All muscle cells contain striations.

Learn about the three types of muscle cells in the human body: cardiac, skeletal, and smooth. Skeletal muscle cells are striated, meaning they have stripes or bands, due to the arrangement of their proteins.

Skeletal Muscle Tissue. The striations are evidence of the myofilaments inside the muscle fibers. The position of the nuclei and vascularity are also signs of muscle tissue. You observe a tissue under a microscope. There appears to be a lumen on one side of the tissue. Lining this lumen, the cells seem to have long, fingerlike projections.In both skeletal and cardiac muscle, the actin and myosin proteins are arranged very regularly in the cytoplasm of individual muscle cells, which creates an alternating light …Figure 2. Smooth muscle cells do not have striations, while skeletal muscle cells do. Cardiac muscle cells have striations, but, unlike the multinucleate skeletal cells, they have only one nucleus. Cardiac muscle tissue also has intercalated discs, specialized regions running along the plasma membrane that join adjacent cardiac muscle cells and ...Muscles and Oxygen - Working muscles need oxygen in order to keep exercising. Learn how your blood gets oxygen to your muscles. Advertisement If you are going to be exercising for ...tissue consisting of cells that can contract. skeletal muscle fibers contain striations. what is the best description of a striation? alternating dark and light bands of protein filaments. the medical term polymyositis has a prefix that means. when a muscle contracts it.The term "muscle" covers a multitude of cell types, all specialized for contraction but in other respects dissimilar. As noted in Chapter 16, a contractile system involving actin and myosin is a basic feature of animal cells in general, but muscle cells have developed this apparatus to a high degree. Mammals possess four main categories of cells specialized for contraction: skeletal muscle ...

Structure of cardiac muscle fibers. A cardiac muscle cell (cardiomyocyte) is about 10-20 µm thick and 50-100 µm long. The cytoplasm contains myofibrils and densely packed mitochondria. The fibrils do not run strictly parallel to each other but rather branch in a complex pattern. The cardiac muscle cell has one centrally located nucleus. The ...Skeletal muscle is found throughout the body and functions to contract in response to a stimulus. Skeletal muscle serves many purposes, including producing movement, sustaining body posture and position, maintaining body temperature, storing nutrients, and stabilizing joints. In contrast to smooth and cardiac muscle contraction, …Gross and Microscopic Structure. Each skeletal muscle cell, also called a muscle fiber, develops from many individual embryonic myocytes that fuse into one long multi-nucleated skeletal muscle cell. The resultant fused muscle fiber is the length of the entire muscle. The longest muscle fiber in the body belongs to the sartorious muscle on the ...Explain the role of muscles in locomotion. Muscle cells are specialized for contraction. Muscles allow for motions such as walking, and they also facilitate bodily processes such as respiration and digestion. The body contains three types of muscle tissue: skeletal muscle, cardiac muscle, and smooth muscle (Figure 38.33). Figure 38.33 The body ...unlike skeletal muscles, smooth muscle cells have only one nucleus. true. both smooth muscles and cardiac muscles have striations. false. almost all of the ATP energy used up in muscle contraction is released in the form of heat. false. all motor neurons that stimulate a single muscle are referred to as motor units. false.Study with Quizlet and memorize flashcards containing terms like The ability of muscle cells to shorten is called _____, a property that allows muscle cells to cause body movement., Match each protein with the appropriate filament. (Thick Filament, Thin Filament, or Neither) -Myosin -Myosin Heads, Match each protein with the appropriate filament.

Cardiac Muscle Cells. use aerobic respiration almost exclusively. contain a large number of mitochondria to generate ATP. Smooth Muscle. is composed of short muscle cells that have fusiform shape- widest in the middle and tapered at each end. Smooth Muscle. have a single, centrally located nucleus. have both thick and thin filaments but they ...The fundamental repeat unit within muscle that is responsible for contraction is the sarcomere. The sarcomere consists of a bundle of myosin-containing thick filaments flanked and interdigitated with bundles of actin-containing thin filaments (Fig. 1). The striated appearance of muscle results from the alternation of thick-filament-containing (A-Band) and thin-filament-containing (I-band ...Correct Adipose tissue, bone, and blood (like all connective tissues) are derived from mesenchyme, an embryonic tissue. Also common to all connective tissues is the presence of cells and an extracellular matrix that consists of fibers bathed in ground substance. Chapter 4 True/False Question 1 Part A The shock-absorbing pads between the ...Why do skeletal muscle cells contain high numbers of mitochondria? Choose matching definition. to supply the ATP needed for skeletal muscle function. to give the muscle cell its striated appearance. to efficiently move digested food through the GI tract. so that the heart continues to beat. 4 of 20.A sarcomere (Greek σάρξ sarx "flesh", μέρος meros "part") is the smallest functional unit of striated muscle tissue. [1] It is the repeating unit between two Z-lines. Skeletal muscles are composed of tubular muscle cells (called muscle fibers or myofibers) which are formed during embryonic myogenesis. Muscle fibers contain numerous ...

