The muscular system is the anatomical system of a species that allows it to move. The muscular system in vertebrates is controlled through the nervous system, although some muscles (such as the cardiac muscle) can be completely autonomous. This article does not cite any references or sources. ... The nervous system is a highly specialized network whose principal components are nerves called neurons. ... For other uses of Muscles, see Muscles (disambiguation). ... Cardiac muscle is a type of involuntary striated muscle found within the heart. ...

Muscles

Main article: Muscle

There are three distinct types of muscles: skeletal muscles, cardiac muscles, and smooth muscles. For other uses of Muscles, see Muscles (disambiguation). ...

Skeletal muscle

Main article: Skeletal muscle

Skeletal muscle fibers are multinucleated, with the cell's nuclei located just beneath the plasma membrane. The cell comprises a series of striped or striated, thread-like myofibrils. Within each myofibril there are protein filaments that are anchored by dark Z lines. The fiber is one long continuous thread-like structure. The smallest cross section of skeletal muscle is called a sarcomere which is the functional unit within the cell. It extends from one Z line to the next attached Z line. The individual sarcomere has alternating thick myosin and thin actin protein filaments. Myosin forms the center or middle of each sarcomere. The exact center of the sarcomere is designated the M line. Thinner actin filaments form a zig zag pattern along the anchor points or Z line. A top-down view of skeletal muscle Skeletal muscle is a type of striated muscle, usually attached to the skeleton. ... Myofibrils (obsolete term: sarcostyles) are cylindrical organelles, found within muscle cells. ... Image of sarcomere A sarcomere is the basic unit of a cross striated muscles myofibril. ... Myosin is a motor protein filament found in muscle tissue. ... G-Actin (PDB code: 1j6z). ...

Upon stimulation by an action potential, skeletal muscles perform a coordinated contraction by shortening each sarcomere. The best proposed model for understanding contraction is the sliding filament model of muscle contraction. Actin and myosin fibers overlap in a contractile motion towards each other. Myosin filaments have club-shaped heads that project toward the actin filaments. A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ... The sliding filament mechanism is a process used by muscles to contract. ...

Larger structures along the myosin filament called myosin heads are used to provide attachment points on binding sites for the actin filaments. The myosin heads move in a coordinated style, they swivel toward the center of the sarcomere, detach and then reattach to the nearest active site of the actin filament. This is called a rachet type drive system. This process consumes large amounts of adenosine triphosphate (ATP). Myosin is a motor protein filament found in muscle tissue. ... Adenosine 5-triphosphate (ATP) is a multifunctional nucleotide that is most important as a molecular currency of intracellular energy transfer. ...

Energy for this comes from ATP, the energy source of the cell. ATP binds to the cross bridges between myosin heads and actin filaments. The release of energy powers the swiveling of the myosin head. Muscles store little ATP and so must continuously recycle the discharged adenosine diphosphate molecule (ADP) into ATP rapidly. Muscle tissue also contains a stored supply of a fast acting recharge chemical, creatine phosphate which can assist initially producing the rapid regeneration of ADP into ATP. Adenosine diphosphate, abbreviated ADP, is a nucleotide. ... Creatine, or creatine monohydrate [NH2-C(NH)-NCH2(COOH)-CH3], is a naturally occurring compound that helps to supply energy to the muscle cells. ...

Calcium ions are required for each cycle of the sarcomere. Calcium is released from the sarcoplasmic reticulum into the sarcomere when a muscle is stimulated to contract. This calcium uncovers the actin binding sites. When the muscle no longer needs to contract, the calcium ions are pumped from the sarcomere and back into storage in the sarcoplasmic reticulum. General Name, Symbol, Number calcium, Ca, 20 Chemical series alkaline earth metals Group, Period, Block 2, 4, s Appearance silvery white Atomic mass 40. ... The endoplasmic reticulum or ER is an organelle found in all eukaryotic cells that is an interconnected network of tubules, vesicles and cisternae that is responsible for several specialized functions: Protein translation, folding, and transport of proteins to be used in the cell membrane (e. ... Image of sarcomere A sarcomere is the basic unit of a cross striated muscles myofibril. ... The endoplasmic reticulum or ER is an organelle found in all eukaryotic cells that is an interconnected network of tubules, vesicles and cisternae that is responsible for several specialized functions: Protein translation, folding, and transport of proteins to be used in the cell membrane (e. ...

