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Related to reticuloendothelial system: reticuloendothelial cells
The reticuloendothelial cells of the spleen possess the ability to dispose of disintegrated erythrocytes. They do not, however, destroy hemoglobin, which is liberated in the process.
The reticuloendothelial cells located in the blood cavities of the liver are called Kupffer cells. These cells, together with the cells of the general connective tissue and bone marrow, are capable of transforming into bile pigment the hemoglobin released by disintegrated erythrocytes.
The parts of a system can be referred to as its elements or components; the environment of the system is defined as all of the factors that affect the system and are affected by it. A living system is capable of taking in matter, energy, and information from its environment (input), processing them in some way, and returning matter, energy, and information to its environment as output.
An open system is one in which there is an exchange of matter, energy, and information with the environment; in a closed system there is no such exchange. A living system cannot survive without this exchange, but in order to survive it must maintain pattern and organization in the midst of constant change. Control of self-regulation of an open system is achieved by dynamic interactions among its elements or components. The result of self-regulation is referred to as the steady state; that is, a state of equilibrium. homeostasis is an assemblage of organic regulations that act to maintain steady states of a living organism.
A system can be divided hierarchically into subsystems, which can be further subdivided into sub-subsystems and components. A system and its environment could be considered as a unified whole for purposes of study, or a subsystem could be studied as a system. For example, the collection of glands in the endocrine system can be thought of as a system, each endocrine gland could be viewed as a system, or even specific cells of a single gland could be studied as a system. It is also possible to think of the human body as a living system and the endocrine system as a subsystem. The division of a system into a subsystem and its environment is dependent on the perspective chosen by the person studying a particular phenomenon.
re·tic·u·lo·en·do·the·li·al sys·tem (RES),
reticuloendothelial system (RES)
reticuloendothelial systemAn obsolescent term for the widespread system of protective MACROPHAGE (phagocyte) cells and endothelial cells found in the bone marrow, liver, spleen and elsewhere. The cells of the reticuloendothelial system include HISTIOCYTES, MONOCYTES, the KUPFFER CELLS of the liver and lung macrophages.
reticuloendothelial systemsee MONONUCLEAR PHAGOCYTE SYSTEM.
systemcomplex of functionally related anatomical structures
autonomic nervous system; ANS that part of the motor system investing smooth muscle of internal structures, e.g. organs, heart and vascular muscle, and gland cells; ANS is divided into sympathetic nervous system (SNS) and parasympathetic nervous system (paraSNS)
cardiovascular system heart, and all blood vessels (arteries, arterioles, capillaries, venules, veins)
central nervous system; CNS brain and spinal cord
circulatory system see system, vascular
digestive system alimentary tract from mouth to anus, and associated glands/organs
endocrine system all hormone-secreting tissues
extrapyramidal system; extrapyramidal motor system collective term denoting corpus striatum (basal ganglia), substantia nigra and subthalamic nucleus, plus descending connections to midbrain structures, and indirect connections to rhomboencephalic and spinal motor neurones; i.e. all central nervous system areas that affect motor function (motor cortex, and pyramidal [corticobulbar and corticospinal] tracts) but excluding upper motor neurones
limbic system array of brain structures adjacent to medial wall of cerebral hemispheres and their hypothalamic connections, influencing endocrine and autonomic function, motivational and mood states
lymphatic system lymphatic vessels and capillaries, lymph glands and lymphoid tissue
nervous system brain, spinal cord, all nerves and ganglia; i.e. collective term for central, peripheral and autonomic nervous system
neuromuscular system somatic musculature and associated motor neurones and nerves
parasympathetic nervous system; paraSNS part of ANS whose preganglionic motor neurones form the brainstem visceral motor ganglia and sacral lateral column ganglia
peripheral nervous system; PNS afferent peripheral sensory and efferent lower motor neurones that form the part of the nervous system outside the CNS
portal system blood vessels originating in one capillary bed and terminating in a second capillary bed without passing through the heart, e.g. pituitary hypophysis portal system (carrying hypothalamic trophic hormones to pituitary) or hepatic portal system (carrying nutrient-rich blood from gut wall to liver)
reticuloendothelial system range of macrophage-like cells within different tissues and organs, functioning as tissue-specific macrophages, e.g. Kupffer cells (in connective tissues and lymphatic structures), histiocytes (in connective tissues, e.g. dermis), alveolar phagocytes (in lung) and microglia (in nervous tissue)
sympathetic nervous system part of ANS whose preganglionic motor neurones lie within lateral column of thoracic, first and second lumbar segments of spinal cord
urinary system kidneys, ureters, bladder and urethra
vascular system; circulatory system cardiovascular and lymphatic systems
reticuloendothelial system (reˈ·ti·ky·lō·en·d·thēˑ·lē·l sisˑ·tm),