Musculoskeletal Systems and Physiology of Exercise - Assignment Example

Musculoskeletal Systems and Physiology of Exercise Lecturer’s TAQ Question1- Explain what ossification is and what it involves. Ossification is a process by which the cartilages and mesenchymal cells are converted into bones during the process of development. There are two processes that are involved in bone deposition. These are endochondral and intramembranous ossification. Intramembranous ossification involves bone formation in which the mesenchyme are differentiated into the bone directly i.e. skull’s flat bones. The mesenchyme first differentiates into bone-forming cells referred to as osteoblasts that begin to deposit osteoid (Mackie et al. 2008). Afterwards, the osteoblasts will deposit calcium phosphate into the osteoid tissue that is converted into bone. On the other hand, endochondral ossification is a process of bone formation whereby the mesenchymal cells will give rise to cartilaginous models that will become ossified later and form bone and the cartilage will be gradually replaced by bones. Examples are skull’s basal bones, long bones of the limbs, ribs and vertebral column. There are two ossification centers the primary center that appears in the diaphysis and continues towards epiphysis and the secondary centers appearing in the epiphysis in most bones (Mackie et al. 2011). (Word count 170) Question 2- Describe the functions of the Skeleton. The human skeleton is composed of a package of bones, ligaments, tendons and cartilage, and it accounts for 20 percent of the body weight. Each bone of the human Skelton has blood vessels and bone marrow that is composed of fat cells, nerve cells and connective tissues that help in transporting blood throughout the body (Park 2009). The Skelton plays an important role of support as it holds the internal organs in place. An example is the skull that keeps the brain in a position. The Skelton also plays an essential role in the protection. It encases the body vital organs protecting them from damage. The human body is able to move because skeletal bones contain ligaments and tendons that perform certain movements when muscles relax and contract. The large bones making up the legs and arms allow humans to run, lift objects as well as walk. Bones also serve as a reservoir for essential minerals such as phosphorus, calcium that are important for various cellular activities throughout the body. As well, the production of blood cells occurs in the bone marrow that is within the cavities of certain bones. Fats are also stored in adipose cells of the yellow marrow to serve as energy reservoirs (Long & Ornitz 2013). (Word count 200) Question 3- identify the joints in the diagram and explain the reasons for your answers. The pivotal joint of the neck- it allows only rotary movements. It lacks access of viewing the node and allows rotation, flexion, retraction, protraction, extension, abduction and adduction movements. It allows ability of turning the head from side to side. Ball and socket joint- a joint where a ball shaped surface of a rounded bone fits into a cup like depression of another. The rounded head of the humerus rest on the socket of the shoulder blade allowing you to swing your hands. Hinge joint- it allows movements similar to the opening and closing of a hinged door. The elbow joint allows for the extension and flexion of the forearm relative to the upper arm as well as rotation of wrist and forearm. Ellipsoid joint- it allows the extending and bending movements rocking from side to side but rotation movements are limited. Saddle joint- bones in this joint can rock forth and back as well as from one side to another but have limited rotation. The joint in the thumbs is the only saddle joint. Gliding joint- bones move by gliding against each other. It occurs between surfaces of two bones that are flat held together by ligaments. (Word count 200) Question 4- describe the structure of a named synovial joint. The hip synovial joint The hip joint is a ball and socket that allows individuals to run, walk and jump. It is among bodys the most flexible joints. It allows a range of motions compared to other joints in the body with an exception of the shoulder joint. It is formed between the hipbone and the femur. It has a round cup structure on the hipbone referred to as the acetabulum that forms the socket for the joint. The femurs head is rounded in shape to constitute the ball of the joint (Yoon et al. 2011, 309). It is lined by hyaline cartilage lining the head of the femur and acetabulum to provide a smooth surface for gliding bone movement. The hyaline is also a shock absorber preventing the collision of bones during movement. The joint contains synovial membranes between the layers of the cartilage that are important in secreting the synovial fluid to lubricate the joint capsule. Tough ligaments preventing the joint dislocation surround the joint. Strong muscles around the joint preventing dislocation also hold it together. The ball and socket structure is important as it allows the femur to move through a 360-degree circle. The femur also has an ability of rotating around its axis in a 90-degree angle at the joint (Pacifici et al. 2005, 241). (Word count 210) TASK 2 Question 1- Explain the structure of a voluntary muscle using a fully labeled and referenced diagram. A skeletal muscle is a voluntary muscle also called a striated muscle as a result of its appearance. It contains dark and light bands that are visible under a light microscope. A single muscle is long and cylindrical in shape with many nuclei on the edges of the cell. The fibers of the muscle are packed into regular parallel bundles. The function of the muscle is allowing for movement of the skeleton under conscious control to include the movements of the fingers, toes, neck and limbs. It also allows for the movement of tissues of facial expression under conscious control to allow an individual to smile or frown (Gillies & Lieber 2011, 319). (Word count 130) Question 2- explain a tendon using a fully labeled and referenced diagram Tendons are connective tissues that attach to the muscle and bones in the body across joints to facilitate movement. It is made up of 80 percent type 1 collagen by weight. It is composed of six major areas with the smallest