Skeletal Muscle Physiology 1

Question 1

name the 3 types of muscle in the body

Answer 1

skeletal
cardiac
smooth

Question 2

which 2 muscle types are striated?

Answer 2

skeletal and cardiac

Question 3

what causes the dark bands in muscle under a microscope?

Answer 3

thick myosin filaments

Question 4

what causes the light bands in muscle under a microscope?

Answer 4

thin actin filaments

Question 5

what muscle type does not have striation?

Answer 5

smooth muscle

Question 6

skeletal muscle are innervated by _______ nervous system so are _________ wheres cardiac and smooth are innervated by the ___ and are so ___________

Answer 6

skeletal muscle are innervated by somatic nervous system so are voluntary wheres cardiac and smooth are innervated by the ANS and are so involuntary

Question 7

in which muscle type are there neuromuscular junctions present?

Answer 7

skeletal

Question 8

are gap junctions present in skeletal muscle?

Answer 8

no - only in cardiac muscle

Question 9

excitation contraction of skeletal muscle is due to what? from where?

Answer 9

Ca2+ from sarcoplasmic reticulum

Question 10

name the chemical transmitter at the neuromuscular junction

Answer 10

acetylcholine

Question 11

define the motor unit

Answer 11

a single alpha motor neuron and all the skeletal muscle fibres it innervates

Question 12

muscles which serve fine movements have _____ fibres per motor unit

Answer 12

fewer

Question 13

muscle fibre > _________ > sarcomere > myosin and _____

Answer 13

muscle fibre > myofibril > sarcomere > myosin and actin

Question 14

each muscle fibre contain many what?

Answer 14

myofibrils

Question 15

actin and myosin are arranged into what?

Answer 15

sarcomeres - the functional units of muscle

Question 16

define the functional unit

Answer 16

the smallest component capable of performing all the functions of that organ

Question 17

the sarcomere is found between 2 what?

Answer 17

Z lines

Question 18

name the 4 comes of the sarcomere

Answer 18

A-band
H-zone
M-line
I-band

Question 19

the A-band is…

Answer 19

Made up of thick filaments along with portions of thin filaments that overlap in both ends of thick filaments

Question 20

the H-zone is…

Answer 20

Lighter area within middle of A-band where thin filaments don’t reach

Question 21

the M-line…

Answer 21

Extends vertically down middle of A-band within the centre of H-zone

Question 22

the I band…

Answer 22

Consists of remaining portion of thin filaments that do not project in A-band

Question 23

the force generation in muscle depends upon what?

Answer 23

ATP-dependent interaction

Question 24

ATP is required for both contraction & relaxation

true or false?

Answer 24

true

Question 25

In skeletal muscle fibres, Ca2+ is released from the lateral sacs of the sarcoplasmic reticulum when the surface action
potential spreads down
the __________ _ _______

Answer 25

transverse (T)-tubules

Question 26

what is required to switch on cross bridge formation?

Answer 26

Ca2+

Question 27

the muscle fibre is relaxed when the binding site is physically covered by the what?

Answer 27

troponin-

tropomyosin complex

Question 28

the muscle fibre becomes excited when Ca2+ binds with what?

Answer 28

troponin

Question 29

the thin filament is pulled inward during contraction

true or false?

Answer 29

true

Question 30

What’s the difference between Luiseach Mathers and a vampire?

source: http://www.jokes4us.com/dirtyjokes/gingerjokes.html

Answer 30

One is a pale, bloodsucking creature that avoids the sun. The other is a vampire.