Anatomy

Main article: Table of muscles of the human body

There are approximately 639 skeletal muscles in the human body. This is a table of muscles of the human anatomy. ...

The following are some major muscles^[1] and their basic features:

The Gastrocnemius (pronounced ) muscle is a powerful superficial muscle that is in the back part of the lower leg (the calf). ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... The calcaneus is the large bone making up the heel of the human foot. ... The sural arteries (inferior muscular arteries) are two large branches, which are distributed to the Gastrocnemius, Soleus, and Plantaris. ... The Tibial Nerve The tibial nerve passes through the popliteal fossa to pass below the arch of soleus. ... Peronaeus longus and peronaeus brevis labeled at bottom left. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... For other uses, see Knee (disambiguation). ... The tibialis anterior is a muscle that spans the length of the tibia. ... The Tibialis posterior is the most central of all the leg muscles. ... This article is about the vertebrate bone. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ... For other uses, see Foot (disambiguation). ... Arteries of the lower limb - posterior view. ... The Tibial Nerve The tibial nerve passes through the popliteal fossa to pass below the arch of soleus. ... Tibialis anterior and posterior labeled at center top. ... In human and zoological anatomy (sometimes called zootomy), several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... For other uses, see Foot (disambiguation). ... For a review of anatomical terms, see Anatomical position and Anatomical terms of location. ... The tibialis anterior is a muscle that spans the length of the tibia. ... The soleus muscle and surrounding structures, from Grays Anatomy. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ... This article is about the vertebrate bone. ... The calcaneus is the large bone making up the heel of the human foot. ... The sural arteries (inferior muscular arteries) are two large branches, which are distributed to the Gastrocnemius, Soleus, and Plantaris. ... The Tibial Nerve The tibial nerve passes through the popliteal fossa to pass below the arch of soleus. ... Peronaeus longus and peronaeus brevis labeled at bottom left. ... The tibialis anterior is a muscle that spans the length of the tibia. ... The tibialis anterior is a muscle that spans the length of the tibia. ... This article is about the vertebrate bone. ... For other uses, see Foot (disambiguation). ... Anterior tibial artery and the muscles and bones of the leg - anterior view of right leg. ... The Deep fibular nerve (deep peroneal nerve) begins at the bifurcation of the common peroneal nerve, between the fibula and upper part of the Fibularis (Peronæus) longus, passes infero-medially, deep to Extensor digitorum longus, to the anterior surface of the interosseous membrane, and comes into relation with the... In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... Tibialis anterior and posterior labeled at center top. ... The muscle peroneus longus (also known as fibularis longus) is a superficial muscle in the human leg, and acts to evert and plantar flex the ankle. ... The Gastrocnemius (pronounced ) muscle is a powerful superficial muscle that is in the back part of the lower leg (the calf). ... The soleus muscle and surrounding structures, from Grays Anatomy. ... The Plantaris muscle is a muscle of the human body. ... The Tibialis posterior is the most central of all the leg muscles. ... The muscle peroneus longus (also known as fibularis longus) is a superficial muscle in the human leg, and acts to evert and plantar flex the ankle. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ... For other uses, see Foot (disambiguation). ... In anatomy, the fibular artery (also known as the peroneal artery) is a branch of posterior tibial artery that carries blood into the lateral compartment of the leg. ... The Superficial Fibular/Peroneal Nerve (musculocutaneous nerve of the leg) innervates the Peronei longus and brevis and the skin over the greater part of the dorsum of the foot. ... Peronaeus longus and peronaeus brevis labeled at bottom left. ... Peroneus longus and peroneus brevis labeled at center left. ... The tibialis anterior is a muscle that spans the length of the tibia. ... The Fibularis brevis (or Peronæus brevis) lies under cover of the Peronæus longus, and is a shorter and smaller muscle. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ... For other uses, see Foot (disambiguation). ... Peroneus longus and peroneus brevis labeled at center left. ... Arteries of the lower limb - posterior view. ... The Superficial Fibular/Peroneal Nerve (musculocutaneous nerve of the leg) innervates the Peronei longus and brevis and the skin over the greater part of the dorsum of the foot. ... The gluteus maximus is the largest and most superficial of the three gluteal muscles. ... The ilium of the pelvis is divisible into two parts, the body and the ala; the separation is indicated on the internal surface by a curved line, the arcuate line, and on the external surface by the margin of the acetabulum. ... For the record label, see Sacrum Torch. ... The Sacrotuberous Ligament (great or posterior sacrosciatic ligament) is situated at the lower and back part of the pelvis. ... The linea aspera is a ridge of roughened surface on the posterior aspect of the femur, to which are attached muscles and intermusclular septa. ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... Gluteal artery can refer to: Superior gluteal artery Inferior gluteal artery Category: ... The Superior Gluteal Nerve () arises from the dorsal divisions of the fourth and fifth lumbar and first sacral nerves: it leaves the pelvis through the greater sciatic foramen above the Piriformis, accompanied by the superior gluteal vessels, and divides into a superior and an inferior branch. ... External rotation (or lateral rotation) is rotation away from the center of the body. ... The leg extension is an isolation exercise. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... The Iliacus is a flat, triangular muscle, which fills the iliac fossa. ... This page is a candidate for speedy deletion. ... The psoas minor is a long, slender muscle that is placed (when present) in front of the psoas major muscle. ... The biceps femoris is a muscle of the posterior thigh. ... Human male pelvis, viewed from front Human female pelvis, viewed from front The pelvis is the bony structure located at the base of the spine (properly known as the caudal end). ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ... The inferior gluteal artery (sciatic artery), the larger of the two terminal branches of the anterior trunk of the hypogastric, is distributed chiefly to the buttock and back of the thigh. ... Arteries of the lower limb - posterior view. ... The Tibial Nerve The tibial nerve passes through the popliteal fossa to pass below the arch of soleus. ... The Common peroneal nerve is a branch of the Sciatic nerve. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... External rotation (or lateral rotation) is rotation away from the center of the body. ... An x-ray of a human knee Grays Fig. ... The leg extension is an isolation exercise. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... Quads redirects here. ... The Semitendinosus muscle is a muscle of the human body. ... Human male pelvis, viewed from front Human female pelvis, viewed from front The pelvis is the bony structure located at the base of the spine (properly known as the caudal end). ... This article is about the vertebrate bone. ... The inferior gluteal artery (sciatic artery), the larger of the two terminal branches of the anterior trunk of the hypogastric, is distributed chiefly to the buttock and back of the thigh. ... The sciatic nerve (also known as the ischiatic nerve) is a large nerve that runs down the lower limb. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... For other uses, see Knee (disambiguation). ... The leg extension is an isolation exercise. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... Quads redirects here. ... The Semimembranosus muscle is a muscle of the human body. ... Human male pelvis, viewed from front Human female pelvis, viewed from front The pelvis is the bony structure located at the base of the spine (properly known as the caudal end). ... This article is about the vertebrate bone. ... The profunda femoris (also known as the deep femoral artery, or the deep artery of the thigh) is a branch of the femoral artery that, as its name suggests, travels more deeply (posteriorly) than the rest of the femoral artery. ... Gluteal artery can refer to: Superior gluteal artery Inferior gluteal artery Category: ... The sciatic nerve (also known as the ischiatic nerve) is a large nerve that runs down the lower limb. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... The leg extension is an isolation exercise. ... For other uses, see Knee (disambiguation). ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... Quads redirects here. ... The ilium of the pelvis is divisible into two parts, the body and the ala; the separation is indicated on the internal surface by a curved line, the arcuate line, and on the external surface by the margin of the acetabulum. ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... The medial femoral circumflex artery (internal circumflex artery, medial circumflex femoral artery) is an artery in the upper thigh that helps supply blood to the neck of the femur. ... The iliolumbar artery, a branch of the posterior trunk of the hypogastric, turns upward behind the obturator nerve and the external iliac vessels, to the medial border of the Psoas major, behind which it divides into a lumbar and an iliac branch. ... The femoral nerve, the largest branch of the lumbar plexus, arises from the dorsal divisions of the second, third, and fourth lumbar nerves. ... The formation of the spinal nerve from the dorsal and ventral roots Grays Fig. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... The gluteus maximus is the largest of the gluteus muscles which are located in the buttock. ... The posterior fascial compartment of the thigh contains the knee flexors and hip extensors: biceps femoris semitendinosus semimembranosus The muscles here (except for the short head of the biceps femoris) are the hamstrings. ... Quads redirects here. ... The Rectus femoris muscle is a muscle of the human body. ... This is a table of muscles of the human anatomy. ... Femoral artery and its major branches - right thigh, anterior view. ... The femoral nerve, the largest branch of the lumbar plexus, arises from the dorsal divisions of the second, third, and fourth lumbar nerves. ... For other uses, see Knee (disambiguation). ... The leg extension is an isolation exercise. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... In human anatomy, a hamstring refers to one of the tendons that makes up the borders of the space behind the knee. ... In human anatomy, the Adductor muscles of the hip is a group of five muscles of the hip. ... The pubis, the anterior part of the hip bone, is divisible into a body, a superior and an inferior ramus. ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... This article is about the vertebrate bone. ... The Obturator Nerve arises from the ventral divisions of the second, third, and fourth lumbar nerves; the branch from the third is the largest, while that from the second is often very small. ... In anatomy and physiology, adduction is the moving of limbs towards the midline of the body. ... Bones of the Hip In anatomy, the hip is the bony projection of the femur, known as the greater trochanter, and the overlying muscle and fat. ... The levator scapulae is situated at the back and side of the neck. ... The vertebral column seen from the side Different regions (curvatures) of the vertebral column The vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... The Dorsal scapular artery (or descending scapular artery) is a blood vessel which supplies the latissimus dorsi, levator scapulae, rhomboids, and trapezius. ... The cervical nerves are the spinal nerves from the cervical vertebrae. ... The dorsal scapular nerve arises from the brachial plexus, specifically from spinal nerves C4 and C5. ... Elevation is the anatomical term of motion for movement in a superior direction. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... Glenoid fossa redirects here, for the other use of Glenoid fossa please see mandibular fossa. ... This article is about the human skeletal muscle. ... The vertebral column seen from the side Different regions (curvatures) of the vertebral column The vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. ... Collarbone and collar bone redirect here. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... In anatomy, the accessory nerve is a nerve that controls specific muscles of the neck. ... In anatomy, cervical is an adjective that has two meanings: of or pertaining to the neck. ... For other uses, see Nerve (disambiguation). ... Retraction is the anatomical term of motion for posterior movement of the arms at the shoulders. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... Serratus anterior Serratus anterior muscle is the surface of upper 9 ribs at side of chest - anterior aspect along entire length of medial border of scapula - (protraction) draws medial border of scapula away from vertebrae (upward rotation). ... The rectus abdominis muscle (commonly known as abs) is a paired muscle running vertically on each side of the anterior wall of the human abdomen (and in some other animals). ... The pubis, the anterior part of the hip bone, is divisible into a body, a superior and an inferior ramus. ... The costal cartilages are bars of hyaline cartilage which serve to prolong the ribs forward and contribute very materially to the elasticity of the walls of the thorax. ... This article is about the bones called ribs. ... The sternum (from Greek στέρνον, sternon, chest) or breastbone is a long, flat bone located in the center of the thorax (chest). ... Right inferior epigastric artery - view from inside of abdomen. ... The anterior divisions of the seventh, eighth, ninth, tenth, and eleventh thoracic intercostal nerves are continued anteriorly from the intercostal spaces into the abdominal wall; hence they are named thoraco-abdominal nerves (or thoracicoabdominal intercostal nerves). ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... The human torso Torso is an anatomical term for the greater part of the human body without the head and limbs. ... The lumbar vertebrae are the largest segments of the movable part of the vertebral column, and are characterized by the absence of the foramen transversarium within the transverse process, and by the absence of facets on the sides of the body. ... The Erector spinae (or Sacrospinalis in older texts), and its prolongations in the thoracic and cervical regions, lie in the groove on the side of the vertebral column. ... The transversus abdominis muscle, also known as the transversalis muscle and transverse abdominal muscle, is a muscle layer of the anterior and lateral abdominal wall which is just deep to (layered below) the internal oblique muscle. ... This article is about the bones called ribs. ... The ilium of the pelvis is divisible into two parts, the body and the ala; the separation is indicated on the internal surface by a curved line, the arcuate line, and on the external surface by the margin of the acetabulum. ... The pubis, the anterior part of the hip bone, is divisible into a body, a superior and an inferior ramus. ... The Iliohypogastric Nerve arises from the first lumbar nerve. ... The Ilioinguinal Nerve, smaller than the Iliohypogastric nerve, arises with it from the first lumbar nerve. ... The external oblique muscle (of the abdomen) (also external abdominal oblique muscle) is the largest and the most superficial (outermost) of the three flat muscles of the lateral anterior abdomen. ... The human rib cage. ... The crest of the ilium (or iliac crest) is convex in its general outline but is sinuously curved, being concave inward in front, concave outward behind. ... The inguinal ligament is a band running from the pubic tubercle to the anterior superior iliac spine. ... The thoracic spinal nerves T3 through T12. ... The anterior division of the twelfth thoracic nerve (subcostal nerve) is larger than the others; it runs along the lower border of the twelfth rib, often gives a communicating branch to the first lumbar nerve, and passes under the lateral lumbocostal arch. ... The human torso Torso is an anatomical term for the greater part of the human body without the head and limbs. ... The internal oblique muscle (of the abdomen) is the intermediate muscle of the abdomen, lying just underneath the external oblique and just above (superficial to) the transverse abdominal muscle. ... The inguinal ligament is a band running from the pubic tubercle to the anterior superior iliac spine. ... Human male pelvis, viewed from front Human female pelvis, viewed from front The pelvis is the bony structure located at the base of the spine (properly known as the caudal end). ... The thoracolumbar fascia (lumbodorsal fascia) is a deep investing membrane