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There are three varieties of human of muscles: skeletal, smooth, and cardiac. Skeletal striated muscle is the most abundant type (over 400 distinct muscles), is the only muscle under voluntary control, and in individuals with normal body mass index, represents approximately 40% of their body weight.[1] Smooth muscle manages contraction of non-voluntary muscles. The role of smooth muscle in ...Study with Quizlet and memorize flashcards containing terms like Cardiodynamics refers to the movements and forces generated during _____., Which layer of pericardium is equivalent to epicardium?, Which of the following is TRUE of cardiac muscle tissue? a. Cardiac muscle cells are larger than skeletal muscle cells. b. Cardiac muscle is not striated. c. Cardiac muscle cells have intercalated ...A muscle fiber is composed of many fibrils, which give the cell its striated appearance. The Sarcomere. ... Skeletal muscles contain connective tissue, blood vessels, and nerves. There are three layers of connective tissue: epimysium, perimysium, and endomysium. Skeletal muscle fibers are organized into groups called fascicles.There are six actin molecules around a single myosin molecules and there are more than 100,000 sarcomeres (one myosin and six actin make 1 sarcomere) in a single bicep muscle fibre (a …

Muscle cells contain organelles found in all cells, including nuclei, the endoplasmic reticulum, mitochondria and the Golgi apparatus. The amount and organization of organelles and structures is slightly different in muscle cells. ... At the tissue level, cardiac muscle is striated (or striped) since, like skeletal muscle, it has organized ...Smooth muscle cells contain many nuclei. Smooth muscle cells contain a network of T tubules., Layers of smooth muscle in the reproductive tract of the female are important in __________. movement of oocytes delivery of a newborn during parturition movement of sperm if present all of the listed functions and more.The cells that make up muscle tissue are called _____ myocytes. Match each type of muscle with the correct description of its structure. ... Select all correct descriptions of smooth muscle. fibers are uninucleated cells are spindle-shaped fibers are striated contains intercalated disks contraction is involuntary.A sarcomere is the basic unit of muscle tissue in both cardiac and skeletal muscle. Sarcomeres appear under the microscope as striations, with alternating dark and light bands. Sarcomeres are connected to a plasma membrane, called a sarcolemma, by T-tubules, which speed up the rate of depolarization within the sarcomere.Study with Quizlet and memorize flashcards containing terms like What is the ability of muscle cells to shorten called? a. elasticity b. conductivity c. excitability d. contractility, Skeletal muscle exhibits alternating light and dark bands called ______., which is true of involuntary muscle? a. it is never attached to bones b. it is sometimes attached to bones c. it is always attached to ...Figure 6.3.2 6.3. 2: Muscle type 1) Skeletal muscle cells are long tubular cells with striations (3) and multiple nuclei (4). The nuclei are embedded in the cell membrane (5) to be just inside the cell. This type of tissue occurs in the muscles that are attached to the skeleton.Science. Biology. Histology. Mastering Chapter 4 homework. All muscle cells contain striations. Click the card to flip 👆. False. (Smooth muscle cells do not contain …Both skeletal and cardiac muscles appear striated, or striped, because their cells are arranged in bundles. Smooth muscles are not striated because their cells are arranged in sheets instead of bundles. ... When cardiac muscle contracts, the heart beats and pumps blood. Cardiac muscle contains a great many mitochondria, which produce ATP for ...Bio exam multiple choice. A. Striated muscle fibres. Click the card to flip 👆. Which living structure is an exception to the cell theory? A. Striated muscle fibres. B. A single-celled alga carrying out all of the functions of life. C. The artificial synthesis of the organic molecule urea.intercalated discs and striations are both characteristics of. in connective tissue, role of elastic fiber is to. many-layered epithelium with cuboidal basal cells and flat cells at its surface would be classified as__. Don't know? 20 of 20. Quiz yourself with questions and answers for Mastering questions for test 2, so you can be ready for ...Study with Quizlet and memorize flashcards containing terms like All muscle cells are of what origin?, _______________contains bundles of very long, multinucleated cells with cross-striations. Their contraction is quick, forceful, and usually under voluntary control. A.Cardiac muscle B. Smooth Muscle C. Skeletal muscle, _____________also has cross-striations and is composed of elongated, often ...

