human anatomy and physiology muscular system pdf

Human Anatomy And Physiology Muscular System Pdf

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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.

The muscular system is the biological system of humans that produces movement. The muscular system, in vertebrates, is controlled through the nervous system, although some muscles, like cardiac muscle, can be completely autonomous. Muscle is contractile tissue and is derived from the mesodermal layer of embryonic germ cells. Its function is to produce force and cause motion, either locomotion or movement within internal organs. Much of muscle contraction occurs without conscious thought and is necessary for survival, like the contraction of the heart or peristalsis, which pushes food through the digestive system.

Human musculoskeletal system

The muscular system is the biological system of humans that produces movement. The muscular system, in vertebrates, is controlled through the nervous system, although some muscles, like cardiac muscle, can be completely autonomous. Muscle is contractile tissue and is derived from the mesodermal layer of embryonic germ cells. Its function is to produce force and cause motion, either locomotion or movement within internal organs.

Much of muscle contraction occurs without conscious thought and is necessary for survival, like the contraction of the heart or peristalsis, which pushes food through the digestive system. Voluntary muscle contraction is used to move the body and can be finely controlled, such as movements of the finger or gross movements that of the biceps and triceps. Muscle is composed of muscle cells sometimes known as "muscle fibers". Within the cells are myofibrils; myofibrils contain sarcomeres which are composed of actin and myosin.

Individual muscle cells are lined with endomysium. Muscle cells are bound together by perimysium into bundles called fascicles. These bundles are then grouped together to form muscle, and is lined by epimysium.

Muscle spindles are distributed throughout the muscles, and provide sensory feedback information to the central nervous system. Skeletal muscle, which involves muscles from the skeletal tissue, is arranged in discrete groups.

An example is the biceps brachii. It is connected by tendons to processes of the skeleton. In contrast, smooth muscle occurs at various scales in almost every organ, from the skin in which it controls erection of body hair to the blood vessels and digestive tract in which it controls the caliber of a lumen and peristalsis, respectively.

There are approximately skeletal muscles in the human body see list of muscles of the human body. Contrary to popular belief, the number of muscle fibers cannot be increased through exercise; instead the muscle cells simply get bigger. It is however believed that myofibrils have a limited capacity for growth through hypertrophy and will split if subject to increased demand.

There are three basic types of muscles in the body smooth, cardiac, and skeletal. While they differ in many regards, they all use actin sliding against myosin to create muscle contraction and relaxation. In skeletal muscle, contraction is stimulated at each cell by nervous impulses that releases acetylcholine at the neuromuscular junction, creating action potentials along the cell membrane.

All skeletal muscle and many smooth muscle contractions are stimulated by the binding of the neurotransmitter acetylcholine. Muscular activity accounts for most of the body's energy consumption. Glycogen can be rapidly converted to glucose when more energy is necessary. Cardiac and skeletal muscle are striated in that they contain sarcomere and are packed into highly-regular arrangements of bundles; smooth muscle has neither. Striated muscle is often used in short, intense bursts, whereas smooth muscle sustains longer or even near-permanent contractions.

For most muscles, contraction occurs as a result of conscious effort originating in the brain. The brain sends signals, in the form of action potentials, through the nervous system to the motor neuron that innervates the muscle fiber. However, some muscles such as the heart do not contract as a result of conscious effort. These are said to be autonomic. Also, it is not always necessary for the signals to originate from the brain.

Reflexes are fast, unconscious muscular reactions that occur due to unexpected physical stimuli. The action potentials for reflexes originate in the spinal cord instead of the brain. There are three general types of muscle contractions, skeletal muscle contractions, heart muscle contractions, and smooth muscle contractions. Summation of Muscle Contraction: It is the adding together of individual muscle twitches to make strong muscle movements.

When a muscle contracts, the actin is pulled along myosin toward the center of the sarcomere until the actin and myosin filaments are completely overlapped.

