There are approximately 640 skeletal muscles within the typical human, and almost every muscle constitutes one part of a pair of identical bilateral muscles, found on both sides, resulting in approximately 320 pairs of muscles, as presented in this article. Nevertheless, the exact number is difficult to define because different sources group muscles differently, e.g. regarding what is defined as different parts of a single muscle or as several muscles. Examples range from 640 to 850.
The muscles of the human body can be categorized into a number of groups which include muscles relating to the head and neck, muscles of the torso or trunk, muscles of the upper limbs, and muscles of the lower limbs.
There is no universally agreed definition of what a skeletal muscle is, so there are differences of opinion as to where one muscle ends and another begins, hence the variation in numbers. There are also several small skeletal muscles in the human body that may or may not be present in certain individuals due to genetic factors. For example the palmaris longus muscle is not present in approximately 14% of the population, and the peroneus quartus is a muscle rarely found in the human body.
There is also another kind of muscle called smooth muscle, which cannot be consciously controlled. It’s near impossible to say how many smooth muscles there are in the body since they can vary in size greatly and are not exactly easy to count.
A baby is born with 300 bones. An adult has 206. Babies bone fuse together making less in an adult.
Also, in the human body there are 350 bones when you are first born but by the time your an adult some of your bones would have fused together to make only 206 bones.
Smooth muscle: This muscle tissue is called involuntary because it is NOT under conscious control. Involuntary means you do not have to think about it. Involuntary muscle tissue is found in the internal organs; namely the digestive tract, respiratory passages, urinary and genital ducts, urinary bladder, gallbladder, walls of the blood vessels. Yep! Your blood vessel walls are also muscle tissue. Another great reason to exercise and pump the blood.
Striated muscle: This muscle tissue is found in all skeletal muscles, and movement is under conscious control. It also occurs in the tongue, pharynx, and upper portion of the esoophagus. Voluntary muscles are under conscious control because you would consciously tell them what to do. If you say, “arm, move” it moves!
Cardiac muscle: This muscle tissue is only found in the heart. The fibers branch and form a continuous network. At certain intervals, there are prominent bands or intercalated disks that cross the fibers. Some fibers are called Purkinje fibers, and they form the impulse-conducting system of the heart.
Striated muscles can be also called skeletal or voluntary muscles. This group of muscles refers to muscles that the human body has control of. These include the muscles that are responsible for movement of the bones, and also include the facial muscles. Striated muscles are muscles that are the ones generally injured during physical activity or sports. The smooth muscles are involuntary and are controlled by the part of the human body known as the autonomic nervous system. These muscles are responsible for movement of internal organs such as the secretory glands and organs of the gastrointestinal tract.