Muscle Tissue Study Guide
Rachel is helping her sister install a heavy light fixture. While her sister connects the wires, Rachel must hold the light fixture in place. The wiring is taking longer than expected and Rachel's arms are beginning to tire even though she isn't moving. What type of muscle contraction is occurring in her arms?
Isometric
Which of the following is true concerning isotonic eccentric contraction?
The muscle lengthens but tension remains constant.
Which of the following is true concerning isotonic concentric contraction?
The muscle shortens but tension remains constant.
Which of the following marks the boundaries of a sarcomere?
Z discs
Shortening a muscle while it maintains constant tension is called __________.
an isotonic contraction
Loss of muscle mass from lack of activity is called __________.
atrophy
A muscle twitch produces external tension and moves an object by shortening the muscles during the _____ phase.
contraction
Resistance exercise will most likely cause muscle to __________.
hypertrophy
The thick filaments of the sarcomere are made up mostly of the protein __________.
myosin
A skeletal muscle generates the greatest tension when it is __________.
partially stretched before being stimulated
Skeletal muscle is described as __________.
striated and voluntary
In skeletal muscle, the term that describes the alternating light and dark bands is ___________.
striations
The minimum stimulus needed to cause muscle contraction is called the __________.
threshold
The protein that acts as a calcium receptor in skeletal muscle is __________.
troponin
Skeletal muscle is called ___________, because it is usually subject to conscious control.
voluntary
How many somatic motor neurons stimulate one muscle fiber?
1
How many steps are involved during a muscle contraction?
4
Which of the following contains overlapping thick and thin filaments?
A band
Where in the human body would this tissue be found?
Biceps brachii
Harriet is a body builder, and regularly lifts weights to maintain muscle size. Which of the following statements correctly describes processes related to hypertrophy in skeletal muscles? Check all that apply.
Decrease in tone and size of muscle Increase in number of myofibrils per muscle fiber
Which type of muscle tissue is found in the walls of hollow organs?
Smooth muscle
Which muscle(s) can contract without the need for nervous stimulation?
Smooth and cardiac muscle
Which of the following is predominately made up of myosin?
The thick filament
Based on the size, shape, and ratio of muscle fibers to motor neurons (motor units), rank the following muscles in order of strongest to weakest, starting with #1 being the strongest. Rank the options below.
Gastrocnemius, Orbicularis oculi, Lateral rectus, Brachialis, Quadriceps femoris.
Which of the following is/are a characteristic of skeletal muscle? Check all that apply.
Overlapping thin and thick filaments Striations Excitability Involuntary
Smooth and cardiac muscles are under involuntary control.
True