Final Answer:
Muscle contraction is influenced by factors such as a) how stretched the muscle was just before stimulation, b) stimulation frequency, c) muscle fatigue, and d) the temperature of the muscle.
Step-by-step explanation:
a) The degree of muscle stretch before stimulation, known as the length-tension relationship, affects the force of contraction. Optimal overlap of actin and myosin filaments occurs within a specific range of muscle length.
b) Stimulation frequency, or the rate at which motor neurons fire, impacts muscle contraction. Higher frequencies can lead to summation of twitches and increased force.
c) Muscle fatigue, a result of prolonged activity, diminishes a muscle's ability to contract due to factors like depletion of energy stores or accumulation of metabolic byproducts.
d) The temperature of the muscle influences enzyme activity and metabolic reactions, affecting the speed and efficiency of muscle contraction.
factors a. b. c. and d. is affect the muscle contraction.