Biology questions and answers F

Biology F

What is F-430 ?

A tetrapyrrole structure containing nickel, a component of the ENZYME methyl-coenzyme M reductase, which is involved in the formation of methane in methanogenic bacteria. The highly reduced macrocyclic structure, related to PORPHYRINs and CORRINs, is termed a CORPHIN.

What is facilitated diffusion ?

A process by which carrier proteins, also called permeases or transporters or ion channels, in the cell membrane transport substances such as glucose, sodium, and chloride ions into or out of cells down a concentration (electrochemical) gradient; does not require the use of metabolic energy.

What is facultative anaerobe ?

A facultative anaerobe is a microorganism that makes ATP by aerobic respiration if oxygen is present but, if absent, switches to fermentation under anaerobic conditions.

What is facultative organism ?

Any organism that changes a metabolic pathway to another when needed.

What is facultative saprophyte ?

Any organism that is usually parasitic but can also live as a SAPROPHYTE.

What is facultative symbiont ?

Any organism that chooses a symbiotic relationship with a host only if the relationship presents itself but is not physiologically required to do so for survival.

Who was Fahrenheit, Daniel Gabriel

Fahrenheit, Daniel Gabriel (1686–1736) was German Instrument Maker, Physicist Daniel Gabriel Fahrenheit, a German instrument maker and physicist, was born in Danzig, Germany (now Gdansk, Poland), in 1686, the oldest of five children. Fahrenheit’s major contributions lay in the creation of the first accurate thermometers in 1709 and a temperature scale in 1724 that bears his name today.

When he was 15 years of age, his parents died of mushroom poisoning. The city council placed the four younger Fahrenheit orphans in foster homes and apprenticed Daniel to a merchant who taught him bookkeeping. He was sent to Amsterdam around 1714, where he learned of the Florentine thermometer, invented in Italy 60 years prior in 1654 by the grand duke of Tuscany, Ferdinand II (1610–70), a member of the powerful Medici family. For some unknown reason, it sparked his curiosity and he decided to make thermometers for a living. He abandoned his bookkeeping apprenticeship, whereby Dutch authorities issued warrants for his arrest. While on the run, he spent several years traveling around Europe and meeting scientists, such as Danish astronomer Olaus Roemer. Eventually he returned to Amsterdam in 1717 and remained in the Netherlands for the rest of his life.

What seems so simple today—having a fixed scale and fixed points on a thermometer—was not obvious in Fahrenheit’s time, when several makers used different types of scales and liquids for measuring. In 1694 Carlo Renaldini, a member of the Academia del Cimento and professor of philosophy at the University of Pisa, was the first to suggest taking the boiling and freezing points of water as the fixed points. The academy was founded by Prince Leopoldo de Medici and the Grand Duke Ferdinand II in 1657 with the purpose of examining the natural philosophy of Aristotle. The academy was active sporadically over 10 years and concluded its work in 1667 with the publication of the Saggi di Naturali Esperienze.

Unfortunately, Florentine thermometers, or any thermometers of the time, were not very accurate; no two thermometers gave the same temperature, since there was no universal acceptance of liquid type or agreement on what to use for a scale. Makers of Florentine thermometers marked the low end of the scale as the coldest day in Florence that year and the high end of the scale as the hottest day. Because temperature fluctuations naturally occur over the years, no two thermometers gave the same temperature. For several years Fahrenheit experimented with this problem, finally devising an accurate alcohol thermometer in 1709 and the first mercury or “quicksilver” thermometer in 1714.

Fahrenheit’s first thermometers, from about 1709 to 1715, contained a column of alcohol that directly expanded and contracted, based on a design made by Danish astronomer Olaus Romer in 1708, which Fahrenheit personally reviewed. Romer used alcohol (actually wine) as the liquid, but his thermometer had two fixed reference points. He selected 60 degrees for the temperature of boiling water and 7.5 degrees for melting ice.

Fahrenheit eventually devised a temperature scale for his alcohol thermometers with three points calibrated at 32 degrees for freezing water, 96 degrees for body temperature (based on the thermometer being in a healthy man’s mouth or under the armpit), and zero degrees fixed at the freezing point of ice and salt, believed at the time to be the coldest possible temperature. The scale was etched in 12 major points (with zero, four, and 12 as three points) and eight gradations between the major points, giving him a total of 96 points for his scale for body temperature on his thermometer.

