vania-janet/multiturn-rag-retrieval-data huggingface dataset:
White matter
White matter is the tissue through which messages pass between different areas of gray matter within the central nervous system . The white matter is white because of the fatty substance ( myelin ) that surrounds the nerve fibers ( axons ) . This myelin is found in almost all long nerve fibers , and acts as an electrical insulation . This is important because it allows the messages to pass quickly from place to place .
Heart
Heart tissue , like all cells in the body , needs to be supplied with oxygen , nutrients and a way of removing metabolic wastes . This is achieved by the coronary circulation , which includes arteries , veins , and lymphatic vessels . Blood flow through the coronary vessels occurs in peaks and troughs relating to the heart muscle 's relaxation or contraction .
Endocrine system
Secreted hormone From cells Effect Androgens ( chiefly testosterone ) Leydig cells Anabolic : growth of muscle mass and strength , increased bone density , growth and strength , Virilizing : maturation of sex organs , formation of scrotum , deepening of voice , growth of beard and axillary hair . Estradiol Sertoli cells Prevent apoptosis of germ cells Inhibin Sertoli cells Inhibit production of FSH Ovarian
Endocrine system
The endocrine system is the collection of glands of an organism that secrete hormones directly into the circulatory system to be carried towards distant target organs . The phenomenon of biochemical processes ' serving to regulate distant tissues by means of secretions directly into the circulatory system is called endocrine signaling . The major endocrine glands include the pineal gland , pituitary gland , pancreas , ovaries , testes , thyroid gland , parathyroid gland , and adrenal glands . The endocrine system is in contrast to the exocrine system , which secretes its hormones to the outside of the body using ducts . The endocrine system is an information signal system like the nervous system , yet its effects and mechanism are classifiably different . The endocrine system 's effects are slow to initiate , and prolonged in their response , lasting from a few hours up to weeks . The nervous system sends information very quickly , and responses are generally short lived . In vertebrates , the hypothalamus is the neural control center for all endocrine systems . The field of study dealing with the endocrine system and its disorders is endocrinology , a branch of internal medicine . Special features of endocrine glands are , in general , their ductless nature , their vascularity , and commonly the presence of intracellular vacuoles or granules that store their hormones . In contrast , exocrine glands , such as salivary glands , sweat glands , and glands within the gastrointestinal tract , tend to be much less vascular and have ducts or a hollow lumen .
Glycogen
Approximately 4 grams of glucose are present in the blood of humans at all times ; in fasted individuals , blood glucose is maintained constant at this level at the expense of glycogen stores in the liver and skeletal muscle . Glycogen stores in skeletal muscle serve as a form of energy storage for the muscle itself ; however , the breakdown of muscle glycogen impedes muscle glucose uptake , thereby increasing the amount of blood glucose available for use in other tissues . Liver glycogen stores serve as a store of glucose for use throughout the body , particularly the central nervous system . The human brain consumes approximately 60 % of blood glucose in fasted , sedentary individuals .
CCR5
This hypothesis was tested in an AIDS patient who had also developed myeloid leukemia , and was treated with chemotherapy to suppress the cancer . A bone marrow transplant containing stem cells from a matched donor was then used to restore the immune system . However , the transplant was performed from a donor with 2 copies of CCR5 - Δ32 mutation gene . After 600 days , the patient was healthy and had undetectable levels of HIV in the blood and in examined brain and rectal tissues . Before the transplant , low levels of HIV X4 , which does not use the CCR5 receptor , were also detected . Following the transplant , however , this type of HIV was not detected either , further baffling doctors . However , this is consistent with the observation that cells expressing the CCR5 - Δ32 variant protein lack both the CCR5 and CXCR4 receptors on their surfaces , thereby conferring resistance to a broad range of HIV variants including HIV X4 . After over six years , the patient has maintained the resistance to HIV and has been pronounced cured of the HIV infection .
