Z line

Answer 19

the protein titin

Question 20

what is the role of the protein titin

Answer 20

attach thick filaments to the Z line