Because his thermometers showed such consistency in their measurements, mathematician Christian Wolf at Halle, Prussia, devoted a whole paper in an edition of Acta Eruditorum, one of the most important international journals of the time, on two of Fahrenheit’s thermometers that were given to him in 1714. From 1682 until it ceased publication in 1731, the Latin Acta Eruditorum, published monthly in Leipzig and supported by the duke of Saxony, was one of the most important international journals. The periodical was founded by Otto Mencke, professor of morals and practical philosophy, and mathematician Gottfried Wilhelm Leibnitz. Written in Latin, the journal covered science and social science and was primarily a vehicle for reviewing books. In 1724 Fahrenheit published a paper, “Experimenta circa gradum caloris liquorum nonnullorum ebullientium instituta (Experiments done on the degree of heat of a few boiling liquids), in the Royal Society’s publication Philosophical Transactions and was admitted to the Royal Society the same year.

Fahrenheit decided to substitute mercury for the alcohol because its rate of expansion was more constant than that of alcohol and could be used over a wider range of temperatures. Fahrenheit, like ISAAC NEWTON before him, realized that it was more accurate to base the thermometer on a substance that changed consistently based on temperature instead of simply on the hottest or coldest day of the year, like the Florentine models. Mercury also had a much wider temperature range than alcohol. The choice of mercury as a benchmark was contrary to the common thought at the time, promoted by Halley as late as 1693, who believed that mercury could not be used for thermometers because of its low coefficient of expansion.

Fahrenheit later adjusted his temperature scale to ignore body temperature as a fixed point, bringing the scale to just the freezing and boiling of water. After his death, scientists recalibrated his thermometer so that the boiling point of water was the highest point, changing it to 212 degrees, as Fahrenheit had earlier indicated in a publication on the boiling points of various liquids. The freezing point became 32 degrees, and body temperature became 98.6 degrees. This is the scale that is presently used in thermometers in the United States and some English-speaking countries, although most scientists use the Celsius scale.

By 1779 there were some 19 different scales being used for thermometers, but it was Fahrenheit, along with astronomer ANDERS CELSIUS and Jean Christin— whose scales were presented in 1742 and 1743—who helped finally set the standards for an accurate thermometer that are still used today. Besides making thermometers, Fahrenheit also was the first to show that the boiling point of liquids varies at different atmospheric pressures, and he suggested this as a principle for the construction of barometers. Among his other contributions were a pumping device for draining the Dutch polders and a hygrometer for measuring atmospheric humidity.

Fahrenheit died on September 16, 1736, in The Hague at the age of 50 years. There is virtually no one in the English-speaking countries today who does not have a thermometer with his initial (F) on it.

What is family ?

The taxonomic category between order and tribe, but if no tribe exists, then it is the category between order and genus. Also a social unit related by marriage, descent, or kinship.

What is farsightedness ?

A condition in eyesight where distant objects can be seen better than objects that are closer. It is the inability of images to focus properly on the retina of the eye. The eye is too short or the cornea is too flat, so that the images focus beyond the retina and cause close objects to appear blurry. Also called hyperopia or presbyopia, when the lens of the eye begins to lose elasticity (normal aging process).

What is fat (general) ?

Any substance made up of lipids or fatty acids that supply calories to the body and can be found in solid or liquid form (e.g., margarine, vegetable oil); three fatty acids linked to a glycerol molecule form fat.

What is fat (triacylglycerol) ?

Triacylglycerols are storage lipids, comprising three fatty acids attached to a glycerol molecule, found mostly stored in adipose (fat) cells and tissues. They are highly concentrated regions of metabolic energy. Because there are abundant reduced CH groups available in fats for oxidation-required energy production, they are excellent storage containers of energy. Fats can be found in plants, animals, and animal plasma lipoproteins for lipid transport. Formerly known as triglyceride.

What is fatty acid ?

Fatty acids are the components of two lipid types mostly found in cells in the form of large lipids or small amounts in free form: storage fats and structural phospholipids. They consist of long hydrocarbon chains of varying length (from four to 24 carbon atoms), containing a terminal carbonyl group at one end and may be saturated (has only a single carbon-to-carbon bond) or unsaturated (one or more double or triple carbon-to-carbon bonds). The number and location of double bonds also vary for the different fatty acids. More than 70 different kinds have been found in cells. Saturated fatty acids have higher levels of blood cholesterol, since they have a regulating effect on its synthesis, but unsaturated ones do not have that effect and thus they are more often promoted nutritionally. Some fatty acids are palmitic acid, palmitoleic acid, alpha-linolenic acid, eleostearic acid, linoleic acid, oleic acid, and elaidic acid. Three fatty acids linked to a glycerol molecule form fat.

What is fauna ?

