Question

Put the motor units (Listed by innervation ratio) in order from first activated to last to be activated.

A: 1:100
B: 1:25
C: 1:1000

Answer 1

The motor units in order from first activated to last to be activated are: C, A, B.

Step-by-step explanation:

The order of motor units from first activated to last to be activated is:

1. Motor unit C with an innervation ratio of 1:1000
2. Motor unit A with an innervation ratio of 1:100
3. Motor unit B with an innervation ratio of 1:25

Motor units are activated based on the size of the motor neurons and the contractile strength needed. Smaller motor units with smaller, lower-threshold motor neurons are activated first, followed by larger motor units with bigger, higher-threshold motor neurons.