Muscle Tissue Overview and Structure

They maintain the alignment of thick and thin filaments, provide elasticity, and link myofibrils to the sarcolemma and extracellular matrix.

Myosin is shaped like a twisted golf club, functioning as a motor protein that converts ATP's energy into mechanical energy necessary for force production.

Tropomyosin covers the Actin binding sites during relaxation, while troponin binds calcium, causing tropomyosin to move and expose these binding sites for contraction.

<p>Titin anchors thick filaments to Z discs and M lines, helps sarcomeres return to resting length, and prevents overstretching.</p> Signup and view all the answers

<p>The Sliding Filament Mechanism describes how thick and thin filaments slide over one another, resulting in the shortening of the muscle during contraction.</p> Signup and view all the answers

<p>One binding site is for actin while the other is for ATP, both necessary for myosin to interact with actin and generate force during contraction.</p> Signup and view all the answers

<p>Myomesin forms the M line, which holds thick filaments in proper alignment within the sarcomere.</p> Signup and view all the answers

<p>Calcium binds to troponin, activating it and causing it to pull tropomyosin away, which exposes the actin binding sites for myosin.</p> Signup and view all the answers

<p>T tubules tunnel from the surface to the inner aspects of muscle fibers, allowing action potentials to propagate deep within the fiber.</p> Signup and view all the answers

<p>The sarcoplasmic reticulum encircles myofibrils and releases calcium ions when an action potential arrives, initiating muscle contraction.</p> Signup and view all the answers

<p>Sarcomeres are the basic functional units of muscle contraction, extending from one Z disc to the next and containing thick and thin filaments.</p> Signup and view all the answers

<p>Thick filaments are primarily composed of myosin, while thin filaments consist of actin, troponin, and tropomyosin.</p> Signup and view all the answers

<p>Z-discs separate one sarcomere from another and anchor the thin filaments.</p> Signup and view all the answers

<p>Contractile proteins generate force during muscle contraction.</p> Signup and view all the answers

<p>Regulatory proteins help switch contractile proteins on and off, regulating muscle contraction.</p> Signup and view all the answers

<p>The A band contains thick filaments, the I band contains thin filaments, and the H band contains thick filaments; the M line holds thick filaments together.</p> Signup and view all the answers

<p>Hemopoiesis</p> Signup and view all the answers

<p>Metaphysis</p> Signup and view all the answers

<p>Periosteum</p> Signup and view all the answers

<p>Osteoblasts</p> Signup and view all the answers

<p>Proliferation zone</p> Signup and view all the answers

<p>Skeletal muscle (voluntary), Cardiac muscle (involuntary), and Smooth muscle (involuntary).</p> Signup and view all the answers

<p>Epimysium is a dense connective tissue that covers the entire skeletal muscle, helping to bind muscle fibers together.</p> Signup and view all the answers

<p>Tendons connect muscles to bones, providing strength and stability to the musculoskeletal system.</p> Signup and view all the answers

<p>Muscle fibers are the cells of muscle tissue, arising from the fusion of myoblasts, and have multiple nuclei, which are crucial for muscle function and repair.</p> Signup and view all the answers

<p>The sarcolemma is the plasma membrane of muscle fibers, playing a key role in the regulation of ion exchange and muscle contraction.</p> Signup and view all the answers

<p>Fascicles are surrounded by a connective tissue called perimysium.</p> Signup and view all the answers

<p>Somatic motor neurons are responsible for innervating skeletal muscles, enabling voluntary movements.</p> Signup and view all the answers

<p>The reddish appearance of skeletal muscles is due to their high vascularization, which provides oxygen and nutrients.</p> Signup and view all the answers

<p>Myosin heads attach to and walk along the thin filaments, pulling them towards the M line.</p> Signup and view all the answers

<p>The primary function is maintaining posture and providing aerobic endurance.</p> Signup and view all the answers

<p>FG fibers have a low capacity for generating ATP, utilize anaerobic metabolism, and are suited for rapid, intense movements of short duration.</p> Signup and view all the answers

<p>Myofibrils consist of thick (myosin) and thin (actin, tropomyosin, troponin) filaments.</p> Signup and view all the answers

<p>FOG fibers have an intermediate capacity for ATP generation and utilize both aerobic and anaerobic metabolism.</p> Signup and view all the answers

<p>Troponin and tropomyosin are regulatory proteins that control the interaction between actin and myosin during muscle contraction.</p> Signup and view all the answers

<p>The lengths of thin and thick filaments do not change during muscle contraction.</p> Signup and view all the answers

<p>The three types are Slow Oxidative (SO), Fast Oxidative Glycolytic (FOG), and Fast Glycolytic (FG) fibers.</p> Signup and view all the answers