Cellular waste product
H O also diffuses out of the cell into the blood stream , from where it is excreted in the form of perspiration , water vapor in breath , or urine from the kidneys . Water , along with some dissolved solutes , are removed from blood circulation in the nephrons of the kidney and eventually excreted as urine .
Stem cell
Fetal proper stem cells come from the tissue of the fetus proper , and are generally obtained after an abortion . These stem cells are not immortal but have a high level of division and are multipotent . Extraembryonic fetal stem cells come from extraembryonic membranes , and are generally not distinguished from adult stem cells . These stem cells are acquired after birth , they are not immortal but have a high level of cell division , and are pluripotent .
Endocrine system
In 1998 , skeletal muscle was identified as an endocrine organ due to its now well - established role in the secretion of myokines . The use of the term myokine to describe cytokines and other peptides produced by muscle as signalling molecules was proposed in 2003 .
Huntington's disease
HTT is expressed in all mammalian cells . The highest concentrations are found in the brain and testes , with moderate amounts in the liver , heart , and lungs . The function of HTT in humans is unclear . It interacts with proteins which are involved in transcription , cell signaling , and intracellular transporting . In animals genetically modified to exhibit HD , several functions of HTT have been found . In these animals , HTT is important for embryonic development , as its absence is related to embryonic death . Caspase , an enzyme which plays a role in catalyzing apoptosis , is thought to be activated by the mutated gene through damaging the ubiquitin - protease system . It also acts as an anti-apoptotic agent preventing programmed cell death and controls the production of brain - derived neurotrophic factor , a protein which protects neurons and regulates their creation during neurogenesis . HTT also facilitates vesicular transport and synaptic transmission and controls neuronal gene transcription . If the expression of HTT is increased and more HTT produced , brain cell survival is improved and the effects of mHTT are reduced , whereas when the expression of HTT is reduced , the resulting characteristics are more typical of the presence of mHTT . In humans the disruption of the normal gene does not cause the disease . It is thought that the disease is not caused by inadequate production of HTT , but by an increase in the toxic function of mHTT in the body .
Lead poisoning
Lead affects every one of the body 's organ systems , especially the nervous system , but also the bones and teeth , the kidneys , and the cardiovascular , immune , and reproductive systems . Hearing loss and tooth decay have been linked to lead exposure , as have cataracts . Intrauterine and neonatal lead exposure promote tooth decay . Aside from the developmental effects unique to young children , the health effects experienced by adults are similar to those in children , although the thresholds are generally higher . Kidneys
Vascular cambium
The vascular cambium ( also called main cambium , wood cambium , bifacial cambium ; plural cambia ) is a plant tissue located between the xylem and the phloem in the stems and roots of vascular plants . It is a cylinder of unspecialized meristem cells that divide to form secondary vascular tissues . It is the source of both secondary xylem growth inwards towards the pith , and secondary phloem growth outwards to the bark . Unlike the xylem and phloem , it does not transport water , minerals or food through the plant .
Bohr effect
The Bohr effect enables the body to adapt to changing conditions and makes it possible to supply extra oxygen to tissues that need it the most . For example , when muscles are undergoing strenuous activity , they require large amounts of oxygen to conduct cellular respiration , which generates CO ( and therefore HCO and H ) as byproducts . These waste products lower the pH of the blood , which increases oxygen delivery to the active muscles . Carbon dioxide is not the only molecule that can trigger the Bohr effect . If muscle cells are n't receiving enough oxygen for cellular respiration , they resort to lactic acid fermentation , which releases lactic acid as a byproduct . This increases the acidity of the blood far more than CO alone , which reflects the cells ' even greater need for oxygen . In fact , under anaerobic conditions , muscles generate lactic acid so quickly that pH of the blood passing through the muscles will drop to around 7.2 , which causes haemoglobin to begin releasing roughly 10 % more oxygen . The
Connective tissue
Tissue Purpose Components Location Collagenous fibers Bind bones and other tissues to each other Alpha polypeptide chains tendon , ligament , skin , cornea , cartilage , bone , blood vessels , gut , and intervertebral disc . Elastic fibers Allow organs like arteries and lungs to recoil Elastic microfibril and elastin extracellular matrix Reticular fibers Form a scaffolding for other cells Type III collagen liver , bone marrow , and lymphatic organs
Apoptosis
Apoptosis is a multi-step , multi-pathway cell - death programme that is inherent in every cell of the body . In cancer , the apoptosis cell - division ratio is altered . Cancer treatment by chemotherapy and irradiation kills target cells primarily by inducing apoptosis .
