Muscle is excitable because it can be stimulated in order to cause contraction. Stimulation comes from the nervous system via electric signals/action potential that travels frâ¦om neuron through axon to muscle tissue.
Breed Profile--Written By Tiami Coleburg Breed: Labrador Retriever Owner Level: Suitable for some active and involved first time owners. Average Life Span: 12-14 years Average Weight: Male weights range 65-80 pounds. Female weights range 55-70 pounds. Average Weight Male height ranges from 22 1/2 to 24 1/2 inches high at the shoulder. Female height ranges from 21 1/2 to 23 1/2 inches at the shoulder. Color And Coat: True Labrador Retrievers only come in: black, shades of chocolate, and yellow.
The breed standards for the two kennel clubs differ slightly. The mature American Labrador Retriever stands between 21.5 and 24.5 inches at the shoulder, while the height of the English Labrador Retriever is slightly less, from 21.5 to 22.5 inches. In both types, males are larger than females.