LS 2 2 The Musculatory System

Learning Strand 2: Scientific Literacy and Critical Thinking Skills

1. The MUSCULAR SYSTEM PART i Learning strand 2 Michael Cachero Gelacio / Teacher III – District I ALS Coordinator

2. Let’s see what you already know To find out what you already know about the topics to be discussed, answer the questions below. Write your answers in a ½ crosswise sheet of paper. Enumerate the seven functions of the muscular system. Name the two major types of muscles that make up the muscular system. Describe how the muscular system works during movement .

3. How the muscular system functions

4. Muscular system Composed of muscles that are arranged in a way that enables you to move and do a lot of things. An adult has 620 identified muscles. This figure only represents the skeletal muscles, the muscles that are attached to bones .

5. Muscular system Muscles are living tissues that have the special ability to contract or shorten, thus producing movements of internal and external body parts. Muscles attach two bones to each other through TENDONS .

6. SKELETAL MUSCLES The skeletal muscles of the muscular system are attached to the bones of the skeletal system of the human body. These allow the body to move and accomplish a lot of things . You need your muscles to jump.

7. SKELETAL MUSCLES You use your leg muscles to run . You use your facial muscles to smile and express happiness.

8. Functions of SKELETAL MUSCLES VOLUNTARY MOVEMENTS OF THE BODY PROVIDE PROTECTION TO THE INTERNAL ORGANS .

9. FunctionS of SMOOTH MUSCLES Feel very smooth and lack the rough appearance of other kinds of muscles. FACILITATING THE MOVEMENT OF INTERNAL ORGANS.

10. Kinds of SMOOTH MUSCLES It pumps blood throughout your body. The muscles found in the heart are called CARDIAC MUSCLES . HEART

11. SMOOTH MUSCLES The smooth muscles of the stomach contract to digest food. DUODENUM

12. SMOOTH MUSCLES The smooth muscles of your intestines allow food to be digested and propelled towards the anus. INTESTINES

13. SMOOTH MUSCLES The smooth muscles of the Uterus contract to allow females to deliver a baby. UTERUS

14. SMOOTH MUSCLES The smooth muscles of your bladder and ureters control urination. URETHRA

15. SMOOTH MUSCLES When you inhale, your diaphragm contracts pulling your lungs down and making them expand or inflate to allow air to enter. When you exhale, your diaphragm relaxes, making lungs deflate. The deflation of your lungs allows air to exit from your body. DIAPHRAGM

16. FUNCTIONS OF Muscular system MUSCLES PROVIDE HEAT THAT THE BODY NEEDS TO FUNCTION PROPERLY.

17. The muscular system is a system of voluntary and involuntary muscles in the human body. It greatly contributes to the well-being of the body by: allowing movement to occur; providing protection to internal organs; facilitating the movement of internal organs such as the heart, lungs, intestines and bladder to function properly; and producing heat that the body needs to function properly. ♦ Muscles produce movement by contracting or shortening. Some actions of the muscular system are voluntary as in the case of the skeletal muscles that are attached to the bones of the body. Some are involuntary as in the case of the smooth muscles especially the muscles lining the walls of the intestines

18. LET’S SEE WHAT YOU HAVE LEArned DIRECTION: Write True in the blank if the statement is correct. Write False if it is not . ________ 1. The human muscular system is made up of different kinds of muscles. ________ 2. Muscles only move voluntarily. ________ 3. Muscles are able to work because of their strength. ________ 4. Contraction of the smooth muscles allows the body to move. ________ 5. The muscular system makes movement possible through a series of contractions. ________ 6. The muscular system provides some protection to vital organs like the intestines and the stomach. ________ 7. Life as we know it is still possible without the muscular system. ________ 8. Childbirth is made possible by the contraction of the uterus. ________ 9. The muscular system does not provide heat to the body. _______ 10. Shivering is the body’s own way of producing heat.

19. Structure of the muscular system An adult has 620 skeletal muscles arranged in the best possible way to make parts of the body move. In males, the skeletal muscles make up 42% of the adult body weight. In females, who are less heavy generally, skeletal muscles comprise 36% of their entire body weight.