component being a collagen fibril made up of a group of collagen strands connected. The collagen fiber composed of collagen fibrils bound in a sheath of endotenon that provides stability. Fiber bundles represent the next level consisting of a group of collagen fibers bound together. The tendon is composed of fascicle that is the second largest component in its structure. The endotenon surrounding the fascicle are crimped in areas that come under very high stress. The tendon is made up of a group of fascicles that are joined together by an interior sheath of endotenon, as well as an exterior sheath of connective tissue (Kannus 2000, 313). (Word count- 150) Question 3- list the different types of muscle fibers There are three types of muscle fibers namely type I fibers, type II A fibers and type II B fibers. Question 4- how muscle fibers properties rely on aerobic and anaerobic Skeletal muscle fibers are made up of bundles of individual muscle fibers called myocytes. Each myocyte has myofibrils that are protein strands that hold into each other, shortens and cause muscle contraction. The muscle fibers are grouped into two main groups i.e. fast and slow twitch muscle fibers. These properties influence how muscles respond to physical activity and training with each type being unique to contract in a certain way. The human muscles contain a mixture of both slow and fast muscle fibers (Augusto et al. 2004, 92). In average, there are 50 percent slow twitch as well as 50 percent fast twitch fibers in a majority of muscles used for movement. Muscles that have slow twitch fibers are red in color as they contain many blood vessels. Slow twitch muscle fibers really on oxygenated blood as they utilize oxygen in energy production. On the other hand, the fast twitch fiber muscles do not utilize oxygen, so they do not require a rich blood supply (Schiaffino & Reggiani 2011, 1447). Type I fibers Also referred to as slow-twitch fibers or slow oxidative fibers and are red in color as a result of the large volumes of myoglobin presence as well oxygen and mitochondrion numbers. As a result, fact these fibers are very resistance to fatigue and are, therefore, capable of production of repeated low-level contractions to produce large ATP amounts through anaerobic metabolic. Due to this reason, muscles, which contain these fibers, are often postural muscles such as spine and neck muscles due to their endurance capabilities (Augusto et al. 2004, 94). Marathon runner’s athletes have a high number of this type of fiber obtained through training and genetics. Type II A fibers They are referred to fast oxidative fibers or fast twitch, are a hybrid of type II and type I muscle fibers. They have a great quantity of myoglobin and mitochondrial; therefore, their color is red. They utilize both aerobic and anaerobic metabolism; thus, they split and manufacture ATP very fast. For this reason, they produce strong and fast muscle contractions, and they are prone to fatigue than type I fibers. As a result of type resistance, type II B fibers, turn into type II A fibers due to an increase in the ability to utilize the oxidative cycle. Type II B fibers These fibers are referred to as fast glycolytic or fast twitch fibers and are white in color as a result of a low level of myoglobin as well as few mitochondria. As a result, they produce ATP at a slow rate through anaerobic metabolism breaking it down very fast. This leads to fast, short power bursts of power and rapid fatigue of these muscle fibers. This muscle fiber can be turned to type II A fibers by resistance training causing a positive change due to increased fatigue resistance of type II A fibers. The muscles are located in a large amount in the muscles of the arms (Wasicky et al. 2000, 986). (Word count 510) TASK 3 Exercise impact on the cardiovascular, muscular, respiratory and skeletal systems Response of the respiratory system to exercise During exercise, the respiratory system is responsible for oxygen transportation as well as carbon dioxide transportation between muscles and tissues. As a result of exercise, it increases its workload to meet the demands of the working body. The respiratory and cardiac system all work hard in hard. Additional oxygen is transported through the blood vessels to meet the increased oxygen demand. With an increased carbon dioxide and oxygen transportation, the rate of breathing also increases (McKenzie 2012, 381). The normal respiratory rate is about 14 beats per minute, but it increases to 32 beats per minute during exercise allowing more oxygen to reach the lungs and blood. Long-term consequences of exercise on the system include several physiological adaptations (Romer & Polkey 2008, 881). These adaptations, as a result, lead to an increase in the overall respiratory system efficiency in gathering, transporting and delivery of oxygen to the working muscles. Points on immediate effects of exercise There is an increased breathing rate There is an increase in the lungs tidal volume i.e. air breathed in and out of the lungs Long-term effects Increased strength of the diaphragm and intercostal muscles There is increased oxygen delivery and carbon dioxide removal from the body There is an increased number of alveoli There is an increase in the lungs vital capacity Response of the cardiovascular system to exercise Exercise places the cardiovascular system in an increased demand, as there is an increased oxygen demand by the body muscles. There is a production of more waste that is done faster. More nutrients are needed by the body and the temperature rises. In an effort to meeting the body demands, the cardiovascular system regulates these changes. During exercise, the heart rate increase and this happens even before the start of the exercise due to the body’s anticipatory response mediated through neurotransmitters release. The stroke volume will increase in proportion to the intensity of exercise. As well, the cardiac volume increase proportionally with the intensity of the exercise and so is the body’s blood flow. The blood pressure also changes, and the systolic pressure increases to over 200mmHg but the diastolic pressure can relatively remain unchanged regardless of the intensity of exercise. With time, the heart increases in size (Golbidi & Laher 2012, 12). Points on immediate