PHGY 215 MOD 4 QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW
what are the contractile elements of muscle fibres? Ans✓✓✓ myofibril
what are the functional elements of muscle fibres? Ans✓✓✓ sarcomere
what type of pattern do thick and thin filaments create? Ans✓✓✓
striated
what are the 5 myofibril elements? Ans✓✓✓ A band
H zone
M line
Z line
I band
A-bands:
what are they also called?
what are they made up of? (2)
what are its borders defined by? Ans✓✓✓ dark bands
stacked thick and thin filaments
length of the thick filaments
,I band:
what are they also called?
what are they adjacent to?
what are they made up of? Ans✓✓✓ light band
A band
thin filaments that are not part of the A band
what is the lighter portion of the A band called? Ans✓✓✓ H zone
what is the middle of the I band called? Ans✓✓✓ Z line
H zone:
where is this found?
what is its colour relative to where it is found?
what does the H zone contain?
what do these proteins do?
where in the H zone are these found
which myosin chains does the H zone contain? Ans✓✓✓ in the middle
of the A band
lighter
proteins
hold the thick filaments together
M line
,heavy
what are the two chains that myosin is composed of and how many of
each are there? Ans✓✓✓ 2 heavy
2 light
M line:
what does the m line contain?
where is the M line found? Ans✓✓✓ proteins that hold the thick
filaments together
middle of the H zone
Z line:
where is the Z line found?
what is a sarcomere defined as? Ans✓✓✓ middle of the I band
distance from one Z line to the next
what happens to sarcomere length when the myofibril contracts?
what happens to the myofibril elements? Ans✓✓✓ decreases
move closer together
who do cross bridges form between? Ans✓✓✓ myosin head and actin
, which myofibril element contains sites for cross bridge formation?
where specifically? Ans✓✓✓ a band
where thick and thin filaments overlap
what is the middle of the H zone called? Ans✓✓✓ M line
what protein are the thick filaments composed of? Ans✓✓✓ myosin
what type of protein is myosin?
what does it use to move along the actin filaments? Ans✓✓✓ motor
atp
what type of molecule is myosin? Ans✓✓✓ dimer
what is each subunit of myosin composed of? Ans✓✓✓ globular head
long shaft
within a thick filament, how do the two myosin dimers come together?
Ans✓✓✓ tail to tail
what are the two sites on the myosin heads? Ans✓✓✓ actin binding site
ATPase site
ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED
A+||BRAND NEW
what are the contractile elements of muscle fibres? Ans✓✓✓ myofibril
what are the functional elements of muscle fibres? Ans✓✓✓ sarcomere
what type of pattern do thick and thin filaments create? Ans✓✓✓
striated
what are the 5 myofibril elements? Ans✓✓✓ A band
H zone
M line
Z line
I band
A-bands:
what are they also called?
what are they made up of? (2)
what are its borders defined by? Ans✓✓✓ dark bands
stacked thick and thin filaments
length of the thick filaments
,I band:
what are they also called?
what are they adjacent to?
what are they made up of? Ans✓✓✓ light band
A band
thin filaments that are not part of the A band
what is the lighter portion of the A band called? Ans✓✓✓ H zone
what is the middle of the I band called? Ans✓✓✓ Z line
H zone:
where is this found?
what is its colour relative to where it is found?
what does the H zone contain?
what do these proteins do?
where in the H zone are these found
which myosin chains does the H zone contain? Ans✓✓✓ in the middle
of the A band
lighter
proteins
hold the thick filaments together
M line
,heavy
what are the two chains that myosin is composed of and how many of
each are there? Ans✓✓✓ 2 heavy
2 light
M line:
what does the m line contain?
where is the M line found? Ans✓✓✓ proteins that hold the thick
filaments together
middle of the H zone
Z line:
where is the Z line found?
what is a sarcomere defined as? Ans✓✓✓ middle of the I band
distance from one Z line to the next
what happens to sarcomere length when the myofibril contracts?
what happens to the myofibril elements? Ans✓✓✓ decreases
move closer together
who do cross bridges form between? Ans✓✓✓ myosin head and actin
, which myofibril element contains sites for cross bridge formation?
where specifically? Ans✓✓✓ a band
where thick and thin filaments overlap
what is the middle of the H zone called? Ans✓✓✓ M line
what protein are the thick filaments composed of? Ans✓✓✓ myosin
what type of protein is myosin?
what does it use to move along the actin filaments? Ans✓✓✓ motor
atp
what type of molecule is myosin? Ans✓✓✓ dimer
what is each subunit of myosin composed of? Ans✓✓✓ globular head
long shaft
within a thick filament, how do the two myosin dimers come together?
Ans✓✓✓ tail to tail
what are the two sites on the myosin heads? Ans✓✓✓ actin binding site
ATPase site
