The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, distinguish them from the organism's own healthy tissue. In many species, the immune system can be classified into subsystems, such as the innate immune system versus the adaptive immune system, or humoral immunity versus cell-mediated immunity. In humans, the blood–brain barrier, blood–cerebrospinal fluid barrier, similar fluid–brain barriers separate the peripheral immune system from the neuroimmune system, which protects the brain. Pathogens can evolve and adapt, thereby avoid detection and neutralization by the immune system. Simple unicellular organisms such as bacteria possess a rudimentary immune system in the form of enzymes that protect against bacteriophage infections. Other basic immune mechanisms evolved in ancient eukaryotes and remain in their modern descendants, such as plants and invertebrates.
These mechanisms include phagocytosis, antimicrobial peptides called defensins, the complement system. Jawed vertebrates, including humans, have more sophisticated defense mechanisms, including the ability to adapt over time to recognize specific pathogens more efficiently. Adaptive immunity creates immunological memory after an initial response to a specific pathogen, leading to an enhanced response to subsequent encounters with that same pathogen; this process of acquired immunity is the basis of vaccination. Disorders of the immune system can result in inflammatory diseases and cancer. Immunodeficiency occurs when the immune system is less active than normal, resulting in recurring and life-threatening infections. In humans, immunodeficiency can either be the result of a genetic disease such as severe combined immunodeficiency, acquired conditions such as HIV/AIDS, or the use of immunosuppressive medication. In contrast, autoimmunity results from a hyperactive immune system attacking normal tissues as if they were foreign organisms.
Common autoimmune diseases include Hashimoto's thyroiditis, rheumatoid arthritis, diabetes mellitus type 1, systemic lupus erythematosus. Immunology covers the study of all aspects of the immune system; the immune system protects organisms from infection with layered defenses of increasing specificity. In simple terms, physical barriers prevent pathogens such as bacteria and viruses from entering the organism. If a pathogen breaches these barriers, the innate immune system provides an immediate, but non-specific response. Innate immune systems are found in all animals. If pathogens evade the innate response, vertebrates possess a second layer of protection, the adaptive immune system, activated by the innate response. Here, the immune system adapts its response during an infection to improve its recognition of the pathogen; this improved response is retained after the pathogen has been eliminated, in the form of an immunological memory, allows the adaptive immune system to mount faster and stronger attacks each time this pathogen is encountered.
Both innate and adaptive immunity depend on the ability of the immune system to distinguish between self and non-self molecules. In immunology, self molecules are those components of an organism's body that can be distinguished from foreign substances by the immune system. Conversely, non-self molecules are those recognized as foreign molecules. One class of non-self molecules are called antigens and are defined as substances that bind to specific immune receptors and elicit an immune response. Newborn infants have no prior exposure to microbes and are vulnerable to infection. Several layers of passive protection are provided by the mother. During pregnancy, a particular type of antibody, called IgG, is transported from mother to baby directly through the placenta, so human babies have high levels of antibodies at birth, with the same range of antigen specificities as their mother. Breast milk or colostrum contains antibodies that are transferred to the gut of the infant and protect against bacterial infections until the newborn can synthesize its own antibodies.
This is passive immunity because the fetus does not make any memory cells or antibodies—it only borrows them. This passive immunity is short-term, lasting from a few days up to several months. In medicine, protective passive immunity can be transferred artificially from one individual to another via antibody-rich serum. Microorganisms or toxins that enter an organism encounter the cells and mechanisms of the innate immune system; the innate response is triggered when microbes are identified by pattern recognition receptors, which recognize components that are conserved among broad groups of microorganisms, or when damaged, injured or stressed cells send out alarm signals, many of which are recognized by the same receptors as those that recognize pathogens. Innate immune defenses are non-specific, meaning these systems respond to pathogens in a generic way; this system does not confer long-lasting immunity against a pathogen. The innate immune system is the dominant system of host defense in most organisms.