The H zone becomes smaller and smaller due to the increasing overlap of actin and myosin filaments, and the muscle shortens. Thus when the muscle is fully contracted, the H zone is no longer visible as in the bottom diagram, left. Note that the actin and myosin filaments themselves do not change length, but instead slide past each other. During cellular respiration the mitochondria, within skeletal muscle cells, convert glucose from the blood to carbon dioxide and water in the process of producing ATP see cell physiology.

ATP is needed for all muscular movement. When the need of ATP in the muscle is higher than the cells can produce with aerobic respiration, the cells will produce extra ATP in a process called anaerobic respiration.

The first step of aerobic respiration glycolysis produces two ATP per glucose molecule. When the rest of the aerobic respiration pathway is occupied the pyruvate molecule can be converted to lactic acid. This method produces much less ATP than the aerobic method, but it does it faster and allows the muscles to do a bit more than if they relied solely on ATP production from aerobic respiration.

The drawback to this method is that lactic acid accumulates and causes the muscles to fatigue. They will eventually stop contracting until the breakdown of lactic acid is sufficient to allow for movement once again. People experience this most noticeably when they repeatedly lift heavy things such as weights or sprint for a long distance.

Muscle soreness sometimes occurs after vigorous activity, and is often misunderstood by the general public to be the result of lactic acid buildup. This is a misconception because the muscle does fatigue from lactic acid buildup, but it does not stay in the muscle tissue long enough to cause tissue breakdown or soreness.

During heavy breathing, following exercise, the cells are converting the lactic acid either back into glucose or converting it to pyruvate and sending it through the additional steps of aerobic respiration. By the time a person is breathing normally again the lactic acid has been removed. The soreness is actually from small tears in the fibers themselves. After the fibers heal they will increase in size. The number of mitochondria will also increase if there is continued demand for additional ATP.

Hence, through exercise the muscles can increase in both strength and endurance. Another misconception is that as the muscle increases in size it also gains more fibers. This is not true. The fibers themselves increase in size rather than in quantity. The same holds true for adipose tissue--fat cells do not increase in number, but rather the amount of lipids oil in the cells increase. Muscle fibers are also genetically programmed to reach a certain size and stop growing from there, so after a while even the hardest working weightlifter will only reach a certain level of strength and endurance.

Some people will get around this by taking steroids. The artificial steroids cause all sorts of trouble for the person. They can cause the adrenal glands to stop producing corticosteroids and glucosteroids. This leads to the atrophy of the gland's medulla and causes permanent loss of the production of these hormones. The testicles may also atrophy in response to steroids. Eventually the testes will stop making testosterone and sperm, rendering the male infertile. One of the more serious problems associated with abnormal gain of muscle mass is heart failure.

While for most people gaining muscle and losing fat is desirable, a body builder is at risk of producing more muscle mass than the heart can handle. One pound of fat contains about 3.

Hence, additional muscle causes the heart to pump more blood. Some people that have too much muscle will be very strong but will not have a healthy aerobic endurance, in part because of the difficulty of providing oxygenated blood to so much tissue.

When Smooth and skeletal muscles go through multiple spasms it is referred either as seizure or convulsion. A strain occurs when a muscle or the tendon that attaches it to the bone is overstretched or torn.

Muscle strains are also called pulled muscles. Who gets it? Anyone can strain a muscle. However, people involved in sports or other forms of strenuous exercise are more likely to strain a muscle. What causes it? Muscles are bunches of fibers that can contract. Muscle strains usually occur during activities that require the muscle to tighten forcefully.

The muscle is strained either because it is not properly stretched, or warmed up, before the activity; it is too weak; or because the muscle is already injured and not allowed time to recover. So, many muscle strains occur during exercise or sports activities. They can also occur when lifting heavy objects. What are the symptoms? When a muscle is strained, it hurts and is difficult to move.

You may also feel a burning sensation in the area of the injured muscle, or feel as though something has "popped. A strained muscle might spasm, which means it contracts suddenly and involuntarily, causing severe pain.