Abstract. Many types of large cells have multiple nuclei. In skeletal muscle fibers, the nuclei are distributed along the cell to maximize their internuclear distances. This myonuclear positioning is crucial for cell function. Although microtubules, microtubule associated proteins, and motors have been implicated, mechanisms responsible for ...

Which type of muscle tissues is composed of cells that are striated in appearance and under voluntary control? ... Muscle fiber lack striations b. Cells have intercalated disks c. Also called isceral muscle d. Cells are spindle-shaped with a single nucleus e. Under voluntary control. a. Muscle fibers lack striations c. Also called viscernal ...Terms in this set (76) Study with Quizlet and memorize flashcards containing terms like Thick filaments:, What characteristic is not descriptive of cardiac muscle tissue? -intercalated discs -striations -located in heart -voluntary muscle contractions, Action potentials do not stay in one place, they are _____ throughout the entire sarcolemma ...Feb 15, 2024 · Learn about the three types of muscle cells in the human body: cardiac, skeletal, and smooth. Skeletal muscle cells are striated, meaning they have stripes or bands, due to the arrangement of their proteins. Striated skeletal muscles have characteristic cross-striations which are due to the regular arrangement of contractile elements, the sarcomeres. Striated skeletal …A) The outer surface of a muscle is enclosed by many layers of epidermis. B) All muscle cells in a muscle have the same origin and insertion. C) Fascicles of a muscle are surrounded by a thin sheath of hyaline cartilage. D) Connective tissues associated with the muscle converge to form a ligament at each end of the muscle.Myocytes, sometimes called muscle fibers, form the bulk of muscle tissue. They are bound together by perimysium, a sheath of connective tissue, into bundles called fascicles, which are in turn bundled together to form muscle tissue. Muscles are composed of long bundles of Myocytes (Muscle fibers). Myocytes contain thousands of myofibrils.Smooth-internal organs (involuntary) You are given a section of muscle to look at under the microscope. You note that the muscle cells exhibit cross striations. Therefore you know that this is: Skeletal. Muscles are connected to ___ by __. Muscles are composed of __ surrounded by__. -bones by tendons.synergists- contribute to an action by helping the agonist. Describe 3 aging-related changes in the muscular system. 1) Myoglobin, ATP, and Creatine decline.2) Gradually muscles become smaller and drier.3) By 80 half of muscle has atrophied. Explain the benefits of exercise for maintaining muscular health while aging.

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The sarcolemma is the cell membrane of a striated muscle cell. It forms a physical barrier against the external environment and also mediates signals between the exterior and the muscle cell. ... The sarcoplasm is the specialized cytoplasm of a muscle cell that contains the usual subcellular elements along with the Golgi apparatus, abundant ...Exercise and ATP - ATP is the source of energy that makes exercise work. Learn about the chemical processes that turn ATP into energy. Advertisement For your muscles -- in fact, fo...Each skeletal muscle cell, also called a muscle fiber, develops as many embryonic myocytes fused into one long, multi-nucleated skeletal muscle cell. These muscle fibers are bound together into bundles, or fascicles, and are supplied with a rich network of blood vessels and nerves. The fascicles are then bundled together to form the intact muscle.There are three major types of muscle, and their structure reflects their function. Skeletal and cardiac muscle cells are called striated muscle because of the very regular arrangement of their intracellular contractile units, sarcomeres, at the light microscope (LM) and electron microscope (EM) levels. This regular arrangement imparts a cross-striated (or striped) appearance.a. cardiac muscle cells have many nuclei. b. smooth muscle cells have t tubules. c. striated muscle cells are long and cylindrical with many nuclei. d. cardiac muscle cells are found in the heart and large blood vessels. Striated muscle cells are long and cylindrical with many nuclei. We have an expert-written solution to this problem!B) Muscle cell proteins. The cytoplasm of striated muscle cells contains fatty acid-binding proteins (FABPs) that transport long-chain unesterified fatty acids. C) Muscle cell thin filaments. The thin filament is the main site of Ca+2 regulation and is composed of four components in striated muscle: actin, TM and troponin (Tn) with its three ... Study with Quizlet and memorize flashcards containing terms like All muscle cells are of what origin?, _______________contains bundles of very long, multinucleated cells with cross-striations. Their contraction is quick, forceful, and usually under voluntary control. A.Cardiac muscle B. Smooth Muscle C. Skeletal muscle, _____________also has cross-striations and is composed of elongated, often ... The musculoskeletal system comprises one of the body's major tissue/organ systems. The three main types of muscle tissue are skeletal, cardiac, and smooth muscle groups.