The following steps are involved in muscle contraction: (1) The sequence of events leading to contraction is initiated somewhere in the central nervous system, either as voluntary activity from the brain or as reflex activity from the spinal cord.
The average Mexican man weighs 165 pounds and stands 5 feet 4 1/2 inches tall, while the median figures for Mexican women are 151 pounds and 5 feet 2 inches, according to a study released by a group representing Mexico's clothing industry.
In other cultures, age at marriage may be slightly lower. For example, in Mexico the mean age of marriage currently is 23.3 years for men and 18.4 years for women. This has increased as well, reflecting Mexicoâs increasing industrialization.