Human Muscular System

The UPSC mains GS-3 paper syllabus has various subjects like Economics, Science and Technology. Science and technology in UPSC is mostly concerned with current Affairs. but it is necessary to understand the basics of science. Human Body consists of some of the most complex systems. Human Muscular System is helpful in the movement of the body, The muscles can move voluntarily and involuntarily.

TOPICS

• What is Muscular system
• Functions of Muscles system
• Classification of Muscular system
• 3 types of muscles

WHAT IS MUSCULAR SYSTEM

Human muscle system, the muscles of the human body that work the skeletal system, that are under voluntary control, and that are concerned with movement, posture, and balance. Broadly considered, human muscle—like the muscles of all vertebrates—is often divided into striated muscle (or skeletal muscle), smooth muscle, and cardiac muscle. Smooth muscle is under involuntary control and is found in the walls of blood vessels and of structures such as the urinary bladder, the intestines, and the stomach. Cardiac muscle makes up the mass of the heart and is responsible for the rhythmic contractions of that vital pumping organ; it too is under involuntary control. With very few exceptions, the arrangement of smooth muscle and cardiac muscle in humans is identical to the arrangement found in other vertebrate animals.

FUNCTIONS OF MUSCLES

1. 1. Movement
   2.  Maintenance of posture and muscle tone
   3.  Heat production
   4.  Protects the bones and internal organs.

CLASSIFICATION  OF MUSCLES

Functionally

1. Voluntarily – can be moved at will eg. Hand muscles, Leg muscles, Shoulder muscles
2. Involuntarily – can’t be moved intentionally e.g Stomach Muscles, Heart Muscles, lung muscles

Structurally

1. Striated – have stripes across the fiber
2. Smooth – no striations

3 TYPES OF MUSCLES

• Skeletal muscle:

This type of muscle creates movement in the body. There are more than 600 skeletal muscles, and they makes up about 40 percent of a person’s body weight. When the nervous system signals the muscle to contract, groups of muscles work together to move the skeleton. These signals and movements are nearly involuntary, yet they do require conscious effort. However, humans do not need to concentrate on individual muscles when moving.

• Cardiac muscle:

Cardiac muscle is involuntary muscle. This type makes up the walls of the heart and creates the steady, rhythmic pulsing that pumps blood through the body from signals from the brain. This muscle type also creates the electrical impulses that produce the heart’s contractions, but hormones and stimuli from the nervous system can also affect these impulses, such as when your heart rate increases when you’re scared.

• Smooth muscle:

Smooth muscle makes up the walls of hollow organs, respiratory passageways, and blood vessels. Its wavelike movements propel things through the bodily system, such as food through your stomach or urine through your bladder. Like cardiac muscle, smooth muscle is involuntary and also contracts in response to stimuli and nerve impulses.