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37-600: The human musculoskeletal system (also known as the human locomotor system , and previously the activity system ) is an organ system that gives humans the ability to move using their muscular and skeletal systems . The musculoskeletal system provides form, support, stability, and movement to the body. The human musculoskeletal system is made up of the bones of the skeleton , muscles , cartilage , tendons , ligaments , joints , and other connective tissue that supports and binds tissues and organs together. The musculoskeletal system's primary functions include supporting

74-527: A microscope due to the components within their cells. Only skeletal and smooth muscles are part of the musculoskeletal system and only the muscles can move the body. Cardiac muscles are found in the heart and are used only to circulate blood ; like the smooth muscles, these muscles are not under conscious control. Skeletal muscles are attached to bones and arranged in opposing groups around joints . Muscles are innervated, whereby nervous signals are communicated by nerves , which conduct electrical currents from

111-448: A shoot system , and a root system . The shoot system consists stems, leaves, and the reproductive parts of the plant (flowers and fruits). The shoot system generally grows above ground, where it absorbs the light needed for photosynthesis . The root system, which supports the plants and absorbs water and minerals, is usually underground. Blood cell A blood cell (also called a hematopoietic cell , hemocyte , or hematocyte )

148-432: A decrease in function of platelets (thrombasthenia), or an increase in the number of platelets (thrombocytosis). There are disorders that reduce the number of platelets, such as heparin-induced thrombocytopenia (HIT) or thrombotic thrombocytopenic purpura (TTP), that typically cause thromboses, or clots, instead of bleeding. Platelets release a multitude of growth factors including platelet-derived growth factor (PDGF),

185-443: A microscope. Today, this process is generally automated by use of an automated analyzer, with only approximately 10-20% of samples now being examined manually. Abnormally high or low counts may indicate the presence of many forms of disease, and hence blood counts are amongst the most commonly performed blood tests in medicine, as they can provide an overview of a patient's general health status. In 1658 Dutch naturalist Jan Swammerdam

222-415: A nucleus. Red blood cells are much smaller than most other human cells. RBCs are formed in the red bone marrow from hematopoietic stem cells in a process known as erythropoiesis . In adults, about 2.4 million RBCs are produced each second. The normal RBCs count is 4.5 to 5 millions per cu.mm. RBCs have a lifespan of approximately 100-120 days. After they have completed their lifespan, they are removed from

259-448: A platelet is normally just 5 to 9 days. Platelets are a natural source of growth factors. They circulate in the blood of mammals and are involved in hemostasis, leading to the formation of blood clots. Platelets release thread-like fibers to form these clots. The normal range (99% of population analyzed) for platelets is 150,000 to 450,000 per cubic millimeter. If the number of platelets is too low, excessive bleeding can occur. However, if

296-663: A potent chemotactic agent, and TGF beta , which stimulates the deposition of extracellular matrix. Both of these growth factors have been shown to play a significant role in the repair and regeneration of connective tissues. Other healing-associated growth factors produced by platelets include basic fibroblast growth factor (bFGF), insulin-like growth factor 1 (IGF-1), platelet-derived epidermal growth factor, and vascular endothelial growth factor (VEGF). Local application of these factors in increased concentrations through platelet-rich plasma (PRP) has been used as an adjunct to wound healing for several decades. A complete blood count (CBC)

333-420: A role in the movement of bones. To allow motion, different bones are connected by joints. Cartilage prevents the bone ends from rubbing directly onto each other. Muscles contract to move the bone attached at the joint. There are, however, diseases and disorders that may adversely affect the function and overall effectiveness of the system. These diseases can be difficult to diagnose due to the close relation of

370-494: Is a cell produced through hematopoiesis and found mainly in the blood . Major types of blood cells include red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). Together, these three kinds of blood cells add up to a total 45% of the blood tissue by volume, with the remaining 55% of the volume composed of plasma , the liquid component of blood. Red blood cells or erythrocytes pors carry oxygen and collect carbon dioxide through

407-411: Is a complex structure with two distinct divisions; the axial skeleton , which includes the vertebral column , and the appendicular skeleton . The skeletal system serves as a framework for tissues and organs to attach themselves to. This system acts as a protective structure for vital organs. Major examples of this are the brain being protected by the skull and the lungs being protected by

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444-438: Is a joint that allows some movement, and false joints or synarthroses , joints that are immovable, that allow little or no movement and are predominantly fibrous . Synovial joints , joints that are not directly joined, are lubricated by a solution called synovial fluid that is produced by the synovial membranes . This fluid lowers the friction between the articular surfaces and is kept within an articular capsule , binding

481-405: Is a small fluid-filled sac made of white fibrous tissue and lined with synovial membrane . Bursa may also be formed by a synovial membrane that extends outside of the joint capsule . It provides a cushion between bones and tendons or muscles around a joint; bursa are filled with synovial fluid and are found around almost every major joint of the body. Because many other body systems, including