[1][2][3] Skeletal muscle attaches to the bone by tendons, and together they produce all body movements. The skeletal muscle fibers are crossed with a regular pattern of fine red and white lines, giving the muscle a distinctive ...Neurons are branched and faintly striated, and neuroglial cells are long slender projections. Neurons are only found in the spinal cord, and neuroglial cells are found only in the brain. Neurons transmit electrical impulses between/to other structures, and neuroglial cells are supporting cells. Neurons support and protect the neuroglial cells. skeletal muscle tissue. Muscle that is striated and voluntary. Smooth muscle tissue. Muscle that has no striations and is involuntary. neurons, glial cells, transmit nerve impulses, support neurons, dendrites, receive incoming, axon, carry outgoing. Nervous tissue consists of cells called _______ that receive, transmit, and process nerve impulses. Figure 6.2. The body contains three types of muscle tissue: skeletal muscle, smooth muscle, and cardiac muscle, visualized here using light microscopy. Smooth muscle cells are short, tapered at each end, and have only one plump nucleus in each. Cardiac muscle cells are branched and striated, but short. The cytoplasm may branch, and they have ... ….

Muscle tissue is characterized by properties that allow movement. Muscle cells are excitable; they respond to a stimulus. Study with Quizlet and memorize flashcards containing terms like All muscle cells contain striations., Smooth muscle _____., Under a microscope you observe a tissue that appears to have long fibers that appear striated. The nuclei are pushed off to the side of the fibers. The tissue looks very vascular. c) in the heart wall and lungs. d) in all passages that carry only. 1) the nerve signal ceases. 2) AChE breaks ACh down. 3) active transport pumps in the sarcoplasmic reticulum begin to pump calcium back into the cisternae. 4) calcium releases from troponin. 5) tropomyosin covers the myosin binding sites. place the steps of muscle relaxation in ...A. The autonomic nervous system innervates smooth muscle fibers. B. Smooth muscle fibers lack course connective tissue sheaths. C. Smooth muscle fibers lack T tubules. D. Troponin binds with calcium on the thin filaments of smooth muscle fibers. D.Nov 15, 2018 · One of the most iconic images in biology is the cross-striated appearance of a skeletal muscle fiber. The repeating band pattern shows that all of the sarcomeres are the same length. All of the A bands are the same length and are located in the middle of the sarcomeres. Furthermore, all of the myofibrils are transversely aligned across the muscle fiber. It has been known for 300 yr that ... Sha. 21, 1436 AH ... We're kicking off our exploration of muscles with a look at the complex and important relationship between actin and myosin.Smooth muscle (so-named because the cells do not have striations) is present in the walls of hollow organs like the urinary bladder, uterus, stomach, intestines, and in the walls of passageways, such as the arteries and veins of the circulatory system, and the tracts of the respiratory, urinary, and reproductive systems (Figure \(\PageIndex{1}\).a,b).Structure of cardiac muscle fibers. A cardiac muscle cell (cardiomyocyte) is about 10-20 µm thick and 50-100 µm long. The cytoplasm contains myofibrils and densely packed mitochondria. The fibrils do not run strictly parallel to each other but rather branch in a complex pattern. The cardiac muscle cell has one centrally located nucleus. The ...Skeletal Muscle Tissue. The striations are evidence of the myofilaments inside the muscle fibers. The position of the nuclei and vascularity are also signs of muscle tissue. You observe a tissue under a microscope. There appears to be a lumen on one side of the tissue. Lining this lumen, the cells seem to have long, fingerlike projections. All muscle cells contain striations., Abstract. There are three types of muscle in the body: skeletal (the muscles used to move the skeleton), cardiac (the muscle in the heart), and smooth (the muscle used for unconscious things like digestions and continence). Each has specialised cell adaptations. ANP and BNP are released from cardiac muscle when it is placed under stress., varying combinations, form all of the structures of ... Three types of muscle tissue. • Skeletal muscle ... • Contains elongated cells (fibers). • Fibers tied ..., Like skeletal muscle, it has striations ... of one large, interconnecting mass of muscle cells. ... between two cells contain adhesion junctions and gap junctions., Damage in a ligament results a sprain. Study with Quizlet and memorize flashcards containing terms like What are 2 other names for voluntary muscles?, Where are intercalated disks found?, Which type of muscle tissue contains striations? and more. , Cardiac muscle cells generally only contain one nucleus, located in the central region. They contain many mitochondria and myoglobin. Unlike skeletal muscle, cardiac muscle cells are unicellular. These cells are connected to each other by intercalated disks, which contain gap junctions and desmosomes. Striated versus smooth muscle, Expert-verified. Share. 