T-bone steak
To cut a T - bone from butchered cattle , a lumbar vertebra is sawn in half through the vertebral column . The downward prong of the ' T ' is a transverse process of the vertebra , and the flesh surrounding it is the spinal muscles . The small semicircle at the top of the ' T ' is half of the vertebral foramen .
Sciatic nerve
The sciatic nerve ( / saɪˈætɪk / ; also called ischiadic nerve , ischiatic nerve ) is a large nerve in humans and other animals . It begins in the lower back and runs through the buttock and down the lower limb . It is the longest and widest single nerve in the human body , going from the top of the leg to the foot on the posterior aspect . The sciatic nerve provides the connection to the nervous system for nearly the whole of the skin of the leg , the muscles of the back of the thigh , and those of the leg and foot . It is derived from spinal nerves L4 to S3 . It contains fibers from both the anterior and posterior divisions of the lumbosacral plexus .
Heart
Some congenital heart defects allow blood that is low in oxygen that would normally be returned to the lungs to instead be pumped back to the rest of the body . These are known as cyanotic congenital heart defects and are often more serious . Major congenital heart defects are often picked up in childhood , shortly after birth , or even before a child is born ( e.g. transposition of the great arteries ) , causing breathlessness and a lower rate of growth . More minor forms of congenital heart disease may remain undetected for many years and only reveal themselves in adult life ( e.g. atrial septal defect ) .
Spinal cord
Spinal cord The spinal cord ( in yellow ) connects the brain to nerves throughout the body . Details Part of Central nervous system Identifiers Latin medulla spinalis MeSH D013116 NeuroNames 22 TA A14. 1.02. 001 FMA 7647 Anatomical terminology ( edit on Wikidata )
Digestive enzyme
Parietal cells : Produce hydrochloric acid and intrinsic factor . Gastric chief cells : Produce pepsinogen . Chief cells are mainly found in the body of stomach , which is the middle or superior anatomic portion of the stomach . Mucous neck and pit cells : Produce mucin and bicarbonate to create a `` neutral zone '' to protect the stomach lining from the acid or irritants in the stomach chyme . G cells : Produce the hormone gastrin in response to distention of the stomach mucosa or protein , and stimulate parietal cells production of their secretion . G cells are located in the antrum of the stomach , which is the most inferior region of the stomach .
Human brain
The most common cancers in the brain come from elsewhere in the body -- most commonly the lung , breast and skin . Cancers of brain tissue can also occur , and originate from any tissue in and around the brain . Meningioma , cancer of the meninges around the brain , is more common than cancers of brain tissue . Cancers within the brain may cause symptoms related to their size or position , with symptoms including headache and nausea , or the gradual development of focal symptoms such as gradual difficulty seeing , swallowing , talking , or as a change of mood . Cancers are in general investigated through the use of CT scans and MRI scans . A variety of other tests including blood tests and lumbar puncture may be used to investigate for the cause of the cancer and evaluate the type and stage of the cancer . The corticosteroid dexamethasone is often given to decrease the swelling of brain tissue around a tumour . Surgery may be considered , however given the complex nature of many tumours or based on tumour stage or type , radiotherapy or chemotherapy may be considered more suitable .
Agranulocyte
Monocytes share the `` vacuum cleaner '' ( phagocytosis ) function of neutrophils , but are much longer lived as they have an additional role : they present pieces of pathogens to T cells so that the pathogens may be recognized again and killed , or so that an antibody response may be mounted . Monocytes are also known as macrophages after they migrate from the bloodstream and enter tissue .