20. Structure of the muscular system The skeletal muscles are so named because they are closely associated with the skeletal system. The skeletal system is made up of bones that form the foundation and give shape to the human body

21. Structure of the muscular system The skeletal muscles act like the walls of a house, which connect bones to each other. Although the bones are already connected to each other by tough fibrous bands of tissue called ligaments , THE SKELETAL MUSCLES REINFORCE THESE CONNECTIONS AND MAKE THEM STRONGER.

22. Structure of the muscular system Muscles are attached to at least two bones in at least two points, one on each point. These points are called the ORIGIN and INSERTION .

23. Structure of the muscular system There are also complicated muscles in the body which have three or more bone attachments! These attachments are needed to provide more stability to the movement of the bones. This is especially needed for work requiring more effort like lifting weights .

24. Structure of the muscular system The biceps and triceps muscles are ANTAGONISTIC MUSCLES or opponent muscles . Antagonistic muscles are located opposite each other.

25. Structure of the muscular system SYNERGISTIC MUSCLES are groups of muscles work together to perform a similar action.

26. LET’S SEE WHAT YOU HAVE LEArned DIRECTION: Write True in the blank if the statement is correct. Write False if it is not . ______ 1. There are 320 skeletal muscles in the human body. ______ 2. The skeletal muscles move voluntarily. ______ 3. All muscles are of the same size. ______ 4. All muscles are of the same shape. ______ 5. Skeletal muscles are attached to bones. ______ 6. Tendons attach muscles to bones. ______ 7. Muscles primarily work by contracting. ______ 8. Contracting one’s muscles makes bones move away from each other. ______ 9. The triceps and biceps of the upper arm are examples of synergistic muscles. ______ 10. Opponent muscles contract at the same time.

27. SMOOTH MUSCLES Smooth muscles are made up of a special form of muscle tissue under AUTOMATIC CONTROL OF THE NERVOUS SYSTEM.

28. SMOOTH MUSCLES These are involuntary muscles that mediate functions such as circulation, digestion, urination and reproduction, which are necessary for living and the continuation of life.

29. Stomach muscles The stomach is the part of the digestive system found in the abdomen. It functions primarily to digest food through the secretion of acids. When the smooth muscles of the stomach contract, food is pushed towards the intestines to continue the process of digestion until it is finally expelled. This process is called PERISTALSIS . Without peristalsis, digestion of food will not be possible.

30. What have you learned Match the items in Column A to those in Column B. Write the answers in the space provided. Column A Column B ____ 1. Voluntary muscles a . One of the functions of muscles ____ 2. Cardiac muscles b . Move under conscious control ____ 3. Involuntary muscles c . Produce movement even without one’s knowledge ____ 4. Movement d . Muscles attached to bones ____ 5. Contraction e . Muscles of the heart ____ 6. Antagonistic muscles f . Cause muscles to move ____ 7. Heat production g . Make up internal organs ____ 8. Smooth muscles h . Opponent muscles ____ 9. Synergistic muscles i . Role of muscles in regulating movements ____ 10. Skeletal muscles j . Muscles that contract together

31. The MUSCULAR SYSTEM PART Ii Learning strand 2

32. Let’s see what you already know To find out what you already know about the topics to be discussed, answer the questions below. Write your answers in a ½ crosswise sheet of paper. Enumerate the three major types of muscle tissues. What is the basic contractible unit of muscles? What makes cardiac muscles different from skeletal and smooth muscles? State three injuries or diseases that can affect the muscular system. Cite two ways to take good care of the muscles of your body .

33. The muscle tissue Muscles are made up of fibers that have two very special properties. EXCITABILITY . R efers to the muscles’ ability to respond to electrical signals provided by the nerves of the nervous system .

34. The muscle tissue CONTRACTION enables the body to make both internal and external movements. Contraction involves shortening of the muscle fibers.