1). True , striations are seen in skeletal muscles due to arrangement of thick myosin filament and thin actin filament in the myofibril. 2). False , T tubules are continuous with sarcolemma not sarcoplasmic reticulum. 3). Sarcomere , region between …. View the full answer., The statement "All muscle cells contain striations." is false. Muscle tissue can be categorized into three types: skeletal muscle, cardiac muscle, and smooth muscle. Skeletal and cardiac muscle cells do have striations due to the arrangement of their contractile proteins, namely actin and myosin, which create a striped appearance. In …, Myocytes, sometimes called muscle fibers, form the bulk of muscle tissue. They are bound together by perimysium, a sheath of connective tissue, into bundles called fascicles, which are in turn bundled together to form muscle tissue. Muscles are composed of long bundles of Myocytes (Muscle fibers). Myocytes contain thousands of myofibrils., HL084579/HL/NHLBI NIH HHS/United States. The striated muscle sarcomere contains, in addition to thin and thick filaments, a third myofilament comprised of titin. The extensible region of titin spans the I-band region of the sarcomere and develops passive force in stretched sarcomeres. This force positions the A-bands in the middle of the s …., The basic units of skeletal muscle are muscle cells that have many nuclei. These muscle cells also contain light and dark stripes called striations. The striations are a result of the orientation of the contractile proteins inside the cells. Skeletal muscle is therefore called striated muscle. Discuss further with Flexi. Ask your own question!, Muscle Tissue. (a) Skeletal muscle cells have prominent striation and nuclei on their periphery. (b) Smooth muscle cells have a single nucleus and no visible striations. (c) Cardiac muscle cells appear striated and have a single nucleus. From top, LM × 1600, LM × 1600, LM × 1600. (Micrographs provided by the Regents of University of Michigan ..., 8. ATP binds and causes the actin and myosin to dissociate from one another, after which it is hydrolyzed and myosin is recocked. The cycle repeats. 9. Sodium ions flood the sarcoplasm and initiate an action potential that spreads along the sarcolemma and into the muscle fiber along the T-tubules. 7, 9, 2, 6, 4, 1, 8, 5, 3., Abstract. Many types of large cells have multiple nuclei. In skeletal muscle fibers, the nuclei are distributed along the cell to maximize their internuclear distances. This myonuclear positioning is crucial for cell function. Although microtubules, microtubule associated proteins, and motors have been implicated, mechanisms responsible for ..., One of the most iconic images in biology is the cross-striated appearance of a skeletal muscle fiber. The repeating band pattern shows that all of the sarcomeres are the same length. All of the A bands are the same length and are located in the middle of the sarcomeres. Furthermore, all of the myofibrils are transversely aligned across the …, Each skeletal muscle cell, also called a muscle fiber, develops as many embryonic myocytes fused into one long, multi-nucleated skeletal muscle cell. These muscle fibers are bound together into bundles, or fascicles, and are supplied with a rich network of blood vessels and nerves. The fascicles are then bundled together to form the intact muscle., All muscle cells contain striations. True False. Question. All muscle cells contain striations. True False. Show More. 95. Solution. Expert Verified. 4.8 (172 votes) Stacey Rock Veteran · Tutor for 11 years. Answer <p> False</p>, Abstract. The striated muscle cell cytoskeleton is a multifunctional, dynamic, and complex structure that serves as a scaffold to maintain the structural integrity and architecture of the cell. However, it also functions as a platform for inter- and intracellular signaling, linking the contractile apparatus so that sarcomeres may function in ... , Muscle is a soft tissue, one of the four basic types of animal tissue.Muscle tissue gives skeletal muscles the ability to contract.Muscle is formed during embryonic development, in a process known as myogenesis.Muscle tissue contains special contractile proteins called actin and myosin which interact to cause movement. Among many other muscle proteins present are two regulatory proteins ..., Muscle: The Three Types of Muscle. Contractility is a fundamental property of cells and the majority of them contain essentially the same contractile machinery as that found in muscle cells. In muscle cells, however, a larger proportion of the cells' resources are given over to this function than in other cell types., muscle contraction. actin microfilaments and assciated proteins in muscle tissue produce forces for this. striated, cardiac and smooth. three types of muscle tissue. striated muscle tissue. contains bundles of very long, multinucleated cells with cross-striations. Their contraction is quick, forceful, and usually under voluntary control., True or False: All muscle cells contain striations. False. In adult humans, most cancers are carcinomas or adenocarcinomas. These include cancers of the skin, lung, colon, breast, and prostate. Which of the four basic tissue types is involved, and why? a. Connective tissue: it is found everywhere in the body, and is the only tissue common to ..., Similar to skeletal muscle, cardiac muscle is striated and organized into sarcomeres, possessing the same banding organization as skeletal muscle (Figure 1). However, cardiac muscle fibers are shorter than skeletal muscle fibers and usually contain only one nucleus, which is located in the central region of the cell., Figure 6.2. The body contains three types of muscle tissue: skeletal muscle, smooth muscle, and cardiac muscle, visualized here using light microscopy. Smooth muscle cells are short, tapered at each end, and have only one plump nucleus in each. Cardiac muscle cells are branched and striated, but short. The cytoplasm may branch, and they have ..., intercalated discs and striations are both characteristics of. in connective tissue, role of elastic fiber is to. many-layered epithelium with cuboidal basal cells and flat cells at its surface would be classified as__. Don't know? 20 of 20. Quiz yourself with questions and answers for Mastering questions for test 2, so you can be ready for ... , 1. Why is skeletal muscle referred to as striated muscle? Skeletal muscle is referred to as striated muscle because the myofibrils of each muscle cell are made up of a repeating pattern of cellular structures known as the sarcomere that, from a microscopic view, forms light and dark bands perpendicular to the long axis. 2., The actin and myosin proteins are arranged very regularly in the cytoplasm of individual muscle cells (referred to as fibers) in both skeletal muscle and cardiac muscle, which creates a pattern, or stripes, called striations. The striations are visible with a light microscope under high magnification (see Figure 10.2). , Why do skeletal muscle cells contain high numbers of mitochondria? Choose matching definition. to supply the ATP needed for skeletal muscle function. to give the muscle cell its striated appearance. to efficiently move digested food through the GI tract. so that the heart continues to beat. 4 of 20., Skeletal muscle fibers are classified into two types: type 1 and type 2. Type 2 is further broken down into subtypes. Type 1. These fibers utilize oxygen to generate energy for movement. Type 1 ..., 6 Muscle Introduction Although all cells are capable of some sort of movement, the dominant function of several cell types is to generate force through contraction. In these specialised contractile cells, movement is generated by interaction of the proteins actin and myosin (contractile proteins). Certain forms of contractile cell function as single-cell contractile units: • Myoepithelial…, These myoblasts asre located to the periphery of the myocyte and flattened so as not to impact myocyte contraction. Myocyte: Skeletal muscle cell: A skeletal muscle cell is surrounded by a plasma membrane called the sarcolemma with a cytoplasm called the sarcoplasm. A muscle fiber is composed of many myofibrils, packaged into orderly units., An Introduction to Muscle. Joseph A. Hill, Eric N. Olson, in Muscle, 2012 Smooth Muscle. Smooth muscle lacks the striations of skeletal and cardiac muscle because the actin and myosin filaments are not regularly arrayed along the length of the cell. Instead, the arrangement of filaments is less regimented and occurs as a spiral. Smooth muscle …, In both skeletal and cardiac muscle, the actin and myosin proteins are arranged very regularly in the cytoplasm of individual muscle cells, which creates an alternating light and dark striped pattern called striations. The striations are visible with a light microscope under high magnification (see Figure 24.1). Smooth muscle (named for it’s ..., Figure 24.3 – Muscle Fiber: A skeletal muscle fiber is surrounded by a plasma membrane called the sarcolemma, which contains sarcoplasm, the cytoplasm of muscle cells. A muscle fiber is composed of many myofibrils, which contain sarcomeres with light and dark regions that give the cell its striated appearance. The Sarcomere