Bio 201
Question 1
Match the items with the descriptions. You will repeat some choices.
The action potential runs along this part of the muscle fiber.
Calcium voltage-gated channels and calcium pumps are both abundant in this membrane.
Repeating contractile units are assembled in a chain in the muscle fiber called this.
Calcium has to interact with this in order to enable contraction to occur.
This has to be moved to uncover the myosin-binding sites on actin filaments.
This membrane does not carry an action potential but it does sense the nearby action potential.
This undergoes a conformational change when it associates with calcium.
Mitochondria are found in this region of the muscle fiber.
Myosin contributes to making this.
t-tubules are a part of this.
All Answer Choices
A. tropomyosin
B. sarcoplasm
C. sarcoplasmic reticulum
D. troponin
E. myofibril
F. sarcolemma
Question 2
Match each statement with whether it has to do with the actin filament or the myosin filament.
This filament makes cross-bridges during contraction.
This filament primarily makes up the A band of the sarcomere. myosin filament
This filament is composed of globular proteins.
ATP binds to the proteins on this filament.
This filament is wrapped by tropomyosin.
All Answer Choices
A. myosin filament
B. actin filament
Question 3
How does this item relate to the thick filament?
Answer Choices
ten of these make up a thick filament
two of these make up a thick filament
thousands or more of these make up a thick filament
this is the same thing as a thick filament
it doesn’t relate to a thick filament because it is found in a thin filament
Question 4
This would be the A band.
This is one actin filament.
Myosin filaments align with one another along this line.
This band close to the Z line gets smaller during contraction.
This band close to the M line gets smaller during contraction. 2
This is one sarcomere.
This site is where ATP would bind.
Tropomyosin, but no myosin, would be found in this region.
All Answer Choices
A. 6
B. 8
C. 1
D. 3
E. 5
F. 4
G. 7
H. 2
Question 5
A sarcomere spans from [1] to [2]. Actin filaments, but not myosin filaments, are found in the [3]. The zone of overlap between actin and myosin filaments is part of the [4]. The myosin filaments are all held in position at the [5]. When contraction occurs, the [6] (located more centrally within the sarcomere) and the [7] (located more laterally within the sarcomere) get smaller. The actin filaments are held in position at the [8].
All Answer Choices
A band
I band
M line
Z line
H zone
Question 6
This question is about the contractile machinery in a muscle fiber. An answer may be used more than once or not at all.
The basic unit for contraction within a skeletal muscle fiber is the sarcomere. When these basic units are stuck end-to-end into a long chain that runs along the long axis of the entire muscle fiber they make up the [2]. For contraction you need both thick filaments and thin filaments. The thin filaments are the [3] filaments.The filaments containing the proteins that undergo the conformational changes needed to contract are the [4] filaments. There are both dark and light bands that make up the striations of a muscle fiber. The filaments that give rise to the dark bands of the striations are the [5] filaments. These dark bands are called [6] bands. The thin filaments are all attached to the [7] lines, which demarcate the ends of the basic contractile unit. When a muscle fiber contracts, the [8] bands shrink but the [9] bands do not change length. The t-tubules run along the [10] lines to bring the electrical signal close to every bit of contractile machinery within a muscle fiber.
All Answer Choices
pick one:
actin
myosin
myofibril
muscle fiber
sarcomere
A
I
M
Z