35. Two types of muscles VOLUNTARY MUSCLES Muscles that are under conscious control and produce voluntary movements by pulling against the bones of the skeleton to which they are attached by means of TENDONS.

36. Voluntary muscles THE SKELETAL MUSCLES In terms of performance, they are like high-speed engines. They work fast and powerfully but easily get tired because of the high amounts of energy needed to make them move . Skeletal muscles are also called STRIATED (striped ) muscles because if seen under a microscope, their individual fibers are visible.

37. Voluntary muscles The skeletal muscles are HIGHLY VASCULAR . This means they are rich in blood supply needed for the fast, powerful movements of the body . Skeletal muscle cells are cylindrical in shape. They are also very long.

38. Voluntary muscles MYOFIBRIL = i ndividual fiber in a bundle. SARCOLEMMA = A group of myofibrils when enclosed in a membrane. The word sarco means “flesh” in Latin .

39. Voluntary muscles A BANDS = dark bands I BANDS = light bands. Have thin lines traveling through the center of a myofibril called Z lines. SARCOMERE = area between two Z lines, the contractile unit of the myofibril.

40. Voluntary muscles MUSCLE FIBER = myofibrils that are packed together as a single unit inside the sarcolemma. MUSCLE FASCICULI (plural of fasciculus) muscle fibers that are packed together in bundles. MUSCLE = Groups of muscle fasciculi.

41. Muscle movement Movement is achieved through a complex series of protein interactions inside each sarcomere, the basic contractible unit of a muscle.

42. Let’s review Write the letter of the description in Column B that matches the word or phrase in Column A Column A Column B _____1. Voluntary muscle a . basic contractible unit of the muscular system _____ 2. Striated b . rich in blood supply _____ 3. Muscle fasciculus c . muscle movement _____ 4. I band d . skeletal muscle cell _____ 5. Contraction e . dark band _____ 6. Sarcolemma f . muscle bundle _____7. Sarcomere g . comprised mostly of skeletal muscles _____ 8. A band h . light band _____ 9. Vascular i . striped in appearance ____ 10. Myofibril j . covering membrane of myofibrils

43. Two types of muscles INVOLUNTARY MUSCLES are the muscles that are not under conscious control. They are also called smooth muscles .

44. INVOLUNTARY MUSCLES The smooth muscles can be found in hollow VISCERA or internal organs such as the stomach, intestines, bladder, uterus, walls of the blood vessels, glands and even skin.

45. INVOLUNTARY MUSCLES The smooth muscles do not appear striated when seen under a microscope. Internal organs need to create sustained, prolonged movements that are less powerful and thus have no need for striations except for the heart .

46. INVOLUNTARY MUSCLES The only INVOLUNTARY MUSCLE that is striated is the heart. The heart pumps blood throughout the body 24 hours a day, seven days a week without fail .

47. INVOLUNTARY MUSCLES CARDIAC MUSCLES Have dark stripes called INTERCALATED DISKS . These disks mark the points of strong adhesion between the cells of the cardiac muscles which must withstand strong pressures during contraction .

48. Let’s SEE WHAT YOU HAVE LEARNED Answer the following questions briefly . What are the two general classifications of muscles? Differentiate one from the other. Why are voluntary muscles striated? Explain your answer. How are cardiac muscles similar to skeletal muscles? How are they different? Explain your answers. Why are cardiac muscles, though involuntary, striated? Explain your answer .

49. COMMON DISEASES AND INJURIES Learning strand 2

50. MUSCLE STRAIN The muscular system, tough as it is, is still prone to diseases. It needs to be taken care of too! The following are some of these injuries and diseases. is a tear or stretch in the muscle fiber or the tendon that connects a muscle to a bone. It can range from a relatively mild injury, with some muscle fibers being torn, to a large muscle tear with swelling and bleeding.

51. MUSCLE STRAIN Muscle strains are usually caused by: MUSCULAR IMBALANCE – This occurs when one side of the joint is stronger than the other or the opposite muscle does not relax while the other contracts. This can be traced in most cases to either a lack of conditioning or overtraining one muscle group versus an opposing muscle group, e.g., the front of the thighs (quadriceps) versus the back of the thighs (hamstrings ). MUSCLE FATIGUE – This occurs when additional stress is put on a muscle and its connective tissue.