which covers the deep muscles of the back of the trunk. ... The linea alba is a fibrous structure that runs down the midline of the abdomen in humans and other animals. ... The sternum (from Greek στέρνον, sternon, chest) or breastbone is a long, flat bone located in the center of the thorax (chest). ... The Erector spinae (or Sacrospinalis in older texts), and its prolongations in the thoracic and cervical regions, lie in the groove on the side of the vertebral column. ... The thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. ... A typical thoracic vertebra The thoracic vertebrae (vertebrae thoracales) compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. ... In vertebrates, cervical vertebrae (singular: vertebra) are those vertebrae immediately behind (caudal to) the skull. ... The lateral sacral arteries arise from the posterior division of the hypogastric; there are usually two, a superior and an inferior. ... The posterior (or dorsal) branches (or divisions) of the spinal nerves are as a rule smaller than the anterior divisions. ... The vertebral column seen from the side Different regions (curvatures) of the vertebral column The vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. ... The rectus abdominis muscle (commonly known as abs) is a paired muscle running vertically on each side of the anterior wall of the human abdomen (and in some other animals). ... The Pectoralis major is a thick, fan-shaped muscle, situated at the upper front (anterior) of the chest wall. ... Collarbone and collar bone redirect here. ... The sternum (from Greek στέρνον, sternon, chest) or breastbone is a long, flat bone located in the center of the thorax (chest). ... The costal cartilages are bars of hyaline cartilage which serve to prolong the ribs forward and contribute very materially to the elasticity of the walls of the thorax. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... Axillary artery and its branches - anterior view of right upper limb and thorax. ... The Anterior Thoracic Nerves supply the Pectorales major and minor. ... Grays Fig. ... The term flex, when used by itself, can refer to: Flex Loader FLEX (operating system) Flex lexical analyser Flex machine Flex as colloquial for electrical cable or flexible electronics A flex point on a curve Flex (magazine) Macromedia Flex Flex is the name of a family of automatic test equipment... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... Anatomical planes in a human. ... Anatomical planes in a human Adduction is a movement which brings a limb - arm or leg - closer to the body in the sagittal plane. ... Internal rotation (or medial rotation) is rotation towards the center of the body. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... In human anatomy, the biceps brachii is a muscle located on the upper arm. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... The radius is the bone of the forearm that extends from the outside of your limb to your phlangx (lateral) of the elbow to the thumb side of the wrist. ... The brachial artery is the major blood vessel of the upper arm. ... The musculocutaneous nerve arises from the lateral cord of the brachial plexus, opposite the lower border of the Pectoralis minor, its fibers being derived from the fifth, sixth, and seventh cervical nerves. ... The term flex, when used by itself, can refer to: Flex Loader FLEX (operating system) Flex lexical analyser Flex machine Flex as colloquial for electrical cable or flexible electronics A flex point on a curve Flex (magazine) Macromedia Flex Flex is the name of a family of automatic test equipment... Elbow redirects here. ... Supine as an adjective generally refers to any upward-facing position. ... // The Human Forearm The forearm is the structure on the upper limb, between the elbow and the wrist. ... The triceps brachii muscle is a large three-headed skeletal muscle found in humans. ... The triceps brachii muscle is a large three-headed skeletal muscle found in humans. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... The ulna (Elbow Bone) [Figs. ... Right upper limb, anterior view, brachial artery and elbow. ... The radial nerve is a nerve in the human body, that supplies the arm, the forearm and the hand. ... Anatomical planes in a human. ... // The Human Forearm The forearm is the structure on the upper limb, between the elbow and the wrist. ... Anatomical planes in a human Adduction is a movement which brings a limb - arm or leg - closer to the body in the sagittal plane. ... This article is about the body part. ... In human anatomy, the biceps brachii is a muscle located on the upper arm. ... Brachialis is a flexor muscle in the upper arm. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... The ulna (Elbow Bone) [Figs. ... Arteries of the right forearm - anterior view. ... The musculocutaneous nerve arises from the lateral cord of the brachial plexus, opposite the lower border of the Pectoralis minor, its fibers being derived from the fifth, sixth, and seventh cervical nerves. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... This article is about the joint in the arm. ... The Pronator teres muscle is a muscle of the human body, in the forearm. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... The ulna (Elbow Bone) [Figs. ... The radius is the bone of the forearm that extends from the outside of your limb to your phlangx (lateral) of the elbow to the thumb side of the wrist. ... The ulnar artery is the main blood vessel, with oxygenated blood, of the medial aspect of the forearm. ... In human anatomy, the radial artery is the main blood vessel, with oxygenated blood, of the lateral aspect of the forearm. ... The median nerve is a nerve that runs down the arm and forearm. ... In human and zoological anatomy (sometimes called zootomy), several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... // The Human Forearm The forearm is the structure on the upper limb, between the elbow and the wrist. ... The term flex, when used by itself, can refer to: Flex Loader FLEX (operating system) Flex lexical analyser Flex machine Flex as colloquial for electrical cable or flexible electronics A flex point on a curve Flex (magazine) Macromedia Flex Flex is the name of a family of automatic test equipment... Elbow redirects here. ... The Supinator muscle is a muscle of the human body. ... Brachioradialis is a muscle located in the forearm, that acts to flex the forearm. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... The radius is the bone of the forearm that extends from the outside of your limb to your phlangx (lateral) of the elbow to the thumb side of the wrist. ... Arteries of the right forearm - anterior view. ... The radial nerve is a nerve in the human body, that supplies the arm, the forearm and the hand. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... // The Human Forearm The forearm is the structure on the upper limb, between the elbow and the wrist. ... Rhomboid muscles The rhomboid muscles, oftem simply called the rhomboids, are rhombus-shaped muscles associated with the scapula and are chiefly responsible for its retraction. ... The Nuchal ligament is a fibrous membrane, which, in the neck, represents the supraspinal ligaments of the lower vertebræ. It extends from the external occipital protuberance and median nuchal line to the spinous process of the seventh cervical vertebra. ... The spinous process of a vertebra is directed backward and downward from the junction of the laminae, and serves for the attachment of muscles and ligaments. ... A diagram of a thoracic vertebra. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... The Dorsal scapular artery (or descending scapular artery) is a blood vessel which supplies the latissimus dorsi, levator scapulae, rhomboids, and trapezius. ... The dorsal scapular nerve arises from the brachial plexus, specifically from spinal nerves C4 and C5. ... Retraction is the anatomical term of motion for posterior movement of the arms at the shoulders. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... Depression is the anatomical term of motion for movement in an inferior direction. ... Glenoid fossa redirects here, for the other use of Glenoid fossa please see mandibular fossa. ... The thoracic wall (or chest wall) is the boundary of the thoracic cavity. ... Serratus anterior Serratus anterior muscle is the surface of upper 9 ribs at side of chest - anterior aspect along entire length of medial border of scapula - (protraction) draws medial border of scapula away from vertebrae (upward rotation). ... In human anatomy, the deltoid muscle is the muscle forming the rounded contour of the shoulder. ... Collarbone and collar bone redirect here. ... The acromion process, or simply the acromion, is an anatomical feature on the scapula. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... The deltoid tuberosity is the region on the shaft of the humerus to which the the deltoid muscle attaches. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... The posterior humeral circumflex artery (posterior circumflex artery, posterior circumflex humeral artery) arises from the axillary artery at the lower border of the Subscapularis, and runs backward with the axillary nerve through the quadrangular space bounded by the Subscapularis and Teres minor above, the Teres major below, the long head... The axillary nerve is a nerve of the human body, that comes off the posterior cord of the brachial plexus at the level of the axilla (armpit) and carries nerve fibers from C5 and C6. ... This article is about the body part. ... Abduction, in functional anatomy, is a movement which draws a limb away from the median plane of the body. ... In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... The leg extension is an isolation exercise. ... Latissimus dorsi is a large flat muscle located on the back. ... The latissimus dorsi (plural: latissimi dorsi) is the large, flat, dorso-lateral muscle on the trunk, posterior to the arm, and partly covered by the spinotrapezius on its median dorsal region. ... The vertebral column seen from the side Different regions (curvatures) of the vertebral column The vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. ... The ilium of the pelvis is divisible into two parts, the body and the ala; the separation is indicated on the internal surface by a curved line, the arcuate line, and on the external surface by the margin of the acetabulum. ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ... Axillary artery and its branches - anterior view of right upper limb and thorax. ... The Dorsal scapular artery (or descending scapular artery) is a blood vessel which supplies the latissimus dorsi, levator scapulae, rhomboids, and trapezius. ... The Posterior cord is a division of the brachial plexus. ... A forelimb is an anterior limb on an animals body. ... In anatomy, the dorsum is the upper side of animals that typically run, fly or swim in a horizontal position, and the back side of animals (like humans) that walk upright. ... It has been suggested that Human Anatomical Terms be merged into this article or section. ... In human anatomy, the deltoid muscle is the muscle forming the rounded contour of the shoulder. ... This article is about the human skeletal muscle. ... The rotator cuff (rotor cuff) is an anatomical term given to the group of muscles and their tendons that act to stabilize the shoulder. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... The humerus is a long bone in the arm or fore-legs (animals) that runs from the shoulder to the elbow. ...

