Why Are Muscles Joined To Bones

Skeletal Muscle Structure.The cells of skeletal muscles are long fiber-like structures. They contain many nuclei and are subdivided into smaller structures called myofibrils. Myofibrils are composed of 2 kinds of myofilaments. The thin filaments are made of 2 strands of the protein actin and one strand of a regulatory protein coiled together. The thick filaments are staggered arrays of myosin molecules.

to contract, which then allows body movements and functions? There are two types of muscles in

The fibers in both cells are striated, and the fibers are long and each muscle cell is fused to one another. This is why so many nuclei are included. Also, the fibers are almost threadlike, with dark and light colored striations.

Serves as the cell 's skeleton. It is an interior protein system that gives the cytoplasm quality and adaptability. The cytoskeleton of all cells is made of microfilaments, halfway fibers, and microtubules. Muscle cells contain these cytoskeletal parts in addition to thick fibers. The fibers and microtubules of the cytoskeleton frame a dynamic system whose ceaseless rearrangement influences cell shape and capacity.

Muscle fibres, as shown in Diagram 1, consist of myofibrils, which contain the proteins, actin and myosin, in specific arrangements . The diagram illustrates how a muscle is made up of many fascicles, which in turn are made up of many endomysiums, and within them, many muscle fibres. Each muscle fibre is made up of many myofibrils that consist of sarcomeres bound end on end . Actin is a thin filament, about 7nm in diameter, and myosin is a thick filament, about 15nm in diameter , both of which reside in the sarcomere. They are held together by transverse bands known as Z lines . Diagram 2 shows actin and myosin filaments within a sarcomere, and the Z lines that connect them.

Myofibrils are made up of long proteins that include myosin, titin, and actin while other proteins bind them together. These proteins are arranged into thin and thick filaments that are repetitive along the myofibril in sectors known as sarcomeres. The sliding of actin and myosin filaments along each other is when the muscle is contracting. Dark A-bands and light I-bands reappear along myofibrils. The alignment of myofibrils causes an appearance of the cell to look banded or striated. A myofibril is made up of lots of sarcomeres. As the sarcomeres contract individually the muscle cells and myofibrils shorten in length. The longitudinal section of skeletal muscle exhibits a unique pattern of alternating light and dark bands. The dark staining, A-bands possess a pale region in the middle called the H-zone. In the middle of the H-zone the M-line is found, that displays filamentous structures that can join the thick filaments. The light-staining bands also known as I-bands are divided by thin Z-line. These striated patterns appear because of the presence of myofibrils in the sarcoplasm (IUPUI, 2016).

Joints are the connecting points where two bones meet. They allow the human body to be flexible. Muscles are also necessary for movement. They pulls bones are allow them to move. Tendons attach muscles to bones while ligaments attach bones to bones. The central nervous system stimulates muscles to contract when they are stimulated by “messages”, or impulses, that are sent from motor nerves and the bursae are fluid filled sacs between joints that provide protection

The skeletal muscles are one of three major muscles types. As the name implies, these muscles are attached to bones by bundles o collagen fibers that are known as tendons. Skeletal muscles are made up of individual components that are known as muscle cells. These muscles have the appearance of long cylinders. The basic function is responsible for skeletal muscles to

muscles that move the joint by the tendons. Instead, ligament provide stability and join the knee

Muscles origin are always connected to the immovable bone, on the other side, the intersection is connected to the movable bone. Movement of the body occurs when muscles contract across joints and their attachments move toward the origin. Movements that are called Angular can increase or decrease the angle between the bones. Flexion can decrease the angle of the joint and can make the articulating bone come closer, an example could be nodding you head. An extension is the opposite and can make the angle larger.

Tendons attach muscle to bone. These strong yet stretchy bands of fibrous tissue join the skeletal muscles to the bones they move. Though alike to tendons, ligaments attach bone to bone and help to steady joints they surround. They are made up of long, stringy collagen fibers that make bands of strong, fibrous connective

It is important for a muscle to be attached to a fixed origin and a moving insertion because the immovable and movable bones attached on either side of the attached muscle, causing angular movements that change the angle of two bones. When the muscles contractacross the joints, they move towards the fixged origin by using the moving insertion. In order for the biceps to lift weights, they must use flexion and tension. Flexion describes the straightening of the muscle that increases the angle. Extension is when the joint moves in a posterior

Skeletal Muscle- These types of muscles are those of which attach to bones and have the main function of contracting to facilitate movement of our skeletons. They are also referred to as striated muscles due to their appearance. We have direct control over them through nervous impulses from our brains sending messages to the muscles. Contractions can vary to produce fast, powerful movements or small precise actions.

The skeletal system is made up of bones and joints. Bones are a dry dense tissue that is composed of calcium phosphorous and organic matter. The bones are protected and covered by a layer of fibrous connective tissue membrane called the periosteum (Brown, et al., 2015, p. 1547). There are two basic types of bone tissue: Compact Bone and Spongy Bone. Compact bones are dense smooth bones, while Spongy bones are composed of small needle-like pieces of bones and open space. Bones are then categorised according to the shape of the bone into four groups: long, short, flat and irregular. Long bones characteristically are typically longer then they are wide and generally have a shaft with heads at either ends e.g. the humerus. They are mainly compact bones. Short bones

A muscle is composed of numerous strands of tissue, referred to as fascicles. Each one of these fascicles are made up of bundles of muscle fibers (Lynn Hetzler). The muscle fibers are then made up of tens of thousands of myofibrils. Myofibrils are thread-like structures that are able to contract, relax, and stretch. Sacromeres, which are millions of thick and thin myofilaments laid end-to-end,