52. MUSCLE STRAIN The more active a person is, the greater his/her risk of injury. Poorly conditioned people are also at risk when they do strenuous activities without proper preconditioning. The following are the signs/symptoms of muscle strain : 1. Pain in a muscle group or joint; 2. Swelling of a muscle group or joint; and 3. Tenderness in a muscle group or joint.

53. FIRST AID TIPS FOR MUSCLE STRAIN Reduce your activities. Avoid movements that place stress on the injured area. Apply a cold compress or some ice on the injured area. Do this for 24 to 48 hours after the injury. You may try applying a hot compress or an analgesic balm on the injured area on the third day or as soon as the swelling is gone. Apply an elastic bandage to the injured area. Elevate the injured area for 24 to 48 hours depending on the severity of the injury. Taking in aspirin may also help reduce the pain and inflammation. Just be sure to use it as directed. Try slow gentle stretches. Avoid stretching for a few days if the injury is severe; do movements that promote circulation instead, e.g., slow walking, gentle arm rotation exercises, etc. Be sure to properly condition your body first before doing strenuous activities next time. Strengthen major muscle groups with weight training. Consult a doctor if: there is excessive swelling, bruising and/or tenderness in the injured area; the pain prevents you from moving.

54. MUSCLE SPASMS OR CRAMPS C ontractions of the muscles which are often painful. Muscle twitching is the result of minor local muscle contractions or the uncontrollable twitching of a single muscle group served by a single motor nerve fiber or filament.

55. MUSCLE SPASMS OR CRAMPS Muscle spasms or cramps are commonly caused by : 1. muscle fatigue; 2. heavy exercise; 3. dehydration; and 4. pregnancy.

56. MUSCLE SPASMS OR CRAMPS Muscle twitching can be caused by: a benign (of a mild form), non-pathologic (not caused by disease or disorders) fasciculation which: a . often affects the eyelids, calf or thumb; and b . is normal or common and is often triggered by stress and anxiety; a diet deficiency; drug overdose; and a side effect of taking in drugs such as diuretics (drugs that increase the volume of urine produced and excreted) , corticosteroids (steroid hormones) and estrogens (steroid hormones, produced mainly by the ovaries, that control the growth and functioning of the female sex organs and the appearance of female secondary sexual characteristics).

57. MUSCLE SPASMS OR CRAMPS Muscle cramps most often occur in the foot or calf muscles. Muscle twitches are minor and often go unnoticed. Some are common and normal while others indicate a neurologic disorder. The following are some first-aid treatments for muscle cramps: 1 . slow stretching exercises; 2 . following prescribed therapy; and 3 . taking in prescribed analgesics or pain relievers. But you should consult your doctor if: there are severe, prolonged or recurring muscle spasms or cramps that are unexplained or that aren’t relieved by simple stretching exercises; and there are prolonged or persistent muscle twitches that are unexplained.

58. POLIOMYELITIS what is commonly known as polio is a disorder caused by a viral infection (poliovirus) that affects the whole body including muscles and nerves. Severe cases may cause permanent paralysis or even death. It is usually manifested by loss of muscle tone and bulk. People with polio usually have unequally sized legs which cause impaired movement.

59. POLIOMYELITIS Communicable disease caused by infection with the poliovirus Transmission of the virus occurs by: A B C direct person-to-person contact by contact with infected secretions from the nose or mouth by contact with infected feces

60. Three basic patterns of polio 1 SUBCLINICAL INFECTIONS - are infections that may go unnoticed. These have no symptoms or if they do, the symptoms last for only 72 hours or less. These said symptoms include: slight fever headache malaise (general discomfort or uneasiness) sore throat vomiting A B C D E