518-464: Is a test panel requested by a doctor or other medical professional that gives information about the cells in a patient's blood. A scientist or lab technician performs the requested testing and provides the requesting medical professional with the results of the CBC. In the past, counting the cells in a patient's blood was performed manually, by viewing a slide prepared with a sample of the patient's blood under

555-411: The central nervous system and cause the muscles to contract. In mammals , when a muscle contracts, a series of reactions occur. Muscle contraction is stimulated by the motor neuron sending a message to the muscles from the somatic nervous system . Depolarization of the motor neuron results in neurotransmitters being released from the nerve terminal . The space between the nerve terminal and

592-444: The immune system involved in defending the body against both infectious disease and foreign materials. They are produced and derived from multipotent cells in the bone marrow known as hematopoietic stem cells . Leukocytes are found throughout the body, including the blood and lymphatic system . There are a variety of types of white blood cells that serve specific roles in the human immune system. WBCs constitute approximately 1% of

629-409: The liver . Here all erythrocytes , platelets , and most leukocytes form in adults. From the red marrow, erythrocytes, platelets, and leukocytes migrate to the blood to do their special tasks. Another function of bones is the storage of certain minerals. Calcium and phosphorus are among the main minerals being stored. The importance of this storage "device" helps to regulate mineral balance in

666-453: The rib cage . Located in long bones are two distinctions of bone marrow (yellow and red). The yellow marrow has fatty connective tissue and is found in the marrow cavity . During starvation, the body uses the fat in yellow marrow for energy. The red marrow of some bones is an important site for blood cell production, approximately 2.6 million red blood cells per second in order to replace existing cells that have been destroyed by

703-419: The vascular , nervous , and integumentary systems , are interrelated, disorders of one of these systems may also affect the musculoskeletal system and complicate the diagnosis of the disorder's origin. Diseases of the musculoskeletal system mostly encompass functional disorders or motion discrepancies; the level of impairment depends specifically on the problem and its severity. In a study of hospitalizations in

740-944: The United States, the most common inpatient OR procedures in 2012 involved the musculoskeletal system: knee arthroplasty, laminectomy, hip replacement, and spinal fusion. Articular (of or pertaining to the joints) disorders are the most common. However, also among the diagnoses are: primary muscular diseases, neurologic (related to the medical science that deals with the nervous system and disorders affecting it) deficits, toxins, endocrine abnormalities, metabolic disorders, infectious diseases, blood and vascular disorders, and nutritional imbalances. Disorders of muscles from another body system can bring about irregularities such as: impairment of ocular motion and control, respiratory dysfunction, and bladder malfunction. Complete paralysis , paresis , or ataxia may be caused by primary muscular dysfunctions of infectious or toxic origin; however,

777-440: The blood volume. White blood cells are divided into granulocytes and agranulocytes , distinguished by the presence or absence of granules in the cytoplasm. Granulocytes include basophils , eosinophils , neutrophils , and mast cells . Agranulocytes include lymphocytes and monocytes . The condition of having too few white blood cells is leukopenia , while having too many is leukocytosis . There are individual terms for

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814-583: The bloodstream by the spleen . Mature red blood cells are unique among cells in the human body in that they lack a nucleus (although erythroblasts do have a nucleus). The condition of having too few red blood cells is known as anemia , while having too many is polycythemia . Erythrocyte sedimentation rate (ESR) is the rate at which RBCs sink to the bottom (when placed in a vertical column after adding an anticoagulant). Normal values of ESR are: • 3 to 5 mm per hour in males. • 4 to 7 mm per hour in females. White blood cells or leukocytes , are cells of

851-432: The bloodstream. When the fluctuation of minerals is high, these minerals are stored in the bone ; when it is low they will be withdrawn from the bone. There are three types of muscles— cardiac , skeletal , and smooth . Smooth muscles are used to control the flow of substances within the lumens of hollow organs , and are not consciously controlled . Skeletal and cardiac muscles have striations that are visible under

888-638: The body that are not organ systems—for example, the immune system protects the organism from infection, but it is not an organ system since it is not composed of organs. Some organs are in more than one system—for example, the nose is in the respiratory system and also serves as a sensory organ in the nervous system; the testes and ovaries are both part of the reproductive and endocrine systems. Other animals have similar organ systems to humans although simpler animals may have fewer organs in an organ system or even fewer organ systems. Plants have two major organs systems. Vascular plants have two distinct organ systems:

925-436: The body, allowing motion, and protecting vital organs. The skeletal portion of the system serves as the main storage system for calcium and phosphorus and contains critical components of the hematopoietic system . This system describes how bones are connected to other bones and muscle fibers via connective tissue such as tendons and ligaments. The bones provide stability to the body. Muscles keep bones in place and also play

