Physiology is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs and biomolecules carry out the chemical and physical functions in a living system. According to the classes of organisms, the field can be divided into medical physiology, animal physiology, plant physiology, cell physiology, comparative physiology. Central to physiological functioning are biophysical and biochemical processes, homeostatic control mechanisms, communication between cells. Physiological state is the condition of normal function, while pathological state refers to abnormal conditions, including human diseases; the Nobel Prize in Physiology or Medicine is awarded by the Royal Swedish Academy of Sciences for exceptional scientific achievements in physiology related to the field of medicine. Human physiology seeks to understand the mechanisms that work to keep the human body alive and functioning, through scientific enquiry into the nature of mechanical and biochemical functions of humans, their organs, the cells of which they are composed.
The principal level of focus of physiology is at the level of systems within systems. The endocrine and nervous systems play major roles in the reception and transmission of signals that integrate function in animals. Homeostasis is a major aspect with regard to such interactions within plants as well as animals; the biological basis of the study of physiology, integration refers to the overlap of many functions of the systems of the human body, as well as its accompanied form. It is achieved through communication that occurs in a variety of both electrical and chemical. Changes in physiology can impact the mental functions of individuals. Examples of this would be toxic levels of substances. Change in behavior as a result of these substances is used to assess the health of individuals. Much of the foundation of knowledge in human physiology was provided by animal experimentation. Due to the frequent connection between form and function and anatomy are intrinsically linked and are studied in tandem as part of a medical curriculum.
Plant physiology is a subdiscipline of botany concerned with the functioning of plants. Related fields include plant morphology, plant ecology, cell biology, genetics and molecular biology. Fundamental processes of plant physiology include photosynthesis, plant nutrition, nastic movements, photomorphogenesis, circadian rhythms, seed germination and stomata function and transpiration. Absorption of water by roots, production of food in the leaves, growth of shoots towards light are examples of plant physiology. Although there are differences between animal and microbial cells, the basic physiological functions of cells can be divided into the processes of cell division, cell signaling, cell growth, cell metabolism. Involving evolutionary physiology and environmental physiology, comparative physiology considers the diversity of functional characteristics across organisms; the study of human physiology as a medical field originates in classical Greece, at the time of Hippocrates. Outside of Western tradition, early forms of physiology or anatomy can be reconstructed as having been present at around the same time in China and elsewhere.
Hippocrates incorporated his belief system called the theory of humours, which consisted of four basic substance: earth, water and fire. Each substance is known for having a corresponding humour: black bile, phlegm and yellow bile, respectively. Hippocrates noted some emotional connections to the four humours, which Claudius Galenus would expand on; the critical thinking of Aristotle and his emphasis on the relationship between structure and function marked the beginning of physiology in Ancient Greece. Like Hippocrates, Aristotle took to the humoral theory of disease, which consisted of four primary qualities in life: hot, cold and dry. Claudius Galenus, known as Galen of Pergamum, was the first to use experiments to probe the functions of the body. Unlike Hippocrates, Galen argued that humoral imbalances can be located in specific organs, including the entire body, his modification of this theory better equipped doctors to make more precise diagnoses. Galen played off of Hippocrates idea that emotions were tied to the humours, added the notion of temperaments: sanguine corresponds with blood.
Galen saw the human body consisting of three connected systems: the brain and nerves, which are responsible for thoughts and sensations. Galen was the founder of experimental physiology, and for the next 1,400 years, Galenic physiology was a influential tool in medicine. Jean Fernel, a French physician, introduced the term "physiology". Galen, Ibn al-Nafis, Michael Servetus, Realdo Colombo, Amato Lusitano and William Harvey, are credited as making important discoveries in the circulation of the blood. Santorio Santorio in 1610s was the first to use a device to measure the pulse rate, a thermoscope to measure temperature. In 1791 Luigi Galvani described the role of electricity in nerves of dissected frogs. In 1811, César Julien Jean Legallois studied respiration in animal dissection and lesions and found the center of respiration in the
A backstage pass is a credential which allows its bearer access to restricted areas at a performance or conference venue, most associated with rock music groups. Backstage passes can come in the form of stickers or wristbands. To deter counterfeiting, these passes include holograms and unique artwork. After the performance, backstage passes sometimes become memorabilia sold to fans when the pass is signed by a performer or famous person. There are a number of different types of backstage passes: Access All Areas allows the bearer access to the venue both before and after the performance; such passes are restricted to the performers and artist management. Important Person / Guest allows the bearer limited access both before and after the performance to specific rooms within the venue, such as the green room; such passes are allocated to close friends of the performer and promoter. After Show allows the bearer limited access after the performance to specific rooms within the performance venue, such as the green room.
Such passes are allocated to friends of the performer and promoter. Working allows the bearer access to the majority of the venue, apart from the dressing rooms for the performer; such passes are allocated to production and sound technicians. Local Crew passes are used by those; these passes may only be valid after the performance, not during. Photo passes permit photographs with a professional camera; these cameras have a detachable lens, or lens bigger than 35mm and subsequently are banned to the public. This pass may entitle the bearer access to the front of the stage for a short amount of the performance. Other employee passes for people who work specific jobs in support of the act, such as catering, security and merchandising personnel. Ticket
Year's Best Science Fiction Novels: 1953 is a 1953 anthology of science fiction novels and novellas edited by E. F. Bleiler and T. E. Dikty. An abridged edition was published in the UK by The Bodley Head in 1955 under the title Category Phoenix; the stories had appeared in 1952 in the magazines Astounding, Galaxy Science Fiction and Thrilling Wonder Stories. Introduction, by Everett F. Bleiler & T. E. Dikty "Firewater", by William Tenn "Category Phoenix", by Boyd Ellanby "Surface Tension", by James Blish "The Gadget Had a Ghost", by Murray Leinster "Conditionally Human", by Walter M. Miller, Jr. P. Schuyler Miller noted that the editors selected stories "for variety as much as'importance,' literary elegance, or any other such self-conscious quality." Contento, William G. "Index to Science Fiction Anthologies and Collections". Retrieved 2008-01-24