KINE 433 Exam 2 Chapters 1-3 questions with
verified answers
The order of skeletal muscle hierarchical organization, from largest structure to
smallest structure is Ans✓✓ -entire muscle, muscle fiber, fascicle, myofibril
The ______________________ is the basic structure of a myofibril. Ans✓✓ -
sarcomere
Myosin (thick) filament is composed of ________________, while actin (thin)
filament is made of ______________, _________________, and
_______________. Ans✓✓ -myosin; actin; troponin; tropomyosin
The structures that carry action potential deep into all regions of a muscle fiber are
called ______________________. Ans✓✓ -t-tubules
The ________________________ ( a specific region of a myosin molecule) is the
only part of the molecule that will interact with actin to create a cross bridge.
Ans✓✓ -myosin head
Which protein binds to Ca2+ and helps initiate muscle contraction? Ans✓✓ -
troponin
An alpha motor neuron and all the muscle fibers it innervates are collectively
called a(n) ___________________________. Ans✓✓ -motor unit
The series of events that begins with excitation of a motor nerve and results in
muscle contraction is called ________________________. Ans✓✓ -excitation
coupling
, ATP is required for ______________________________. Ans✓✓ -muscle
contraction and muscle relaxation
The theory that states that muscle fibers contract when thin and thick filaments
slide past each other is called the _______________________________ theory.
Ans✓✓ -sliding filament theory
When the myosin head pulls the thin filament toward the center of the sarcomere,
the tilting action of the head is known by this special term:
__________________________. Ans✓✓ -power stroke
Type II fibers have a more highly developed ______________________,
suggesting that type II fibers are more adept at delivering Ca2+ into the muscle cell
during contraction. Ans✓✓ -sarcoplasmic reticulum
Type ______ motor units typically contain fewer muscle fibers, meaning that the
force of contraction from this type of motor unit will be
________________________. Ans✓✓ -1, weaker
Type ______ motor units typically engaged for long periods of low-intensity
aerobic exercise. Type ____ fibers are typically engaged during short, higher
intensity exercise and explosive activities. Ans✓✓ -1, 2
The notion that motor units are usually recruited in a fixed, unvarying order to
produce a given force is called the __________________________________.
Ans✓✓ -orderly recruitment principle
verified answers
The order of skeletal muscle hierarchical organization, from largest structure to
smallest structure is Ans✓✓ -entire muscle, muscle fiber, fascicle, myofibril
The ______________________ is the basic structure of a myofibril. Ans✓✓ -
sarcomere
Myosin (thick) filament is composed of ________________, while actin (thin)
filament is made of ______________, _________________, and
_______________. Ans✓✓ -myosin; actin; troponin; tropomyosin
The structures that carry action potential deep into all regions of a muscle fiber are
called ______________________. Ans✓✓ -t-tubules
The ________________________ ( a specific region of a myosin molecule) is the
only part of the molecule that will interact with actin to create a cross bridge.
Ans✓✓ -myosin head
Which protein binds to Ca2+ and helps initiate muscle contraction? Ans✓✓ -
troponin
An alpha motor neuron and all the muscle fibers it innervates are collectively
called a(n) ___________________________. Ans✓✓ -motor unit
The series of events that begins with excitation of a motor nerve and results in
muscle contraction is called ________________________. Ans✓✓ -excitation
coupling
, ATP is required for ______________________________. Ans✓✓ -muscle
contraction and muscle relaxation
The theory that states that muscle fibers contract when thin and thick filaments
slide past each other is called the _______________________________ theory.
Ans✓✓ -sliding filament theory
When the myosin head pulls the thin filament toward the center of the sarcomere,
the tilting action of the head is known by this special term:
__________________________. Ans✓✓ -power stroke
Type II fibers have a more highly developed ______________________,
suggesting that type II fibers are more adept at delivering Ca2+ into the muscle cell
during contraction. Ans✓✓ -sarcoplasmic reticulum
Type ______ motor units typically contain fewer muscle fibers, meaning that the
force of contraction from this type of motor unit will be
________________________. Ans✓✓ -1, weaker
Type ______ motor units typically engaged for long periods of low-intensity
aerobic exercise. Type ____ fibers are typically engaged during short, higher
intensity exercise and explosive activities. Ans✓✓ -1, 2
The notion that motor units are usually recruited in a fixed, unvarying order to
produce a given force is called the __________________________________.
Ans✓✓ -orderly recruitment principle
