Chapter 3 Book
Actin-myosin cross-bridges form when ____
Calcium ions cause active sites to be exposed
A muscle contracts predominately ____ when you throw an object.
Concentrically
The ability to shorten when stimulated is called _____
Contractility
As a person sits from a standing position, what is the predominant contraction type in the lower extremity?
Eccentric
Maximal force is generated in the muscle fibers during ____
Eccentric Contractions
During which of the following maximal contractions is the muscle tension greatest?
Eccentric contraction with the length greater than Lo.
The order of maximum potential force output by contraction type is ____
Eccentric, Isometric, Concentric
The connective tissue component of a skeletal muscle that surrounds fibers is called the _____
Endomysium
A muscle can have more muscle fibers than motor units.
False
All muscles attach to the bone through a tendon
False
Calcium ions are stored within the synaptic terminal
False
Eccentric muscle actions are used to raise a load from the floor
False
Faster concentric actions can produce more force than slower ones.
False
Fusiform fiber arrangement is a type of pennate architecture
False
Maximum muscle power occurs during an isometric contraction
False
Maximum muscle tension can be generated at a muscle length slightly less than the resting length.
False
The dark banding seen in muscle tissue is the result of actin.
False
The fiber force in a pennate muscle is in the same direction as the tendon
False
The muscle moment arm does not affect the torque a muscle can produce
False
The sarcoplasm is the actual contractile unit of the muscle.
False
Type II fibers are oxidative
False
When muscle is stretched it returns to its resting length because of its contractility prosperities.
False
Muscles with lots of sarcomeres in parallel can achieve high ____
Force
Muscle torque differs from muscle force because ____
Force does not consider the duration of the contraction
Both active and passive tension can be generated at muscle lengths ____
Greater than Lo
Functional training ____
Incorporates balance and coordination into each exercise.
Compared with a pennate muscle of the same volume, a fusiform muscle will have ___
More sacrcomeres in series
The perimysium covers the ____.
Muscle Fascicles
What is the muscle structure from smallest to largest?
Myofilaments, myofibrils, fibers, fascicles, muscle
Strength gains during the first eight weeks of an exercise program are primarily due to ____
Neural Factors
A motor unit is ____.
One neuron and all of the muscle fibers it connects to.
The amount of force that can be produced in a muscle is most closely related to _____
Physiologic cross section
Muscle can produce the greatest tension when the length is____
Slightly greater than resting length
In this role, muscle is active to secure a bone so that movement in and adjacent segment can occur.
Stabilizer
The series elastic component in a muscle is hypothesized to be located in the ____
Tendon and Cross-bridges
Which scenario describes an eccentric contraction?
The knee is flexing as the knee extensor muscle group is active
Power is ____
The product of force and velocity.
Calcium ions must be present for cross-bridges to form.
True
Depolarization occurs in both the nerve and the muscle.
True
Each muscle fiber is covered by perimysium.
True
Lengthening of a muscle before contraction increases the force in a concentric contraction.
True
Muscle compartments are separated by fascia.
True
Muscle force is related to the physiologic cross-sectional area
True
Muscles Shorten by 50% to 70% of their resting length. T or F
True
Pennate fiber arrangements have a pennation angle
True
Sarcopenia is the loss of muscle mass seen in aging.
True
The largest tensions can be developed in a muscle through eccentric contractions.
True
The physiologic cross section of a fusiform muscle is the same as the anatomical cross section.
True
The stretch shortening cycle consists of ____ in the same muscle.
A concentric contraction followed by an eccentric contraction.
Muscle fiber depolarization occurs when ___
ACh binds to the muscle fiber.
