Biology: Muscular System Functions and Types

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What type of fibers do sprinters typically possess a high percentage of?

Fast-twitch fibers (correct)

Type IIa fibers

Slow-oxidative fibers

Slow-twitch fibers

What is the ratio of muscle fibers to motor neurons in eye muscles?

5:1

1:1 (correct)

10:1

2:1

What is the result of endurance and resistance training on fast fibers?

They become more oxidative

They remain unchanged (correct)

They are converted to slow fibers

They are lost

What is the primary difference between hypertrophy and hyperplasia?

Increase in size versus increase in number Signup and view all the answers

At what age does the rate of muscle mass loss increase?

50 years Signup and view all the answers

What type of muscle contraction occurs when a muscle produces force but its length increases?

Isotonic eccentric Signup and view all the answers

What is the role of muscles in the musculoskeletal system?

To provide shape and movement Signup and view all the answers

During muscle contraction, what happens to the distance between the Z-lines of the sarcomere?

It decreases Signup and view all the answers

What is the term for the theory that explains muscle contraction?

Sliding filament theory Signup and view all the answers

What is the muscle function that allows for gradation of muscle strength?

Multiple motor unit summation Signup and view all the answers

What percentage of total body weight is made up of skeletal muscles?

40-50% Signup and view all the answers

What is a characteristic of skeletal muscles?

They only pull Signup and view all the answers

What is the relationship between the number of motor units recruited and the force generated?

More motor units result in greater force Signup and view all the answers

What is the function of the Golgi tendon organ in muscle?

To detect tension developed in muscle Signup and view all the answers

What is the effect of initial muscle length on force generation?

There is an 'ideal' length for optimal force generation Signup and view all the answers

How does the speed of movement relate to the type of muscle fibers present?

At any absolute force, the speed of movement is faster in muscles with a higher percent of fast-twitch fibers Signup and view all the answers

What is the relationship between the velocity of movement and the force generated?

Force decreases with increasing movement speed beyond a certain velocity Signup and view all the answers

What is the function of the muscle spindle?

To detect dynamic and static changes in muscle length Signup and view all the answers

What surrounds individual muscle fibers?

Endomysium Signup and view all the answers

What is the pocket formed around the motor neuron by the sarcolemma called?

Motor end plate Signup and view all the answers

What is broken down by myosin ATPase during muscle contraction?

ATP Signup and view all the answers

What type of muscle fibers are also known as fast-glycolytic fibers?

Type IIb fibers Signup and view all the answers

What is the storage site for calcium ions in muscle fibers?

Sarcoplasmic reticulum Signup and view all the answers

What is the term for the depolarization of the muscle fiber membrane in response to acetylcholine release?

End-plate potential Signup and view all the answers