962-628: The distal and proximal ends, and the tendon binds to the periosteum of individual bones at the muscle's origin and insertion. As muscles contract, tendons transmit the forces to the relatively rigid bones, pulling on them and causing movement. Tendons can stretch substantially, allowing them to function as springs during locomotion, thereby saving energy. The Joints are structures that connect individual bones and may allow bones to move against each other to cause movement. There are three divisions of joints, diarthroses which allow extensive mobility between two or more articular heads; amphiarthrosis , which

999-402: The human body There are 11 distinct organ systems in human beings, which form the basis of human anatomy and physiology . The 11 organ systems: the respiratory system, digestive and excretory system, circulatory system, urinary system, integumentary system, skeletal system, muscular system, endocrine system, lymphatic system, nervous system, and reproductive system. There are other systems in

1036-640: The joint with its taut tissue. A ligament is a small band of dense, white, fibrous elastic tissue . Ligaments connect the ends of bones together in order to form a joint. Most ligaments limit dislocation , or prevent certain movements that may cause breaks. Since they are only elastic they increasingly lengthen when under pressure. When this occurs the ligament may be susceptible to break resulting in an unstable joint. Ligaments may also restrict some actions: movements such as hyper extension and hyper flexion are restricted by ligaments to an extent. Also ligaments prevent certain directional movement. A bursa

1073-454: The lack or overabundance of specific types of white blood cells. The number of white blood cells in circulation is commonly increased in the incidence of infection . Many hematological cancers are based on the inappropriate production of white blood cells. Platelets , or thrombocytes , are very small, irregularly shaped clear cell fragments, 2–3 μm in diameter, which derive from fragmentation of megakaryocytes . The average lifespan of

1110-448: The method used to derive the count. While some consider certain structures to be a single bone with multiple parts, others may see it as a single part with multiple bones. There are five general classifications of bones. These are long bones , short bones , flat bones , irregular bones , and sesamoid bones . The human skeleton is composed of both fused and individual bones supported by ligaments , tendons , muscles and cartilage . It

1147-536: The muscle cell is called the neuromuscular junction . These neurotransmitters diffuse across the synapse and bind to specific receptor sites on the cell membrane of the muscle fiber . When enough receptors are stimulated, an action potential is generated and the permeability of the sarcolemma is altered. This process is known as initiation. A tendon is a tough, flexible band of fibrous connective tissue that connects muscles to bones. The extra-cellular connective tissue between muscle fibers binds to tendons at

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1184-481: The musculoskeletal system to other internal systems. The musculoskeletal system refers to the system having its muscles attached to an internal skeletal system and is necessary for humans to move to a more favorable position. Complex issues and injuries involving the musculoskeletal system are usually handled by a physiatrist (specialist in physical medicine and rehabilitation ) or an orthopaedic surgeon . The skeletal system serves many important functions; it provides

1221-433: The number of platelets is too high, blood clots can form thrombosis, which may obstruct blood vessels and result in such events as a stroke , myocardial infarction , pulmonary embolism , or blockage of blood vessels to other parts of the body, such as the extremities of the arms or legs. An abnormality or disease of the platelets is called a thrombocytopathy, which can be either a low number of platelets ( thrombocytopenia ),

1258-615: The primary disorder is usually related to the nervous system , with the muscular system acting as the effector organ, an organ capable of responding to a stimulus, especially a nerve impulse. One understated disorder that begins during pregnancy is pelvic girdle pain . It is complex, multi-factorial, and likely to be also represented by a series of sub-groups driven by pain varying from peripheral or central nervous system, altered laxity/stiffness of muscles, laxity to injury of tendinous/ligamentous structures to maladaptive body mechanics. Organ system Main article: List of systems of

1295-410: The shape and form for the body, support and protection, allows bodily movement, produces blood for the body, and stores minerals. The number of bones in the human skeletal system is a controversial topic. Humans are born with over 300 bones; however, many bones fuse together between birth and maturity. As a result, an average adult skeleton consists of 206 bones. The number of bones varies according to

1332-479: The use of hemoglobin . Hemoglobin is an iron -containing protein that gives red blood cells their color and facilitates transportation of oxygen from the lungs to tissues and carbon dioxide from tissues to the lungs to be exhaled. Red blood cells are the most abundant cell in the blood, accounting for about 40-45% of its volume. Red blood cells are circular, biconcave, disk-shaped and deformable to allow them to squeeze through narrow capillaries. They do not have

1369-448: Was the first person to observe red blood cells under a microscope, and in 1695, microscopist Antoni van Leeuwenhoek , also Dutch, was the first to draw an illustration of "red corpuscles", as they were called. No further blood cells were discovered until 1842 when French physician Alfred Donné discovered platelets. The following year leukocytes were first observed by Gabriel Andral , a French professor of medicine, and William Addison ,

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