Aerobic and anaerobic muscle activity

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At rest, the body produces the majority of its ATP aerobically in the mitochondria without producing lactic acid or other fatiguing byproducts.^[2] During exercise, the method of ATP production varies depending on the fitness of the individual as well as the duration, and intensity of exercise. At lower activity levels, when exercise continues for a long duration (several minutes or longer), energy is produced aerobically by combining oxygen with carbohydrates and fats stored in the body. Activity that is higher in intensity, with possible duration decreasing as intensity increases, ATP production can switch to anaerobic pathways, such as the use of the creatine phosphate and the phosphagen system or anaerobic glycolysis. Aerobic ATP production is biochemically much slower and can only be used for long-duration, low intensity exercise, but produces no fatiguing waste products that can not be removed immediately from sarcomere and body and results in a much greater number of ATP molecules per fat or carbohydrate molecule. Aerobic training allows the oxygen delivery system to be more efficient, allowing aerobic metabolism to being more quickly.^[2] Anaerobic ATP production produces ATP much faster and allows near-maximal intensity exercise, but also produces significant amounts of lactic acid which render high intensity exercise unsustainable for greater than several minutes.^[2] The phosphagen system is also anaerobic, allows for the highest levels of exercise intensity, but intramuscular stores of phosphocreatine are very limited and can only provide energy for exercises lasting up to ten seconds. Recovery is very quick, with full creatine stores regenerated within five minutes.^[2] Image File history File links Question_book-3. ... Adenosine 5-triphosphate (ATP) is a multifunctional nucleotide that is most important as a molecular currency of intracellular energy transfer. ... In cell biology, a mitochondrion is an organelle found in the cells of most eukaryotes. ... For the production of milk by mammals, see Lactation. ... Lactose is a disaccharide found in milk. ... For other uses, see FAT. Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. ... Phosphocreatine, also known as creatine phosphate or PCr, is a phosphorylated creatine molecule that is an important energy store in skeletal muscle. ... Glycolysis is the sequence of reactions that converts glucose into pyruvate with the concomitant production of a relatively small amount of ATP. The word is derived from Greek γλυκύς (sweet) and λύσις (letting loose). ... Image of sarcomere A sarcomere is the basic unit of a cross striated muscles myofibril. ... For the production of milk by mammals, see Lactation. ... Phosphocreatine, also known as creatine phosphate or PCr, is a phosphorylated creatine molecule that is an important energy store in skeletal muscle. ...

