Physiotherapy Unit 6- Muscles Muscles Muscles: Stru ure ity Muscles are essential to physical functions. To understand these^ functions, one needs to understand their structure. Muscles consist of soft connective tissue. They also consist of muscle fibers, or muscle cells. A bundle of fibers is a fascicle. A myofibril is a unit of muscle fiber. Each fiber contains proteins. Sarcomeres are other units of muscle. Each sarcomere contains long, fibrous proteins. Under a microscope, sarcomeres appear as light and dark bands. These bands slide back and forth as muscles contract. Muscles contract during physical movement. This occurs each time we stretch or flex. Elastic muscle fibers elongate or shorten during these contractions. After they relax, they resume their original position. _ Please discuss with your neighbour the following question: What is the structure of a muscle? 1 What is the structure of a muscle? A muscle consists of soft connective tissue. It is also made up of long, tubular proteins. These tubular proteins are called muscle fibers, or muscle cells. Please discuss with your neighbour following question: What is the function of muscles? 2 What is the function of muscles? Muscles have several functions: The most important function is to help the human body move. Muscles contract to produce movement. They also stretch and flex. Fascicle is a bundle of muscle Fascicle is a bundle of muscle fibers. Myofibril is a muscle fiber containing Myofibril is a muscle fiber containing proteins. Sarcomere: Long,.....proteins that slide back and forth. Appear as light or dark .... under a microscope. Sarcomere: Long, fibrious proteins that slide back and forth. Appear as light or dark bands under a microscope. Write a word or phrase that is similar in meaning to the underlined part: 1 After working out, Craig suffered from cramps in his soft, contracting tissues. (__s____) 2 Ava examined a slide of long proteins that slide past each other under a microscope. La____e___) 3 Actin, myosin, and titin are some of the proteins in a(n) rod-like unit of a muscle cell. L_o____i J 4 Bundles of muscle fiber help to transmit electrical signals in the heart. La______s) 5 Elongated, tubular cells help form skeletal and cardiac muscles. (____e)(_i___s) 1 After working out, Craig suffered from cramps in his soft, contracting tissues. (muscle) 2 Ava examined a slide of long proteins that slide past each other under a microscope. (sarcomeres) 3 Actin, myosin, and titin are some of the proteins in a rod-like unit of a muscle cell. (myofibril) 4 Bundles of muscle fiber help to transmit electrical signals in the heart. (Fascicles) 5 Elongated, tubular cells help form skeletal and cardiac muscles. (Muscle fibers) Fill in the blanks with the correct words from the word bank. BANK shorten flex elastic stretch contract 1 Muscles in order to produce movement in limbs. 2 After exercising. I to avoid cramping up. 3 Madeleine asked Steve to his arms so that she could see his biceps. 4 Muscle tissue is due to its ability to change size and shape. 5 Sarcomeres by one-third when actin and myosin slide past each other. 1 Muscles contract in order to produce movement in limbs. 2 After exercising, I stretch to avoid cramping up. 3 Madeleine asked Steve to flex his arms so that she could see his biceps. 4 Muscle tissue is elastic due to its ability to change size and shape. 5 Sarcomeres shorten by one-third when actin and myosin slide past each other. Listen to a conversation between two students. Mark the following statements as True or False. 1 Muscles are made of connective tissue True and muscle fibers. 2 Sarcomeres appear as light and dark bands True under a microscope. 3 A myofibril is a bundle of muscle fibers. False - a unit of muscle fibers that contain long proteins Listen again and complete the conversation Student 1: Let's review 1).........., shall we? Student 2: Sure. Why don't you just quiz me? I think that'll move things along more quickly. Student 1: Okay. First, what do muscles consist of? Student 2: 2).......... and muscle fibers. Student 1: Right. What is a 3) "....."? Student 2: A bundle of 4)........... Student 1: Very good. What is a 5) "....."? Student 2: A unit of muscle fibers that appear as light and dark bands under a microscope. Student 1: Actually, you described a 6).......A myofibril is a unit of muscle fibers that contain long proteins. Listen again and complete the conversation Student 1: Let's review muscle structure, shall we? Student 2: Sure. Why don't you just quiz me? I think that'll move things along more quickly. Student 1: Okay. First, what do muscles consist of? Student 2: Connective tissue and muscle fibers. Student 1: Right. What is a fascicle? Student 2: A bundle of muscle fibers. Student 1: Very good. What is a myofibril? Student 2: A unit of muscle fibers that appear as light and dark bands under a microscope. Student 1: Actually, you described a sarcomere. A myofibril is a unit of muscle fibers that contain long proteins. Speaking QComplete the conversation below based on Task 7, with the phrases given. Then, take roles and act it ou USE LANGUAGE SUCH AS: Let's review... shall we? What is a,,.? Actually, you described... Student A: You are a student. Talk to Student B about: • muscle structure • the definitions of muscle parts • the characteristics of muscle parts Student B: You are a student. Talk to Student A about the different parts of muscles and then characteristics. Let's review muscle structure again, shall we? Those are sarcomeres. What is a "myofibril"? First, what do muscles consist of? Actually, you described a fascicle. Let's review muscle structure again, shall we? Those are sarcomeres. What is a "myofibril"? First, what do muscles consist of? Actually, you described a fascicle. | A: B: Okay. Why don't you quiz me? That'll help us get done faster. A: All right. B: Connective tissue and muscle cells. A: That's right. B: A bundle of muscle fibers. A: like proteins. A myofibril is a unit of muscle fibers that consist of long, rod- B: Do they appear as light and dark bands under a microscope' A: No. Suggested answers: A: Leťs review muscle structure again, shall we? B: Okay. Why don't you quiz me? That'll help us get done faster. A: All right. First, what do muscles consist of? B: Connective tissue and muscle cells. A: That's right. What is a „myofibril"? B: A bundle of muscle fibers. A: Actually, you described a fascicle. A myofibril is a unit of muscle fibers that consist of long, rod-like proteins. B: Do they appear as light and dark bands under a microscope? A: No. Those are sarcomeres.