All wild birds and all wild animals (both aquatic and terrestrial); includes wild mammals, reptiles, fauna 125 amphibians, and aquatic and nonaquatic invertebrate animals, and all such wild animals’ eggs, larvae, pupae, or other immature stage and young.

What is feedback inhibition (end-product inhibition) ?

A way for the end product of a cell’s biosynthetic pathway to stop the activity of the first enzymes in that pathway, thereby controlling the enzymatic activity; it stops the synthesis of the product.

What is female ?

Sex classification by gender. The individual in a sexually reproducing species that produces eggs. Female mammals, for example, nourish their young with milk. In humans, females have two X chromosomes.

What is FeMo-cofactor ?

An inorganic CLUSTER that is found in the FeMo protein of the molybdenum-NITROGENASE and is essential for the catalytic reduction of N2 to ammonia. This cluster contains Fe, Mo, and S in a 7:1:9 ratio. The structure of the COFACTOR within the FeMo protein can be described in terms of two cuboidal SUBUNITs, Fe4S3 and MoFe3S3 bridged by three S2– ions and “anchored” to the protein by a histidine bound via an imidazole group to the Mo atom and by a cysteine bound via a deprotonated SH group to an Fe atom of the Fe4S3 subunit. The Mo atom at the periphery of the molecule is six-coordinate and, in addition to the three sulfido LIGANDs and the histidine imidazole, is also bound to two oxygen atoms from an (R)-homocitrate molecule.

What is Fenton reaction ?

Fe2+ + H2O2 Fe3+ + OH. + OH–. This is the iron-salt-dependent decomposition of dihydrogen peroxide, generating the highly reactive hydroxyl radical, possibly via an oxoiron(IV) intermediate. Addition of a reducing agent such as ascorbate leads to formation of an acyclic compound, which increases the damage to biological molecules.

What is fermentation ?

The anaerobic decomposition of complex organic substances by microorganisms such as bacteria, molds, or yeast, called ferments, on a fermentation substrate that produce simpler substances or some other desired effect, such as the yielding of ethanol and carbon dioxide from yeast for commercial purposes, the production of ATP and energy production, and the development of antibiotics and enzymes. Fermentation is used by microflora of the large intestine to break down indigestible carbohydrates.

Large fermentors are used to culture microorganisms for the production of some commercially valuable products such as bread, beer, wine, and other beverages.

What is ferredoxin ?

A protein containing more than one iron and ACID-LABILE SULFIDE that displays electron-transfer activity but not classical ENZYME function.

What is ferriheme ?

An iron(III) PORPHYRIN COORDINATION complex.

What is ferritin ?

An iron storage protein consisting of a shell of 24 protein SUBUNITs encapsulating up to 4,500 iron atoms in the form of a hydrated iron(III) oxide.

What is ferrochelatase ?

An ENZYME that catalyzes the insertion of iron into PROTOPORPHYRIN IX to form HEME. The mammalian enzyme contains an IRON-SULFUR CLUSTER.

What is ferroheme ?

An iron(II) PORPHYRIN COORDINATION complex.

What is ferromagnetic ?

If there is coupling between the individual magnetic dipole moments of a PARAMAGNETIC sample, spontaneous ordering of the moments will occur at low temperatures. If this ordering results in an electronic ground state in which the moments are aligned in the same direction (parallel), the substance is said to be “ferromagnetic.” If the ordering results in an electronic ground state in which the moments are aligned in opposite directions, the substance is said to be “antiferromagnetic.”

What is fertilization ?

The combining of two gametes from different sexes to form a zygote, e.g., the penetration of sperm into the egg and the resulting combining of genetic material from both that develops into an embryo. The process involves karyogamy, the fusion of nuclei of both gametes, and plasmogamy, the fusion of cytoplasm. Each gamete contains a haploid set of chromosomes, with the resulting nucleus containing a diploid set of chromosomes. Fertilization can also be self-induced by the fusion of male and female gametes from the same euploid (nucleus of a cell contains exact multiples of the haploid number of chromosomes) organism; cross fertilized by the fusion of male and female gametes from different euploid individuals; or double fertilized, in which two separate sperm cells unite with two cells in the embryo sac to form the zygote and endosperm, such as in angiosperms.

In agriculture, fertilization means the application of nutrients, a fertilizer, to soil in order to promote growth and development of domestic or crop plants.

What is fetus ?

An unborn offspring in the postembryonic stage where the major features of the organism can be seen.

What is F factor ?

