A tendon is ______, whereas an aponeurosis is ______.
cordlike and connects muscles to bones; a broad sheet of dense connective tissue that connects muscles to muscles
Transverse tubules and sarcoplasmic reticulum are well developed in
skeletal and cardiac muscle fibers
The amount of oxygen liver cells require to support the conversion of lactic acid to produce glucose or glycogen is the
Athletes usually experience muscle fatigue less quickly than nonathletes because they
produce less lactic acid
Rigor mortis affects skeletal muscles a few hours after death, due to
a decrease in ATP and increased permeability to calcium
The first event in muscle fiber contraction is that
acetylcholine is released from the end of the motor neuron
Arrange the following steps of muscle fiber contraction in the correct sequence.
1. The muscle impulse reaches the sarcoplasmic reticulum and calcium is released.
2. Thin filaments are pulled over the thick filaments.
3. Calcium floods the sarcoplasm and binds to troponin molecules leaving active sites.
4. The impulse arrives at the synapse and travels through the transverse tubules.
5. The muscle fiber shortens and contracts.
6. Myosin heads bind to exposed active sites on actin, forming cross-bridges.
4, 1, 3, 6, 2, 5
What may occur if the respiratory and circulatory systems to supply enough oxygen to skeletal muscles when used strenuously for a minute or two?
Oxygen debt in muscles
When ATP levels are low, the relationship between ATP and creatine phosphate is that
creatine phosphate supplies energy to regenerate ATP from ADP and phosphate
Skeletal muscles help maintain body temperature in that
the more active they are, the more heat is released
What is the minimum strength of stimulation required to contract a muscle fiber is called
The increase in the number of motor units activated as a result of more intense stimulation is called
In a recording of a muscle twitch, the delay between the time a stimulus is applied and the time the muscle responds is called the
A muscle fiber exposed to a series of stimuli of increasing frequency combines individual twitches (summation) which results in
complete sustained contraction
Activities such as distance swimming and distance running are most likely to stimulate development of
slow fatigue-resistant fibers
What 3 things occur when a muscle undergoes atrophy in response to disuse
1. there is a reduction in capillary networks.
2. the size of actin and myosin filaments decreases.
3. the muscle gets smaller.