effects of exercise The heart rate and stroke volume increases The blood temperature rises The blood vessels near the skin open to allow heat to be lost Blood is diverted to muscles from other systems. Long-term effects The heart muscle increases in size Cardiac output increases There is a reduced risk of heart diseases Increased volume of blood and red blood cells Capillary number in muscles increase Response of the musculoskeletal system to exercise The musculoskeletal system consists of bones, ligaments and cartilage that protect the bones from wear and tear (Panush & Lane 1994, 80). Exercise has a number of short and long-term effects on the system. Points on immediate effects of exercise There is a rise of the muscle temperature There is increased muscle contraction There is increased blood flow to muscles Long-term effects There is increased bone density and width Joint stability is enhanced The tendons, muscles and ligaments become stronger Endurance of muscles is enhanced There is hypertrophy of muscles (Word count 530) TASK 4 Describe and explain the physiological basis of osteoarthritis and cruciate knee injuries a) osteoarthritis Osteoporosis is also referred to, as a degenerative joint disorder is a condition that affects the entire joint to involve the ligament, cartilage, joint lining and underlying bone. As a result of the disease, there is a breakdown of tissue that leads to joint stiffness and pain. Most highly affected body joints include   the hip, knee hands, and spine joints. It is a common form of bodys  arthritis with its special cause remaining unknown but believed to be as a result of molecular and mechanical events that affect a joint (Goldring & Goldring 2007, 633). Either the condition is classified as idiopathic or secondary that is characterized progressive loss of hyaline cartilage in the joints that undergo bony changes. the most felt symptoms include pain in the joints, joint stiffness and swelling of the joints. The disease onset appears gradually but is often after the age of 40. Treatment of the disease entails improving joint function as well as relieving the symptoms (Hunter 2011, 815). The disease is not a single disease but results as a result of a variety of conditions that causes structural and functional failure of the joints in the body. It is the most predominant causes of chronic pain in the joints that affect even the nearby body muscles. There is a cartilage degeneration, that happens progressively, and the cartilage will try to repair itself, bone remodeling takes place, it hardens and there is a bone cyst formation (Hunter & Felson 2006, 640). The process takes place in several phases i.e. the stationary phase that involves the formation of osteophytes, as well as joint narrowing. Later on, the disease progresses further to obliteration of the joint space, subchondral cysts begin to appear that is an indication of the erosive stage of the disorder progression and the last stage of the disease progression involves bone remodeling and repair (Busija et al. 2010, 764). The disease is not hereditary but risk persons involve obesity persons as being overweight over a long time puts the joints under strain, occupational stress on joints and stress on the joints that is as a result of ageing or activity. Injuries to the joint lining as a result of past fracture accidents can also cause the disease. Treatment is by encouraging exercise and weight loss on the obese patients, relieving pain by applying heat or cold packs, massaging the muscles, non-steroidal inflammatory drugs and surgery can be done. (Word count 400) Cruciate knee injuries There are only two cruciate ligaments present around the knee at the back the posterior cruciate ligament and at the front the anterior cruciate knee ligament. These ligaments are very essential as they help in securing the knees stability in conjuction with other knee ligaments. However, the ligaments can get injuries but the injuries to the anterior ligament are very common than to the posterior cruciate ligament. The posterior ligament is more commonly damaged with connection to road accidents. On the other hand, a lesion or injury on the anterior cruciate ligament is often in sporting situations. If the anterior ligament is totally damaged and torn across, the knee becomes unstable (Hewett & Myer 2011, 161). Cruciate knee injuries are very common among athletes, as well as regular active people, and the injuries can be prevented. Anterior and posterior knee injuries account for about 40 percent of all knee injuries, therefore, proper care should be taken among the sports person to prevent their occurrence. This is achieved by maintaining a proper exercise as well as sports techniques that include not exceeding the body, properly warming up before a sporting activity and cooling down. Symptoms of cruciate knee injuries include pain and a click on the knee, difficulty in weight bearing and swelling of the knee (Toutoungi et al. 2000, 179). Lack of physical activity among the athletes and sports persons is associated with the occurrence of cruciate knee injuries. According to Trees et al. (2007), an important aspect of maintaining a knee away from injury is having strong hamstring and quadriceps muscles as they are essential for stabilizing the knee. Having a low hamstring to the quadriceps muscles has been associated with injury to the cruciate ligaments, and there is an 80 percent likelihood of injury occurrence. Exercises that are important in strengthening the quadriceps as well as hamstring muscles include leg lifts, knee extensions, leg curls and knee flexions. Exercises and stretch are thus important in the prevention of the knee injuries. Balancing exercise has been recommended as researchers have proven that people with poor balance are prone to more knee injuries than those with a good balance. This can be better achieved with the help of exercise training equipment such as Bosu balls and wobble boards. Another cruciate knee injury preventive measure is by wearing knee straps that are important in stabilizing the knee protecting it from injury especially among individuals playing demanding sports such as football (Gianotti et al. 2009, 626). (Word count 400) Bibliography Augusto, V. et al., 2004. 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