Muscular System and Digestive System in Human Beings. 2019

            A most hearty welcome to this article. We are happy to place this article in your hands. You will now learn to do small additions. The entire objective has been to systematize the child's process of interaction with the environment so as to make knowledge effective and meaningful. As a suggestion to teachers, I would recommend that they make the child experience the world around him through his senses. For example, the child could be encouraged to use his hands, eyes, ears and nose to observe and feel objects around him. Through simple activities. the child could be made to develop the skill of observation, reporting, collecting information and see relationships. As another example, the child could be made to visit the immediate neighborhood and visit institutions to gain knowledge. Wish you all the best for your studies !

 The muscular system is an organ system consisting of skeletal, smooth, and cardiac muscle. It permits movement of the body, maintains posture, and circulates blood throughout the body. The muscular systems in vertebrates are controlled through the nervous system although some muscles (such as the cardiac muscle) can be completely autonomous. Together with the skeletal system in the human, it forms the musculoskeletal system, which is responsible for the movement of the body. Muscles are firmly attracted to bones by means of tendons. When muscles contract, there is movement at the joint and the bones move either neared to or away from each other. The action of muscles is necessary for all kinds of movements - from the small movements of eyelids to those that demand great strength as when chopping wood with an axe. We use muscles for various movements like talking. laughing, walking, jumping, throwing, etc.

Learning Outcome: Ability to understand the functions of different parts (Muscular ) of the body. 

Voluntary Muscles : Working with our hands, walking, eating, etc. are functions that depend upon our will. Muscles used in these actions are called voluntary muscles. For example, muscles in our arms and legs are voluntary muscles.

Involuntary muscles: Various processes like breathings, blood circulation, digestion are vital function, i.e., they are essential for life, They do not depend upon our will. The muscles of organs which carry out these involuntary function are called involuntary muscles. Functions of organs like the stomach, intestine, heart re carried out in their own fixed manner by involuntary muscles.

There are more than 600 muscles in the human body. Muscles contribute almost 40% of the weight of a healthy adult human body. There are about 30 muscles in the human face. Our eyes, mouth and nose are encircled by small muscles. Expressions like happiness, sadness, fear are expressed by the movements of these muscles of the face.

Types of  3 muscles: 1) Skeletal muscles , 2) Heart or cardiac muscles 3)Smooth muscles . 

Skeletal Muscles : The two ends of each of these muscles are attached to two different bones. Examples of such muscles are muscles of the arms and legs. Their movements are voluntary. They are also responsible for holding the bones of the skeleton together and giving shape to our body.

Heart or cardiac muscles : These muscles bring about the contraction and relaxation (beating) of the heart. Their movement is involuntary. Cardiac muscles cause our heart to relax and contract continuously at a rate of about 70 times per minute.

Smooth muscles : These muscles are present in the internal organs other than the heart. For example, muscles of the stomach, intestine, blood vessels, uterus, etc. Their movements are involuntary and slow. Various vital function of our body, of which we remain quite unaware, are carried out by these special muscles.

           Muscles of which part of your arm contracted and relaxed during the above three actions ?

         Muscles in our body always work in groups. When some muscles contract, other muscles of the same group, relax. This is how muscles help in the proper performance of the various functions of our body. The muscle on the front of the bone in our upper arm is called the biceps. The muscle at the back is called the triceps.

1.  The cardiac muscles do not move.
2. Food enters the stomach and the stomach muscles do not move.

Always Remember :- Muscles of our body must be strong and efficient. Our diet must include proteins and carbohydrates in sufficient quantity for the proper growth and repair of muscles. We must get regular exercise. It makes the muscles strong. We must sit with a straight back, and not with the back hunched or bent. Otherwise, gradually, changes occur in the structure of the vertebrae. Muscles in the shoulder and back begin to hurt. Disorders of the vertebral column may also arise. During exercise, movements of the heart muscles become more rapid. Breathing. too, becomes faster, ensuring a sufficient supply of oxygen and nutrients to various parts of the body. 

The study of muscles is called myology. Contraction is the basic property of muscles. The largest muscle of our body is in the thigh. The smallest muscle is attached to a bone in the ear, called the stapes.

 

         Conversion of food into a soluble form and its absorption into the blood is called digestion. The digestive system consists of the alimentary canal and digestive glands. The total length of alimentary canal is about 9 meters. Its main parts are the mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum and anus. The salivary glands, liver and pancreas are the digestive glands connected to the alimentary canal. Different organs of the degrative system systematically perform the function of digestion. There are different stages in the process of digestion of food and at each stage there is a different organ of the digestive system which performs its specific role. Let us study the structure and function of each organ of the digestive system . 

Teeth : The process of digestion begins with the functions of the teeth in the mouth. There are four types of teeth, namely, incisors, canines, pre-molars and molars. Each type of tooth has a specific function. Each tooth is covered by a hard substance called enamel. Enamel is made of a calcium salt. Saliva contains an enzyme called ptyalin or salivary amylase. Ptyalin converts starch into a sugar called , maltose.               

Enzymes are substances secreted in the body of an organism, which bring about specific chemical reactions. They act as catalysts. Digestive enzymes of the digestive system bring about changes in the food materials. Metabolic processes are impossible without enzymes. Enzymes are a specific type of proteins. They are most active at normal body temperature.

