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.
How big are Labrador Retrievers? About 21-25 inches at the shoulder, with males usually in the higher half of that range, and females usually in the lower half. Weight can be as low as 55 pounds, but is usually 65-80 pounds. Unfortunately, the trend seems to be for heavier and heavier Labs, with a lot of individuals topping 90 pounds. I say unfortunately because heavier weight isn't good for their joints.