Anemia
Heinz bodies form in the cytoplasm of RBCs and appear as small dark dots under the microscope . In animals , Heinz body anemia has many causes . It may be drug - induced , for example in cats and dogs by acetaminophen ( paracetamol ) , or may be caused by eating various plants or other substances :
Iron(II,III) oxide
Magnetite has been found as nano - crystals in magnetotactic bacteria ( 42 - 45 nm ) and in homing pigeon beak tissue
White blood cell
Monocytes , the largest type of WBCs , share the `` vacuum cleaner '' ( phagocytosis ) function of neutrophils , but are much longer lived as they have an extra role : they present pieces of pathogens to T cells so that the pathogens may be recognized again and killed . This causes an antibody response to be mounted . Monocytes eventually leave the bloodstream and become tissue macrophages , which remove dead cell debris as well as attack microorganisms . Neither dead cell debris nor attacking microorganisms can be dealt with effectively by the neutrophils . Unlike neutrophils , monocytes are able to replace their lysosomal contents and are thought to have a much longer active life . They have the kidney shaped nucleus and are typically agranulated . They also possess abundant cytoplasm .
Parasympathetic nervous system
The M1 muscarinic receptors ( CHRM1 ) are located in the neural system . The M2 muscarinic receptors ( CHRM2 ) are located in the heart , and act to bring the heart back to normal after the actions of the sympathetic nervous system : slowing down the heart rate , reducing contractile forces of the atrial cardiac muscle , and reducing conduction velocity of the sinoatrial node and atrioventricular node . They have a minimal effect on the contractile forces of the ventricular muscle due to sparse innervation of the ventricles from the parasympathetic nervous system . The M3 muscarinic receptors ( CHRM3 ) are located at many places in the body , such as the endothelial cells of blood vessels , as well as the lungs causing bronchoconstriction . The net effect of innervated M3 receptors on blood vessels is vasodilation , as acetylcholine causes endothelial cells to produce nitric oxide , which diffuses to smooth muscle and results in vasodilation . They are also in the smooth muscles of the gastrointestinal tract , which help in increasing intestinal motility and dilating sphincters . The M3 receptors are also located in many glands that help to stimulate secretion in salivary glands and other glands of the body . They are also located on the detrusor muscle and urothelium of the bladder , causing contraction . The M4 muscarinic receptors : Postganglionic cholinergic nerves , possible CNS effects The M5 muscarinic receptors : Possible effects on the CNS Types
Anemia
Macrocytic anemia can be further divided into `` megaloblastic anemia '' or `` nonmegaloblastic macrocytic anemia '' . The cause of megaloblastic anemia is primarily a failure of DNA synthesis with preserved RNA synthesis , which results in restricted cell division of the progenitor cells . The megaloblastic anemias often present with neutrophil hypersegmentation ( six to 10 lobes ) . The nonmegaloblastic macrocytic anemias have different etiologies ( i.e. unimpaired DNA globin synthesis , ) which occur , for example , in alcoholism . In addition to the nonspecific symptoms of anemia , specific features of vitamin B deficiency include peripheral neuropathy and subacute combined degeneration of the cord with resulting balance difficulties from posterior column spinal cord pathology . Other features may include a smooth , red tongue and glossitis . The treatment for vitamin B - deficient anemia was first devised by William Murphy , who bled dogs to make them anemic , and then fed them various substances to see what ( if anything ) would make them healthy again . He discovered that ingesting large amounts of liver seemed to cure the disease . George Minot and George Whipple then set about to isolate the curative substance chemically and ultimately were able to isolate the vitamin B from the liver . All three shared the 1934 Nobel Prize in Medicine . Normocytic
Finger
Sesamoid bones are small ossified nodes embedded in the tendons to provide extra leverage and reduce pressure on the underlying tissue . Many exist around the palm at the bases of the digits ; the exact number varies between different people .
Somatic cell nuclear transfer
Another application of SCNT stem cell research is using the patient specific stem cell lines to generate tissues or even organs for transplant into the specific patient . The resulting cells would be genetically identical to the somatic cell donor , thus avoiding any complications from immune system rejection .