How is it diagnosed? To diagnose a muscle strain, your doctor will examine the painful area, and ask how and when the injury happened. He or she may order other diagnostic tests, such as x-rays, to rule out any injury to the bone. Muscle strains are treated with rest, ice, compression, and elevation, or RICE. You will be told to rest the injured area to reduce pain and swelling. If the strain is in the leg or foot area, you may need to use crutches. Ice packs are recommended at regular intervals as recommended by your doctor over the first few days after the injury.

Ice causes the blood vessels to constrict, which reduces inflammation and pain. Anti-inflammatory medications might also be used to relieve pain. Compression and elevation help to reduce swelling.

Human Physiology/The Muscular System

This is a table of skeletal muscles of the human anatomy. There are around skeletal muscles [1] within the typical human body. Nevertheless, the exact number is difficult to define because different sources group muscles differently, e. The muscles of the human body can be categorized into a number of groups which include muscles relating to the head and neck, muscles of the torso or trunk, muscles of the upper limbs, and muscles of the lower limbs. The action refers to the action of each muscle from the standard anatomical position. In other positions, other actions may be performed. These muscles are described using anatomical terminology.

List of skeletal muscles of the human body

The human musculoskeletal system also known as the human locomotor system , and previously the activity system [1] is an organ system that gives humans the ability to move using their muscular and skeletal systems. The musculoskeletal system provides form, support, stability, and movement to the body. It is made up of the bones of the skeleton , muscles , cartilage , [2] tendons , ligaments , joints , and other connective tissue that supports and binds tissues and organs together. The musculoskeletal system's primary functions include supporting the body, allowing motion, and protecting vital organs.

The muscular system consists of various types of muscle that each play a crucial role in the function of the body. Muscles allow a person to move, speak, and chew. They control heartbeat, breathing, and digestion. Other seemingly unrelated functions, including temperature regulation and vision, also rely on the muscular system. The muscular system contains more than muscles that work together to enable the full functioning of the body.

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.

The musculoskeletal system review

The musculoskeletal system is an organ system that enables an organism to move, support itself, and maintain stability during locomotion. The musculoskeletal system also known as the locomotor system is an organ system that gives animals including humans the ability to move, using the muscular and skeletal systems. It provides form, support, stability, and movement to the body. Its primary functions include supporting the body, allowing motion, and protecting vital organs. The bones of the skeletal system provide stability to the body analogous to a reinforcement bar in concrete construction. Muscles keep bones in place and also play a role in their movement. To allow motion, different bones are connected by articulating joints, and cartilage prevents the bone ends from rubbing directly onto each other.

Muscle is a soft tissue found in most animals. Muscle cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture , locomotion , as well as movement of internal organs , such as the contraction of the heart and the movement of food through the digestive system via peristalsis. Muscle tissues are derived from the mesodermal layer of embryonic germ cells in a process known as myogenesis. There are three types of muscle, skeletal or striated, cardiac , and smooth. Muscle action can be classified as being either voluntary or involuntary.

Это чувство было очень приятно, ничто не должно было его омрачить. И его ничто не омрачало. Их отношения развивались медленно и романтично: встречи украдкой, если позволяли дела, долгие прогулки по университетскому городку, чашечка капуччино у Мерлутти поздно вечером, иногда лекции и концерты. Сьюзан вдруг поняла, что стала смеяться гораздо чаще, чем раньше. Казалось, не было на свете ничего, что Дэвид не мог бы обратить в шутку.


muscular systems of our bodies to work together Identify the major muscles associated with the main joints of the human body and anatomy and physiology.


BIOL 215/216 - Anatomy & Physiology I & II: Muscular System

4 comments

Laura L.

This site not only includes images, but also self-quizzing options for muscles as well.

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Emma B.

In this chapter we describe the gross anatomy of the muscular system and predict for the body on the basis of muscle physiology alone. Checkpoint. 4. Define The human body has approximately muscles. You do not.

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Fabienne A.

Bones are an important part of the musculoskeletal system.

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Terpnotibang

Cloud native java pdf github gone with the wind pdf

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