The contraction of the dash pulls the bones during movement

1 An Introduction to the Human Body • Introduction • 1.1 Overview of Anatomy and Physiology • 1.2 Structural Organization of the Human Body • 1.3 Functions of Human Life • 1.4 Requirements for Human Life • 1.5 Homeostasis • 1.6 Anatomical Terminology • 1.7 Medical Imaging • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 2 The Chemical Level of Organization • Introduction • 2.1 Elements and Atoms: The Building Blocks of Matter • 2.2 Chemical Bonds • 2.3 Chemical Reactions • 2.4 Inorganic Compounds Essential to Human Functioning • 2.5 Organic Compounds Essential to Human Functioning • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 3 The Cellular Level of Organization • Introduction • 3.1 The Cell Membrane • 3.2 The Cytoplasm and Cellular Organelles • 3.3 The Nucleus and DNA Replication • 3.4 Protein Synthesis • 3.5 Cell Growth and Division • 3.6 Cellular Differentiation • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 4 The Tissue Level of Organization • Introduction • 4.1 Types of Tissues • 4.2 Epithelial Tissue • 4.3 Connective Tissue Supports and Protects • 4.4 Muscle Tissue and Motion • 4.5 Nervous Tissue Mediates Perception and Response • 4.6 Tissue Injury and Aging • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 5 The Integumentary ...

• Classify the different types of muscle tissue • 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 19.33). Figure 19.33. 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 one nucleus in the center of the cell. (credit: modification of work by NCI, NIH; scale-bar data from Matt Russell) Skeletal Muscle Fiber Structure Each skeletal muscle fiber is a skeletal muscle cell. These cells are incredibly large, with diameters of up to 100 µm and lengths of up to 30 cm. The plasma membrane of a skeletal muscle fiber is called the sarcolemma. The sarcolemma is the site of action potential conduction, which triggers muscle contraction. Within each muscle fiber are myofibrils—long cylindrical structures that lie parallel to the muscle fiber. Myofibrils run the entire length of the muscle fiber, and because they are only approximately 1.2 µm in diameter, hundreds to thousands can be found inside one muscle fiber. They attach to the sarcolemma at th...

Learning Objectives • Define motor units and explain how the nervous system regulates graded muscle contractions (muscle tension) • Define and explain the physiological differences between fast-, slow-, and intermediate-twitch muscle fibers • Compare and contrast hydrostatic skeletons, exoskeletons, and endoskeletons Control of Muscle Tension Action potentials from efferent neurons initiate the formation of actin-myosin cross-bridges, leading to muscle contraction. These contractions extend from the muscle fiber through connective tissue to pull on bones, causing skeletal movement. The pull exerted by a muscle is called tension, and the amount of force created by this tension can vary. In other words, muscles contractions are graded ( the number of muscle fibers activated, and the frequency of neural stimulation to the muscle fibers. • Number of muscle fibers activated: How do you only activate only some of the muscle fibers in a muscle? Remember that a muscle fiber is the same thing as a muscle cell. A single efferent neuron typically controls multiple muscle fibers, and there are many many neurons that control different muscle fibers in a single muscle. A single efferent neuron and all of the muscle fibers that it controls is called a motor unit. Thus each muscle contains many motor units, and not all motor units are necessarily activated at the same time. The more motor units are active, the larger the number of muscle fibers that contract, and the greater the degree of...

More • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Q. Pick the correct description for what happens in the body when we do some physical activity like running or working with your hands. (a) Smooth muscles contract and pull the ligament to move the bones (b) Smooth muscles contract and pull the tendons to move the bones (c) Skeletal muscles contract and pull the ligament to move the bones (d) Skeletal muscles contract and pull the tendon to move the bones

[ "article:topic", "Muscle Contraction", "troponin", "tropomyosin", "sarcomere", "authorname:openstax", "actin", "acetylcholinesterase", "cardiac muscle", "motor end plate", "myofibril", "myofilament", "myosin", "sarcolemma", "skeletal muscle tissue", "smooth muscle", "thick filament", "thin filament", "showtoc:no", "transcluded:yes", "source[1]-bio-2027" ] \( \newcommand\) • • • • • • • • • Skills to Develop • Classify the different types of muscle tissue • 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 \(\PageIndex\): 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 one nucleus in the center of the cell. (credit: modification of work by NCI, NIH; scale-bar data from Matt Russell) Skeletal muscle tissue forms skeletal muscles, which attach to bones or skin and control locomotion and any movement that can be consciously controlled. Because it can be controlled by thought, skeletal muscle is also called voluntary muscle. Skeletal mu...