Cardiac muscle

Main article: Heart muscle

Heart muscles are distinct from skeletal muscles because the muscle fibers are laterally connected to each other. Furthermore, just as with smooth muscles, they are not controlled by will. Heart muscles are controlled by the sinus node, which, in turn, is influenced by the autonomic nervous system. Myocardium is the muscular tissue of the heart. ... A muscle fiber (American usage) or muscle fibre (British usage) is a single cell of a muscle. ... The sinoatrial node (abbreviated SA node, also called the sinus node) is the impulse generating (pacemaker) tissue located in the right atrium of the heart. ... This article or section is in need of attention from an expert on the subject. ...

Smooth muscle

Main article: Smooth muscle

Smooth muscles are controlled directly by the autonomic nervous system. they are involuntary. (Involuntary means they are not controlled by conscious will.) Smooth muscle Layers of Esophageal Wall: 1. ... This article or section is in need of attention from an expert on the subject. ...

Control of muscle contraction

Neuromuscular junctions are the focal point where a motor neuron attaches to a muscle. Acetylcholine, (a neurotransmitter used in skeletal muscle contraction) is released from the axon terminal of the nerve cell when an action potential reaches the microscopic junction, called a synapse. A group of chemical messengers cross the synapse and stimulate the formation of electrical changes, which are produced in the muscle cell when the acetylcholine binds to receptors on its surface. Calcium is released from its storage area in the cell's sarcoplasmic reticulum. An impulse from a nerve cell causes calcium release and brings about a single, short muscle contraction called a muscle twitch. If there is a problem at the neuromuscular junction, a very prolonged contraction may occur, tetanus. Also, a loss of function at the junction can produce paralysis. A neuromuscular junction is the junction of the axon terminal of a motoneuron with the motor end plate, the highly-excitable region of muscle fiber plasma membrane responsible for initiation of action potentials across the muscles surface. ... In vertebrates, the term motor neuron (or motoneuron) classically applies to neurons located in the central nervous system (CNS) which project their axons outside the CNS and directly or indirectly control muscles. ... Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ... Illustration of the major elements in a prototypical synapse. ... A top-down view of skeletal muscle A muscle contraction (also known as a muscle twitch or simply twitch) occurs when a muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. ... Structure of a skeletal muscle A muscle contraction (also known as a muscle twitch or simply twitch) occurs when a muscle cell (called a muscle fiber) shortens. ... Tetanus is a medical condition that is characterized by a prolonged contraction of skeletal muscle fibers. ... Paralysed redirects here. ...

Skeletal muscles are organized into hundreds of motor units, each of which involves a motor neuron, attached by a series of thin finger-like structures called axon terminals. These attach to and control discrete bundles of muscle fibers. A coordinated and fine tuned response to a specific circumstance will involve controlling the precise number of motor units used. While individual muscle units contract as a unit, the entire muscle can contract on a predetermined basis due to the structure of the motor unit. Motor unit coordination, balance, and control frequently come under the direction of the cerebellum of the brain. This allows for complex muscular coordination with little conscious effort, such as when one drives a car without thinking about the process. A motor unit is a group of cells under the control of a single motor neuron; groups of motor units work together, as a single muscle. ... Illustration of the major elements in a prototypical synapse. ... The cerebellum (Latin: little brain) is a region of the brain that plays an important role in the integration of sensory perception and motor control. ...

See also

• Major systems of the human body

The major systems of the human body consist of: Circulatory system Digestive system Endocrine system Immune system Integumentary system Lymphatic system Muscular system Nervous system Reproductive system Respiratory system Skeletal system Urinary system Category: ...

Notes

Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 289th day of the year (290th in leap years) in the Gregorian calendar. ...

References

• Online Muscle Tutorial

External links

• GetBody Smart Muscle system tutorials and quizzes
• MedBio.info Use and formation of ATP in muscle