Cells in innate immune system recognizes use pattern recognition receptors to recognize molecular structures that are produced by microbial pathogens. PRRs are germline-encoded host sensors, they are proteins expressed by cells of the innate immune system, such as dendritic cells, macrophages, m
Adaptive immune system
The adaptive immune system known as the acquired immune system or, more as the specific immune system, is a subsystem of the overall immune system, composed of specialized, systemic cells and processes that eliminate pathogens or prevent their growth. The acquired immune system is one of the two main immunity strategies found in vertebrates. Acquired immunity creates immunological memory after an initial response to a specific pathogen, leads to an enhanced response to subsequent encounters with that pathogen; this process of acquired immunity is the basis of vaccination. Like the innate system, the acquired system includes both humoral immunity components and cell-mediated immunity components; the term "adaptive" was first used by Robert Good in reference to antibody responses in frogs as a synonym for "acquired immune response" in 1964. Good acknowledged he used the terms as synonyms but explained only that he "preferred" to use the term "adaptive", he might have been thinking of the not implausible theory of antibody formation in which antibodies were plastic and could adapt themselves to the molecular shape of antigens, and/or to the concept of "adaptive enzymes" as described by Monod in bacteria, that is, enzymes whose expression could be induced by their substrates.
The phrase was used exclusively by Good and his students and a few other immunologists working with marginal organisms until the 1990's when it became used in tandem with the term "innate immunity" which became a popular subject after the discovery of the Toll receptor system in Drosophila, a marginal organism for the study of immunology. The term "adaptive" as used in immunology is problematic as acquired immune responses can be both adaptive and maladaptive in the physiological sense. Indeed, both acquired and innate immune responses can be both adaptive and maladaptive in the evolutionary sense. Most textbooks today, following the early use by Janeway, use "adaptive" exclusively and noting in glossaries that the term is synonymous with "acquired"; the classic sense of "acquired immunity" came to mean, since Tonegawas's discovery, "antigen-specific immunity mediated by somatic gene rearrangements that create clone-defining antigen receptors". In the last decade, the term "adaptive" has been applied to another class of immune response not so-far associated with somatic gene rearrangements.
These include expansion of natural killer cells with so-far unexplained specificity for antigens, expansion of NK cells expressing germ-line encoded receptors, activation of other innate immune cells to an activated state that confers a short-term "immune memory". In this sense, "adaptive immunity" more resembles the concept of "activated state" or "heterostasis", thus returning in sense to the physiological sense of "adaptation" to environmental changes. Unlike the innate immune system, the acquired immune system is specific to a particular pathogen. Acquired immunity can provide long-lasting protection. In other cases it does not provide lifetime protection; the acquired system response destroys invading pathogens and any toxic molecules they produce. Sometimes the acquired system is unable to distinguish harmful from harmless foreign molecules. Antigens are any substances; the cells that carry out the acquired immune response are white blood cells known as lymphocytes. Two main broad classes—antibody responses and cell mediated immune response—are carried by two different lymphocytes.
In antibody responses, B cells are activated to secrete antibodies, which are proteins known as immunoglobulins. Antibodies travel through the bloodstream and bind to the foreign antigen causing it to inactivate, which does not allow the antigen to bind to the host. In acquired immunity, pathogen-specific receptors are "acquired" during the lifetime of the organism; the acquired response is called "adaptive" because it prepares the body's immune system for future challenges. The system is adaptable because of somatic hypermutation, VJ recombination; this mechanism allows a small number of genes to generate a vast number of different antigen receptors, which are uniquely expressed on each individual lymphocyte. Since the gene rearrangement leads to an irreversible change in the DNA of each cell, all progeny of that cell inherit genes that encode the same receptor specificity, including the memory B cells and memory T cells that are the keys to long-lived specific immunity. A theoretical framework explaining the workings of the acquired immune system is provided by immune network theory.
This theory, which builds on established concepts of clonal selection, is being applied in the search for an HIV vaccine. Acquired immunity is triggered in vertebrates when a pathogen evades the innate immune system and generates a threshold level of antigen and generates "stranger" or "danger" signals activating dendritic cells; the major functions of the acquired immune system include: Recognition of specific "non-self" antigens in the presence of "self", during the process of antigen presentation. Generation of responses that are tailored to maximally eliminate specific pathoge
International Standard Serial Number
An International Standard Serial Number is an eight-digit serial number used to uniquely identify a serial publication, such as a magazine. The ISSN is helpful in distinguishing between serials with the same title. ISSN are used in ordering, interlibrary loans, other practices in connection with serial literature; the ISSN system was first drafted as an International Organization for Standardization international standard in 1971 and published as ISO 3297 in 1975. ISO subcommittee TC 46/SC 9 is responsible for maintaining the standard; when a serial with the same content is published in more than one media type, a different ISSN is assigned to each media type. For example, many serials are published both in electronic media; the ISSN system refers to these types as electronic ISSN, respectively. Conversely, as defined in ISO 3297:2007, every serial in the ISSN system is assigned a linking ISSN the same as the ISSN assigned to the serial in its first published medium, which links together all ISSNs assigned to the serial in every medium.