Explain the role of muscles in locomotion Muscle contraction occurs when sarcomeres shorten, as thick and thin filaments slide past each other, which is called the sliding filament model of muscle contraction. ATP provides the energy for cross-bridge formation and filament sliding. Regulatory proteins, such as troponin and tropomyosin, control cross-bridge formation. Excitation–contraction coupling transduces the electrical signal of the neuron, via acetylcholine, to an electrical signal on the muscle membrane, which initiates force production. The number of muscle fibers contracting determines how much force the whole muscle produces. Learning Objectives • Classify the different types of muscle tissue and fibers • Describe the processes of muscle contraction • Discuss why ATP is necessary for muscle movement • Identify the role of the brain in muscle movement • Discuss muscle tension and contraction Types of Muscle Tissue and Fibers 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 1). Figure 1. 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 bran...

1 An Introduction to the Human Body • Introduction • 1.1 Overview of Anatomy and Physiology • 1.2 Structural Organization of the Human Body • 1.3 Functions of Human Life • 1.4 Requirements for Human Life • 1.5 Homeostasis • 1.6 Anatomical Terminology • 1.7 Medical Imaging • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 2 The Chemical Level of Organization • Introduction • 2.1 Elements and Atoms: The Building Blocks of Matter • 2.2 Chemical Bonds • 2.3 Chemical Reactions • 2.4 Inorganic Compounds Essential to Human Functioning • 2.5 Organic Compounds Essential to Human Functioning • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 3 The Cellular Level of Organization • Introduction • 3.1 The Cell Membrane • 3.2 The Cytoplasm and Cellular Organelles • 3.3 The Nucleus and DNA Replication • 3.4 Protein Synthesis • 3.5 Cell Growth and Division • 3.6 Cellular Differentiation • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 4 The Tissue Level of Organization • Introduction • 4.1 Types of Tissues • 4.2 Epithelial Tissue • 4.3 Connective Tissue Supports and Protects • 4.4 Muscle Tissue and Motion • 4.5 Nervous Tissue Mediates Perception and Response • 4.6 Tissue Injury and Aging • Key Terms • Chapter Review • Interactive Link Questions • Review Questions • Critical Thinking Questions • 5 The Integumentary ...

Explain the role of muscles in locomotion Muscle contraction occurs when sarcomeres shorten, as thick and thin filaments slide past each other, which is called the sliding filament model of muscle contraction. ATP provides the energy for cross-bridge formation and filament sliding. Regulatory proteins, such as troponin and tropomyosin, control cross-bridge formation. Excitation–contraction coupling transduces the electrical signal of the neuron, via acetylcholine, to an electrical signal on the muscle membrane, which initiates force production. The number of muscle fibers contracting determines how much force the whole muscle produces. Learning Objectives • Classify the different types of muscle tissue and fibers • Describe the processes of muscle contraction • Discuss why ATP is necessary for muscle movement • Identify the role of the brain in muscle movement • Discuss muscle tension and contraction Types of Muscle Tissue and Fibers 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 1). Figure 1. 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 bran...

• Classify the different types of muscle tissue • 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 19.33). Figure 19.33. 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 one nucleus in the center of the cell. (credit: modification of work by NCI, NIH; scale-bar data from Matt Russell) Skeletal Muscle Fiber Structure Each skeletal muscle fiber is a skeletal muscle cell. These cells are incredibly large, with diameters of up to 100 µm and lengths of up to 30 cm. The plasma membrane of a skeletal muscle fiber is called the sarcolemma. The sarcolemma is the site of action potential conduction, which triggers muscle contraction. Within each muscle fiber are myofibrils—long cylindrical structures that lie parallel to the muscle fiber. Myofibrils run the entire length of the muscle fiber, and because they are only approximately 1.2 µm in diameter, hundreds to thousands can be found inside one muscle fiber. They attach to the sarcolemma at th...

Learning Objectives • Define motor units and explain how the nervous system regulates graded muscle contractions (muscle tension) • Define and explain the physiological differences between fast-, slow-, and intermediate-twitch muscle fibers • Compare and contrast hydrostatic skeletons, exoskeletons, and endoskeletons Control of Muscle Tension Action potentials from efferent neurons initiate the formation of actin-myosin cross-bridges, leading to muscle contraction. These contractions extend from the muscle fiber through connective tissue to pull on bones, causing skeletal movement. The pull exerted by a muscle is called tension, and the amount of force created by this tension can vary. In other words, muscles contractions are graded ( the number of muscle fibers activated, and the frequency of neural stimulation to the muscle fibers. • Number of muscle fibers activated: How do you only activate only some of the muscle fibers in a muscle? Remember that a muscle fiber is the same thing as a muscle cell. A single efferent neuron typically controls multiple muscle fibers, and there are many many neurons that control different muscle fibers in a single muscle. A single efferent neuron and all of the muscle fibers that it controls is called a motor unit. Thus each muscle contains many motor units, and not all motor units are necessarily activated at the same time. The more motor units are active, the larger the number of muscle fibers that contract, and the greater the degree of...