Cell theory
The cell was first discovered by Robert Hooke in 1665 , which can be found to be described in his book Micrographia . In this book , he gave 60 ' observations ' in detail of various objects under a coarse , compound microscope . One observation was from very thin slices of bottle cork . Hooke discovered a multitude of tiny pores that he named `` cells '' . This came from the Latin word Cella , meaning ' a small room ' like monks lived in and also Cellulae , which meant the six sided cell of a honeycomb . However , Hooke did not know their real structure or function . What Hooke had thought were cells , were actually empty cell walls of plant tissues . With microscopes during this time having a low magnification , Hooke was unable to see that there were other internal components to the cells he was observing . Therefore , he did not think the `` cellulae '' were alive . His cell observations gave no indication of the nucleus and other organelles found in most living cells . In Micrographia , Hooke also observed mould , bluish in color , found on leather . After studying it under his microscope , he was unable to observe `` seeds '' that would have indicated how the mould was multiplying in quantity . This led to Hooke suggesting that spontaneous generation , from either natural or artificial heat , was the cause . Since this was an old Aristotelian theory still accepted at the time , others did not reject it and was not disproved until Leeuwenhoek later discovers generation is achieved otherwise .
Cell theory
Energy flow occurs within cells . Heredity information ( DNA ) is passed on from cell to cell . All cells have the same basic chemical composition .
Endocrine system
Secreted hormone Abbreviation From cells Effect Triiodothyronine T3 Thyroid epithelial cell ( More potent form of thyroid hormone ) Stimulates body oxygen and energy consumption , thereby increasing the basal metabolic rate Stimulates RNA polymerase I and II , thereby promoting protein synthesis Thyroxine ( tetraiodothyronine ) T4 Thyroid epithelial cell s ( Less active form of thyroid hormone ) ( Acts as a prohormone to triiodothyronine ) Stimulates body oxygen and energy consumption , thereby increasing the basal metabolic rate Stimulates RNA polymerase I and II , thereby promoting protein synthesis Calcitonin Parafollicular cell s Stimulates osteoblasts and thus bone construction Inhibits Ca release from bone , thereby reducing blood Ca
T cell
Double - positive thymocytes ( CD4 / CD8 ) move deep into the thymic cortex , where they are presented with self - antigens . These self - antigens are expressed by thymic cortical epithelial cells on MHC molecules on the surface of cortical epithelial cells . Only those thymocytes that interact with MHC - I or MHC - II appropriately ( i.e. , not too strongly or too weakly ) will receive a vital `` survival signal '' . All that can not ( i.e. , if they do not interact strongly enough , or if they bind too strongly ) will die by `` death by neglect '' ( no survival signal ) . This process ensures that the selected T - cells will have an MHC affinity that can serve useful functions in the body ( i.e. , the cells must be able to interact with MHC and peptide complexes to effect immune responses ) . The vast majority of all thymocytes end up dying during this process .
Spinal cord
Earlier findings by Viktor Hamburger and Rita Levi - Montalcini in the chick embryo have been confirmed by more recent studies which have demonstrated that the elimination of neuronal cells by programmed cell death ( PCD ) is necessary for the correct assembly of the nervous system .
Insulin
Insulin ( from Latin insula , island ) is a peptide hormone produced by beta cells of the pancreatic islets ; it is considered to be the main anabolic hormone of the body . It regulates the metabolism of carbohydrates , fats and protein by promoting the absorption of , especially glucose from the blood into liver , fat and skeletal muscle cells . In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats ( triglycerides ) via lipogenesis , or , in the case of the liver , into both . Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood . Circulating insulin also affects the synthesis of proteins in a wide variety of tissues . It is therefore an anabolic hormone , promoting the conversion of small molecules in the blood into large molecules inside the cells . Low insulin levels in the blood have the opposite effect by promoting widespread catabolism , especially of reserve body fat .
Human musculoskeletal 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 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 .