The format of the ISSN is an eight digit code, divided by a hyphen into two four-digit numbers. As an integer number, it can be represented by the first seven digits; the last code digit, which may be 0-9 or an X, is a check digit. Formally, the general form of the ISSN code can be expressed as follows: NNNN-NNNC where N is in the set, a digit character, C is in; the ISSN of the journal Hearing Research, for example, is 0378-5955, where the final 5 is the check digit, C=5. To calculate the check digit, the following algorithm may be used: Calculate the sum of the first seven digits of the ISSN multiplied by its position in the number, counting from the right—that is, 8, 7, 6, 5, 4, 3, 2, respectively: 0 ⋅ 8 + 3 ⋅ 7 + 7 ⋅ 6 + 8 ⋅ 5 + 5 ⋅ 4 + 9 ⋅ 3 + 5 ⋅ 2 = 0 + 21 + 42 + 40 + 20 + 27 + 10 = 160 The modulus 11 of this sum is calculated. For calculations, an upper case X in the check digit position indicates a check digit of 10. To confirm the check digit, calculate the sum of all eight digits of the ISSN multiplied by its position in the number, counting from the right.
The modulus 11 of the sum must be 0. There is an online ISSN checker. ISSN codes are assigned by a network of ISSN National Centres located at national libraries and coordinated by the ISSN International Centre based in Paris; the International Centre is an intergovernmental organization created in 1974 through an agreement between UNESCO and the French government. The International Centre maintains a database of all ISSNs assigned worldwide, the ISDS Register otherwise known as the ISSN Register. At the end of 2016, the ISSN Register contained records for 1,943,572 items. ISSN and ISBN codes are similar in concept. An ISBN might be assigned for particular issues of a serial, in addition to the ISSN code for the serial as a whole. An ISSN, unlike the ISBN code, is an anonymous identifier associated with a serial title, containing no information as to the publisher or its location. For this reason a new ISSN is assigned to a serial each time it undergoes a major title change. Since the ISSN applies to an entire serial a new identifier, the Serial Item and Contribution Identifier, was built on top of it to allow references to specific volumes, articles, or other identifiable components.
Separate ISSNs are needed for serials in different media. Thus, the print and electronic media versions of a serial need separate ISSNs. A CD-ROM version and a web version of a serial require different ISSNs since two different media are involved. However, the same ISSN can be used for different file formats of the same online serial; this "media-oriented identification" of serials made sense in the 1970s. In the 1990s and onward, with personal computers, better screens, the Web, it makes sense to consider only content, independent of media; this "content-oriented identification" of serials was a repressed demand during a decade, but no ISSN update or initiative occurred. A natural extension for ISSN, the unique-identification of the articles in the serials, was the main demand application. An alternative serials' contents model arrived with the indecs Content Model and its application, the digital object identifier, as ISSN-independent initiative, consolidated in the 2000s. Only in 2007, ISSN-L was defined in the
A lymph node or lymph gland is an ovoid or kidney-shaped organ of the lymphatic system, of the adaptive immune system, present throughout the body. They are linked by the lymphatic vessels as a part of the circulatory system. Lymph nodes are major sites of B and T lymphocytes, other white blood cells. Lymph nodes are important for the proper functioning of the immune system, acting as filters for foreign particles and cancer cells. Lymph nodes do not have a detoxification function, dealt with by the liver and kidneys. In the lymphatic system the lymph node is a secondary lymphoid organ. A lymph node is enclosed in a fibrous capsule and is made up of an outer cortex and an inner medulla. Lymph nodes have clinical significance, they become inflamed or enlarged in various diseases which may range from trivial throat infections, to life-threatening cancers. The condition of the lymph nodes is important in cancer staging, which decides the treatment to be used, determines the prognosis; when swollen, inflamed or enlarged, lymph nodes can be hard, tender.
Lymph nodes are oval shaped and range in size from a few millimeters to about 1 -- 2 cm long. Each lymph node is surrounded by a fibrous capsule, which extends inside the lymph node to form trabeculae; the substance of the lymph node is divided into the inner medulla. The cortex is continuous around the medulla except where the medulla comes into direct contact with the hilum. Thin reticular fibers of reticular connective tissue, elastin form a supporting meshwork called a reticulin inside the node. B cells are found in the outer cortex where they are clustered together as follicular B cells in lymphoid follicles and the T cells are in the paracortex; the lymph node is divided into compartments called lymph nodules each consisting of a cortical region of combined follicle B cells, a paracortical region of T cells, a basal part of the nodule in the medulla. The number and composition of follicles can change when challenged by an antigen, when they develop a germinal center. Elsewhere in the node, there are only occasional leukocytes.
