Answer
The main functions of the muscular system are:
1. Mobility
2. Stability
3. Posture
4. Circulation
5. Respiration
6. Digestion
7. Urination
8. Childbirth
9. Vision
10. Organ protection
11. Temperature regulation
Work Step by Step
The main functions of the muscular system are:
1. Mobility
The muscular system’s main function is to allow movement. When muscles contract, they contribute to the gross and fine movement.
Gross movement refers to large, coordinated motions and includes:
walking
running
swimming
Fine movement involves smaller movements, such as:
writing
speaking
facial expressions
The smaller skeletal muscles are usually responsible for this type of action.
Most muscle movement of the body is under conscious control. However, some movements are reflexive, such as withdrawing a hand from a source of heat.
2. Stability
Muscle tendons stretch over joints and contribute to joint stability. Muscle tendons in the knee joint and the shoulder joint are crucial in stabilization.
The core muscles are those in the abdomen, back, and pelvis, and they also stabilize the body and assist in tasks, such as lifting weights.
3. Posture
Skeletal muscles help keep the body in the correct position when someone is sitting or standing. This is known as posture.
Good posture relies on strong, flexible muscles. Stiff, weak, or tight muscles contribute to poor posture and misalignment of the body.
Long-term, bad posture leads to joint and muscle pain in the shoulders, back, neck, and elsewhere.
4. Circulation
The heart is a muscle that pumps blood throughout the body. The movement of the heart is outside of conscious control, and it contracts automatically when stimulated by electrical signals.
Smooth muscle in the arteries and veins plays a further role in the circulation of blood around the body. These muscles maintain blood pressure and circulation in the event of blood loss or dehydration.
They expand to increase blood flow during times of intense exercise when the body requires more oxygen.
5. Respiration
Breathing involves the use of the diaphragm muscle.
The diaphragm is a dome-shaped muscle located below the lungs. When the diaphragm contracts, it pushes downward, causing the chest cavity to get bigger. The lungs then fill with air. When the diaphragm muscle relaxes, it pushes air out of the lungs.
When someone wants to breath more deeply, it requires help from other muscles, including those in the abdomen, back, and neck.
6. Digestion
The muscular system allows for movement within the body, for example, during digestion or urination.
Smooth muscles in the gastrointestinal or GI tract control digestion. The GI tract stretches from the mouth to the anus.
Food moves through the digestive system with a wave-like motion called peristalsis. Muscles in the walls of the hollow organs contract and relax to cause this movement, which pushes food through the esophagus into the stomach.
The upper muscle in the stomach relaxes to allow food to enter, while the lower muscles mix food particles with stomach acid and enzymes.
The digested food moves from the stomach to the intestines by peristalsis. From here, more muscles contract to pass the food out of the body as stool.
7. Urination
The urinary system comprises both smooth and skeletal muscles, including those in the:
bladder
kidneys
penis or vagina
prostate
ureters
urethra
The muscles and nerves must work together to hold and release urine from the bladder.
Urinary problems, such as poor bladder control or retention of urine, are caused by damage to the nerves that carry signals to the muscles.
8. Childbirth
Smooth muscles in the uterus expand and contract during childbirth. These movements push the baby through the vagina. Also, the pelvic floor muscles help to guide the baby’s head down the birth canal.
9. Vision
Six skeletal muscles around the eye control its movements. These muscles work quickly and precisely, and allow the eye to:
maintain a stable image
scan the surrounding area
track moving objects
If someone experiences damage to their eye muscles, it can impair their vision.
10. Organ protection
Muscles in the torso protect the internal organs at the front, sides, and back of the body. The bones of the spine and the ribs provide further protection.
Muscles also protect the bones and organs by absorbing shock and reducing friction in the joints.
11. Temperature regulation
Maintaining normal body temperature is an important function of the muscular system. Almost 85 percent of the heat a person generates in their body comes from contracting muscles.
When body heat falls below optimal levels, the skeletal muscles increase their activity to make heat. Shivering is one example of this mechanism. Muscles in the blood vessels also contract to maintain body heat.
Body temperature can be brought back within normal range through the relaxation of smooth muscle in the blood vessels. This action increases blood flow and releases excess heat through the skin.