61. Three basic patterns of polio 2 NONPARALYTIC POLIOMYELITIS - may occur after recovery from a subclinical infection. Its symptoms may last for one to two weeks. These include: moderate fever A headache B stiff neck C vomiting D diarrhea E back pain F irritability G pain or stiffness of the back, arms, legs and abdomen H muscle tenderness and spasm in any area of the body I neck pain J fatigue or excessive tiredness K leg pain (especially in the calf muscles) L painful skin rash or lesion M

62. Three basic patterns of polio 3 PARALYTIC POLIOMYELITIS – This may occur after recovery from subclinical infections. Its symptoms include : fever, occurring five to seven days before the other symptoms A headache B stiff neck and back C muscle weakness characterized by rapid onset which can progress to paralysis depending on where it affects the spinal cord D abnormal sensations of an area E oversensitivity to touch F difficulty in urinating G constipation H

63. Three basic patterns of polio bloated abdomen I difficulty in swallowing J muscle pain K muscle contractions or spasms particularly in the calf, neck or back L drooling M difficulty in breathing N irritability O positive Babinski’s reflex P

64. The occurrence of polio may be prevented by POLIO IMMUNIZATION (VACCINE) The goal of treatment is to control symptoms while the infection runs its course Antibiotics may be used to treat urinary tract infections Medications such as bethanecol (may reduce urinary retention) analgesics (may reduce headache, muscle pain and spasms) Narcotics which are not usually given because they increase the risk of breathing difficulty. Moist heat (heating pads, warm towels, etc.) may also reduce muscle pain and spasms. Physical therapy, braces or corrective shoes, orthopedic surgery or similar interventions may eventually be necessary though to maximize the recovery of muscle strength and function #1 #2 #3 #4

65. The following are some of the complications that may develop from polio Spread of infection to other non-immune people Permanent muscle paralysis, disability or deformity Pulmonary edema (a condition characterized by fluid accumulation in the lungs caused by back pressure in the lung veins) Shock Complications of immobility and respiratory involvement such as: Aspiration Pneumonia Hypertension Urinary Tract Infections Kidney Stones A B C D E Paralytic Ileus

66. MYOCARDITIS (inflammation of the myocardium or the muscular tissue of the heart) COR PULMONAE (enlargement of the right ventricle that occurs because of pulmonary hypertension from lung disorders) F G

67. To avoid the diseases and the complications mentioned beforehand, be sure to consult your doctor if: Symptoms of poliomyelitis occur Someone close to you has developed poliomyelitis and you are not immunized against the disorder If your child’s polio immunization vaccine is not up-to-date #1 #2 #3

68. CARING FOR YOUR MUSCULAR SYSTEM Learning strand 2

69. Eat a lot of protein-rich foods such as soya beans, vegetables, meat and fish

70. Avoid activities that may cause injuries such as climbing on top of unstable furniture

71. Always wear or use protective equipment when doing something that might be dangerous

72. Exercise regularly to make your muscles strong

73. Keep things in order. Playthings left on the stairs or elsewhere may cause accidents

74. Rest every now and then while working to allow your muscles to relax

75. Lift weights properly. Avoid bending forward when carrying heavy loads

76. Always seek medical advice when an injury to muscles or tendons occurs, just to be sure

77. Maintain proper hygiene always

78. Let’s see what you have learned Fill in the blanks with the correct answers . ___________ 1. A tear or stretch in the muscle fiber or the tendon that connects a muscle to a bone ___________ 2. Occurs when one side of the joint is stronger than the other or the opposite muscle does not relax while the other contracts ___________ 3. Occurs when additional stress is put on a muscle and its connective tissue ___________ 4. A contraction of a muscle which is often painful ___________ 5. The result of minor local muscle contractions or the uncontrollable twitching of a single muscle group served by a single motor nerve fiber or filament ___________ 6. Commonly known as polio ___________ 7. Infections that may go unnoticed ___________ 8. A reflex where the great toe flexes toward the top of the foot and the other toes fan out when the sole of the foot is firmly stroked ___________ 9. A condition in which the blood pressure is abnormally high __________ 10. Help build muscles and are needed for them to function properly