As part of the reticular network there are follicular dendritic cells in the B cell follicle and fibroblastic reticular cells in the T cell cortex. The reticular network not only provides the structural support, but the surface for adhesion of the dendritic cells and lymphocytes, it allows exchange of material with blood through the high endothelial venules and provides the growth and regulatory factors necessary for activation and maturation of immune cells. Lymph enters the convex side of the lymph node through multiple afferent lymphatic vessels, flows through spaces called sinuses. A lymph sinus which includes the subcapsular sinus, is a channel within the node, lined by endothelial cells along with fibroblastic reticular cells and this allows for the smooth flow of lymph through them; the endothelium of the subcapsular sinus is continuous with that of the afferent lymph vessel and with that of the similar sinuses flanking the trabeculae and within the cortex. All of these sinuses drain the filtered lymphatic fluid into the medullary sinuses, from where the lymph flows into the efferent lymph vessels to exit the node at the hilum on the concave side.
These vessels are smaller and don't allow the passage of the macrophages so that they remain contained to function within the lymph node. In the course of the lymph, lymphocytes may be activated as part of the adaptive immune response; the lymph node capsule is composed of dense irregular connective tissue with some plain collagenous fibers, from its internal surface are given off a number of membranous processes or trabeculae. They pass inward, radiating toward the center of the node, for about one-third or one-fourth of the space between the circumference and the center of the node. In some animals they are sufficiently well-marked to divide the peripheral or cortical portion of the node into a number of compartments, but in humans this arrangement is not obvious; the larger trabeculae springing from the capsule break up into finer bands, these interlace to form a mesh-work in the central or medullary portion of the node. In these trabecular spaces formed by the interlacing trabeculae is contained the proper lymph node substance or lymphoid tissue.
The node pulp does not, however fill the spaces, but leaves, between its outer margin and the enclosing trabeculae, a channel or space of uniform width throughout. This is termed the subcapsular sinus. Running across it are a number of finer trabeculae of reticular connective tissue, the fibers of which are, for the most part, covered by ramifying cells; the subcapsular sinus is the space between the capsule and the cortex which allows the free movement of lymphatic fluid and so contains few lymphocytes. It is continuous with the similar lymph sinuses; the lymph node contains lymphoid tissue, i.e. a meshwork or fibers called reticulum with white blood cells enmeshed in it. The regions where there are few cells within the meshwork are known as lymph sinus, it is lined by reticular cells and fixed macrophages. The subcapsular sinus has clinical importance as it is the most location where the earliest manifestations of a metastatic carcinoma in a lymph node would be found; the cortex of the lymph node is the outer portion of the node, underneath the capsule and the subcapsular sinus.
It has a deeper part known as the paracortex. The subcapsular sinus drains to the trabecul sinuses, the lymph flows into the medullary sinuses; the outer cortex consists of the B c
Anatomical terminology is a form of scientific terminology used by anatomists and health professionals such as doctors. Anatomical terminology uses many unique terms and prefixes deriving from Ancient Greek and Latin; these terms can be confusing to those unfamiliar with them, but can be more precise, reducing ambiguity and errors. Since these anatomical terms are not used in everyday conversation, their meanings are less to change, less to be misinterpreted. To illustrate how inexact day-to-day language can be: a scar "above the wrist" could be located on the forearm two or three inches away from the hand or at the base of the hand. By using precise anatomical terminology such ambiguity is eliminated. An international standard for anatomical terminology, Terminologia Anatomica has been created. Anatomical terminology has quite regular morphology, the same prefixes and suffixes are used to add meanings to different roots; the root of a term refers to an organ or tissue. For example, the Latin names of structures such as musculus biceps brachii can be split up and refer to, musculus for muscle, biceps for "two-headed", brachii as in the brachial region of the arm.