Digestive System

      The human digestive system consists  of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body. The process of digestion has three stages : the cephalic phase, the gastric phase, and the intestinal phase. The first stage, the cephalic phase of digestion, begins with secretions from gastric glands in response to the sight and smell of food. This stage includes the mechanical breakdown of food by chewing, and the chemical breakdown by digestive enzymes, that takes place in the mouth. Saliva contains the digestive enzymes amylase, and lingual lipase, secreted by the salivary and serous glands on the tongue. Chewing, in which the food is mixed with saliva, begins the mechanical process of digestion. This produces a bolus which is swallowed of digestion. This produces a bolus which is swallowed down the esophagus to enter the stomach. The second stage of digestion begins in the stomach with the gastric phase. Here the food is further broken down by mixing with gastric acid until it passes into the duodenum, the first part of the small intestine.

 

        The third stage begins in the duodenum with the intestinal phase, where partially digested food is mixed with a number of enzymes produced by the pancreas. Digestion is helped by the chewing of food carried out by the muscles of mastication, the tongue, and the teeth, and also by the contractions of peristalsis, and segmentation, Gastric acid and the production of mucus in the stomach, are essential for the continuation of digestion. Peristalsis is the rhythmic contraction of muscles that begins in the esophagus and continues along the wall of the stomach and the rest of the gastrointestinal tract. This initially results in the production of chime which when fully broken down in the small intestine is absorbed as chile into the lymphatic system. Most of the digestion of food takes place in the small intestine. Water and some minerals are reabsorbed back into the blood in the colon of the large intestine. The waste products of digestion (feces) are defecated from the rectum via the anus. 

Mouth : Digestion of food begins in the mouth. Food is chewed with the help of teeth into very small pieces.

Salivary glands : Saliva is produced in the salivary glands in the mouth cavity, located in front of the ears, near the pharynx and below the tongue. It is carried to the mouth via ducts. It is mixed with food during the process of chewing.

Pharynx / Throat : The oesophagus and trachea open into the pharynx. 

Oesophagus : It is a tube leading from the pharynx to the stomach. It pushes the food towards the stomach.

Liver : The liver is the largest gland in the body. It has a rich supply of blood. Its main function is storage of glucose. The gall bladder is situated below the liver. It stores the bile, the digestive juice secreted by the liver. When bile is carried into the small intestine, it mixes with the food there and helps in the digestion of fast. Bile contains bile salts.

Pancreas : The pancreas secretes the pancreatic juice that contains various enzymes.

Stomach : The large sac-like part of the alimentary canal is called the stomach. The gastric glands of stomach secrete gastric juice. Food that has entered stomach is churned. Three components of gastric juice, namely, hydrochloric acid, pepsin and mucus are mixed with food here and it becomes acidic. Mainly proteins are digested in the stomach, Due to the churning and the action of gastric juice, food becomes a semi-solid slurry which is slowly pushed into the small intestine.

Stomach : The large sac-like part of the alimentary canal is called the stomach. The gastric glands of stomach secrete gastric juice. Food that has entered stomach is churned. Three components of gastric juice, namely, hydrochloric acid, pepsin and mucus are mixed with food here and it becomes acidic. Mainly proteins are digested in the stomach, Due to the churning and the action of gastric juice, food becomes a semi-solid slurry which is slowly pushed into the small intestine.

Small intestine: The small intestine is about 6m long. Most of the digestion and absorption of food takes place here. Three different digestive juices are mixed with the food in the small intestine. Absorption into the blood, of nutrients obtained by the digestion of food, also occurs in the small intestine.

Large intestine : The large intestine is about 1.5m long. Only water is absorbed in the large intestine. A small part called the 'appendix' is attracted to the first part of large intestine. Undigested remains of the food digested in the small intestine enter the large intestine. Undigested material is thrown out of the body through the anus.

Are we putting our health at risk ? 
        Physical health is extremely important in personality development. When all our organ system function properly, we say that we are in good health. However, harmful habits like smoking, chewing of tobacco, drinking alcohol affect our health adversely.

Effects of tobaccos, alcohol, smoking on the digestive system 
          If we consume any tobacco products, the mouth, pharynx, alimentary canal and other organs of the digestive system cannot function properly. It causes problems like vomiting. nausea, and headache. Besides, tobaccos particles stick to teeth, gums and skin of the mouth cavity and slowly cause injury to those parts resulting in their dysfunction. This causes swelling of the gums and pain when moving the jaws. The pharynx and intestine become inflamed and the condition further progresses into cancer leading to death. 


My Role 

• slogans against tobacco consumption, smoking, drinking alcohol, etc. and displaying them in the classroom and the neighborhood and friends. Keeping a watch on whether one's surroundings are tobaccos - free.
• Composing an oath against addiction and taking the oath in the class and also during assembly. 
• Making parents and friends aware of such instances in the neighborhood.

31st  May is World No Tobaccos Day

 and

7 th  April is World Health Day.

        We hope that our humble effort to inspire, encourage and ignite the minds of our very young students will be appreciated by parents.