Question

How many muscles are there in the human body?
a. $320$
b. $602$
c. $572$
d. $639$

Answer 1

Human body has different muscles coming from different body parts including head muscles, neck muscles, trunk muscles, upper and lower limbs muscles. The exact number of muscles is difficult to determine because different sources group the muscles in different ways.

Complete answer:
• As we know that the human body possesses different muscles that arise from different parts of our body. Muscle fibres in our body are composed of myofibrils which in turn are composed of actin and myosin filaments and are the basic functional units of muscle fibres.
• It is estimated that our body consists of approximately $639$ muscle named as skeletal muscles along with smooth muscles and cardiac muscles.
• Skeletal muscles can be found in all parts of our body that help in enabling the movement, maintaining the structural support and posture, generating the heat to maintain the temperature of our body. We can control these muscles unlike cardiac and smooth muscles.
• These muscles include the face, neck, and head muscles such as Zygomaticus which is involved in facial expression and lifts the mouth corners when we speak or smile. Then the Masseter muscles which are found in our jaw and help in chewing food and opening and closing of our mouth. Extraocular muscles of our eyes that controls the eyes movement as well as its opening and closing. Then the tongue muscles which are responsible for the movement of our tongue while speaking. Lastly we have sternocleidomastoid muscles which are responsible for the movement of our head from side to side or forward tilting.
• Then we have the muscles of our trunk that includes Erector spinae to support the spine and movement of our middle body, oblique and intercostal muscles that help in side movements and inhaling exhaling respectively.
• Then we have diaphragm muscles which are also involved in breathing and lastly the Levator ani which are the muscles around our pelvis and help in urination and bowel movements.
There are many more muscles left like biceps, triceps, deltoid muscles, trapezius muscles etc.

Hence, the correct answer is option (D).

Note: We have smooth muscles which are involved in functioning of the digestive system, reproductive system, cardiovascular system and renal system along with the muscles or cardiac allowing the heart to beat in response to electrical impulses.