The first word describes what is being spoken about, the second describes it, the third points to location. When describing the position of anatomical structures, structures may be described according to the anatomical landmark they are near; these landmarks may include structures, such as the umbilicus or sternum, or anatomical lines, such as the midclavicular line from the centre of the clavicle. The cephalon or cephalic region refers to the head; this area is further differentiated into the cranium, frons, auris, nasus and mentum. The neck area is called cervical region. Examples of structures named according to this include the frontalis muscle, submental lymph nodes, buccal membrane and orbicularis oculi muscle. Sometimes, unique terminology is used to reduce confusion in different parts of the body. For example, different terms are used when it comes to the skull in compliance with its embryonic origin and its tilted position compared to in other animals. Here, Rostral refers to proximity to the front of the nose, is used when describing the skull.
Different terminology is used in the arms, in part to reduce ambiguity as to what the "front", "back", "inner" and "outer" surfaces are. For this reason, the terms below are used: Radial referring to the radius bone, seen laterally in the standard anatomical position. Ulnar referring to the ulna bone, medially positioned when in the standard anatomical position. Other terms are used to describe the movement and actions of the hands and feet, other structures such as the eye. International morphological terminology is used by the colleges of medicine and dentistry and other areas of the health sciences, it facilitates communication and exchanges between scientists from different countries of the world and it is used daily in the fields of research and medical care. The international morphological terminology refers to morphological sciences as a biological sciences' branch. In this field, the form and structure are examined as well as the changes or developments in the organism, it is functional.
It covers the gross anatomy and the microscopic of living beings. It involves the anatomy of the adult, it includes comparative anatomy between different species. The vocabulary is extensive and complex, requires a systematic presentation. Within the international field, a group of experts reviews and discusses the morphological terms of the structures of the human body, forming today's Terminology Committee from the International Federation of Associations of Anatomists, it deals with the anatomical and embryologic terminology. In the Latin American field, there are meetings called Iberian Latin American Symposium Terminology, where a group of experts of the Pan American Association of Anatomy that speak Spanish and Portuguese and studies the international morphological terminology; the current international standard for human anatomical terminology is based on the Terminologia Anatomica. It was developed by the Federative Committee on Anatomical Terminology and the International Federation of Associations of Anatomists and was released in 1998.
It supersedes Nomina Anatomica. Terminologia Anatomica contains terminology for about 7500 human gross anatomical structures. For microanatomy, known as histology, a similar standard exists in Terminologia Histologica, for embryology, the study of development, a standard exists in Terminologia Embryologica; these standards specify accepted names that can be used to refer to histological and embryological structures in journal articles and other areas. As of September 2016, two sections of the Terminologia Anatomica, including central nervous system and peripheral nervous system, were merged to form the Terminologia Neuroanatomica; the Terminologia Anatomica has been perceived with a considerable criticism regarding its content including coverage and spelling mistakes and errors. Anatomical terminology is chosen to highlight the relative location of body structures. For instance, an anatomist might describe one band of tissue as "inferior to" another or a physician might describe a tumor as "superficial to" a deeper body structure.
Anatomical terms used to describe location
The large intestine known as the large bowel, is the last part of the gastrointestinal tract and of the digestive system in vertebrates. Water is absorbed here and the remaining waste material is stored as feces before being removed by defecation; the colon is the largest portion of the large intestine, so many mentions of the large intestine and colon overlap in meaning whenever anatomic precision is not the focus. Most sources define the large intestine as the combination of the cecum, colon and anal canal; some other sources exclude the anal canal. In humans, the large intestine begins in the right iliac region of the pelvis, just at or below the waist, where it is joined to the end of the small intestine at the cecum, via the ileocecal valve, it continues as the colon ascending the abdomen, across the width of the abdominal cavity as the transverse colon, descending to the rectum and its endpoint at the anal canal. Overall, in humans, the large intestine is about 1.5 metres long, about one-fifth of the whole length of the gastrointestinal tract.
The colon is the last part of the digestive system. It extracts water and salt from solid wastes before they are eliminated from the body and is the site in which flora-aided fermentation of unabsorbed material occurs. Unlike the small intestine, the colon does not play a major role in absorption of foods and nutrients. About 1.5 litres or 45 ounces of water arrives in the colon each day. The length of the adult human male colon is 65 inches or 166 cm, on average, for females it is 155 cm. In mammals, the colon consists of five sections: the cecum plus the ascending colon, the transverse colon, the descending colon, the sigmoid colon, the rectum. Sections of the colon are: The ascending colon including the cecum and appendix The transverse colon including the colic flexures and transverse mesocolon The descending colon The sigmoid colon – the s-shaped region of the large intestine The rectumThe parts of the colon are either intraperitoneal or behind it in the retroperitoneum. Retroperitoneal organs in general do not have a complete covering of peritoneum, so they are fixed in location.
Intraperitoneal organs are surrounded by peritoneum and are therefore mobile. Of the colon, the ascending colon, descending colon and rectum are retroperitoneal, while the cecum, transverse colon and sigmoid colon are intraperitoneal; this is important as it affects which organs can be accessed during surgery, such as a laparotomy. The average inner diameter of sections of the colon in centimeters are cecum 8.7, ascending colon 6.6, transverse colon 5.8, descending/sigmoid colon 6.3 and rectum near rectal/sigmoid junction 5.7. The cecum is the first section of the colon and involved in the digestion, while the appendix which develops embryologically from it, is a structure of the colon, not involved in digestion and considered to be part of the gut-associated lymphoid tissue; the function of the appendix is uncertain, but some sources believe that the appendix has a role in housing a sample of the colon's microflora, is able to help to repopulate the colon with bacteria if the microflora has been damaged during the course of an immune reaction.
The appendix has been shown to have a high concentration of lymphatic cells. The ascending colon is the first of four sections of the large intestine, it is connected to the small intestine by a section of bowel called the cecum. The ascending colon runs upwards through the abdominal cavity toward the transverse colon for eight inches. One of the main functions of the colon is to remove the water and other key nutrients from waste material and recycle it; as the waste material exits the small intestine through the ileocecal valve, it will move into the cecum and to the ascending colon where this process of extraction starts. The unwanted waste material is moved upwards toward the transverse colon by the action of peristalsis; the ascending colon is sometimes attached to the appendix via Gerlach's valve. In ruminants, the ascending colon is known as the spiral colon. Taking into account all ages and sexes, colon cancer occurs here most often; the transverse colon is the part of the colon from the hepatic flexure known as the right colic, to the splenic flexure known as the left colic.
The transverse colon hangs off the stomach, attached to it by a large fold of peritoneum called the greater omentum. On the posterior side, the transverse colon is connected to the posterior abdominal wall by a mesentery known as the transverse mesocolon; the transverse colon is encased in peritoneum, is therefore mobile. The proximal two-thirds of the transverse colon is perfused by the middle colic artery, a branch of the superior mesenteric artery, while the latter third is supplied by branches of the inferior mesenteric artery; the "watershed" area between these two blood supplies, which represents the embryologic division between the midgut and hindgut, is an area sensitive to ischemia. The descending colon is the part of the colon from the splenic flexure to the beginning of the sigmoid colon. One function of the descending colon in the digestive system is to store feces that will be emptied into the rectum, it is retroperitoneal in two-thirds of humans. In the other third, it has a mesentery.
The arterial supply comes via the left colic artery. The descending colon is called the distal gut, as it is further along the gastrointestinal tract than the proximal gut. Gut flora are dense
An organ system is a group of organs that work together as a biological system to perform one or more functions. Each organ system does a particular job in the body, is made up of certain tissues; these specific systems are studied in anatomy. They are present in many types of animals. Respiratory system: the organs used for breathing, the pharynx, bronchi and diaphragm. Digestive system: digestion and processing food with salivary glands, stomach, gallbladder, intestines and anus. Cardiovascular system: and channeling blood to and from the body and lungs with heart and blood vessels. Urinary system: kidneys, ureters and urethra involved in fluid balance, electrolyte balance and excretion of urine. Integumentary system: skin, hair and nails. Skeletally system: structural support and protection with bones, cartilage and tendons. Endocrine system: communication within the body using hormones made by endocrine glands such as the hypothalamus, pituitary gland, pineal gland, thyroid and adrenal glands.
Lymphatic system: the transfer of lymph between tissues and the blood stream. Includes the functions of immune responses and the development of antibodies. Our bodies consist of a number of biological systems that carry out specific functions necessary for everyday living; the job of the circulatory system is to move blood, oxygen, carbon dioxide, hormones, around the body. It consists of the heart, blood vessels and veins. Immune system: protects the organism from foreign bodies. Nervous system: collecting and processing information with brain, spinal cord, peripheral nervous system and sense organs. Sensory systems: visual system, auditory system, olfactory system, gustatory system, somatosensory system, vestibular system. Muscular system: allows for manipulation of the environment, provides locomotion, maintains posture, produces heat. Includes skeletal muscles, smooth muscles and cardiac muscle. Reproductive system: the sex organs, such as ovaries, fallopian tubes, vagina, mammary glands, testes, vas deferens, seminal vesicles and prostate