A bacterial plasmid, which is a piece of DNA that is able to replicate independently of the chromosome, that allows a prokaryote (cell with no nucleus) to join together with and pass DNA. An episome that can replicate by itself or in integrated form and move from one bacterium to another while conjugating. A circular piece of DNA that can replicate independently of the bacterial chromosome or integrate and replicate as part of the chromosome.

What is fiber ?

A long-walled plant cell that is often dead at maturity, is lignified, and reinforces the xylem of angiosperms, giving elasticity, flexibility, tensile strength, and mechanical support to plant structure. Also part of sclerenchyma tissue, which is thickened cell walls of lignin, composed of both sclereids, short cells, and the longer fibers, and lacking a living protoplast when mature.

In human nutrition, fiber is a carbohydrate that resists the action of digestive enzymes and passes through the human digestive system virtually unchanged, without being broken down into nutrients. There are insoluble fibers, found in wholegrain products and vegetables, that help the digestive system by moving stools through the digestive tract by keeping them soft. Soluble fiber slows the digestive process and is water-soluble. Found in beans, fruits, and oat products, it is thought to help lower blood fats and blood glucose (sugar).

Fiber is also a slender, elongated natural or synthetic filament capable of being spun into yarn, e.g., cotton.

What is Fibiger, Johannes Andreas Grib ?

Fibiger, Johannes Andreas Grib (1867–1928) was Danish Pathologist Johannes Andreas Grib Fibiger was born in Silkeborg, Denmark, on April 23, 1867, to C. E. A. Fibiger, a local medical practitioner, and Elfride Muller, a writer.

Fibiger studied under bacteriologists Robert KOCH and Emil von Behring, and from 1891 to 1894 he was assistant to Professor C. J. Salomonsen at the department of bacteriology at the University of Copenhagen. He received his doctorate from the University of Copenhagen in 1895 based on research into the bacteriology of diphtheria.

He was appointed prosector at the university’s Institute of Pathological Anatomy (1897–1900), principal of the Laboratory of Clinical Bacteriology of the Army (1890–1905), and in 1905 became the director of the central laboratory of the army and consultant physician to the Army Medical Service.

Fibiger’s early research dealt with diphtheria and tuberculosis, and he developed laboratory methods for growing the causing bacteria as well as a serum to protect against the disease. Fibiger achieved the first controlled induction of cancer in laboratory animals, after research in studying tumors in the stomachs of animals, by feeding mice and rats with cockroaches infected with a worm. His work led others to pursue the research on chemical carcinogens and led to the development of modern cancer research.

Fibiger was a founding member and joint editor of the Acta Pathologica et Microbiologica Scandinavica, and coeditor of Ziegler’s Beiträge zur pathologischen Anatomie und zur allgemeinen Pathologie. He received the 1927 Nobel Prize in physiology or medicine for his work on cancer, specifically for his “discovery of the Spiroptera carcinoma.” Fibiger died on January 30, 1928, in Copenhagen.

What is fibril ?

A small or microscopic thread of cellulose that is part of the cellulose matrix of plant cell walls. The contractile unit of a muscle cell or a bundle of filaments in a striated muscle cell; the thin fibrous structure of a nerve; a long fine hair or fiber; many fibrils bundle together to form a fiber. Makes up the smallest unit of paper fibers. Also a linear feature in the H alpha chromosphere of the Sun, found near strong sunspots and plages or in filament channels. Fibrils parallel strong magnetic fields.

What is fibroblast (fibrocyte) ?

A flat, elongated, branched, irregular and motile cell type found in vertebrate connective tissue that produces extracellular collagen and elastin fibers; spindlelike with long cytoplasmic extensions at each end and with oval, vesicular nuclei; most abundant cell type found in the skin. Fibroblasts differentiate into chondroblasts that secrete cartilage matrix, collagenoblasts that proliferate at chronic inflammation sites, and osteoblasts that secrete bone matrix. They form the fibrous tissues in the body, tendons, and aponeuroses, the shiny, broad sheets of connective tissue that bind muscle fibers together to form muscles, as well as supporting and binding tissues.

What is fight-or-flight reaction ?

The reaction in the body when faced with a sudden and unexpected threat or stress. The reaction is immediate to either run or stay and fight. In humans, a sudden release of the hormones epinephrine and norepinephrine increases blood flow to the muscles and increases blood pressure. The resulting increase in muscle strength and mental ability prepares the body for either reaction that is chosen. In other animals such as the wood thrush (Hylocichla mustelina), flight is preferred over fight.

What is filial generation (offspring generation) ?

The successive generations of progeny in a controlled series of crosses, beginning with two specific parents (the P generation), and intercrossing the progeny of each new generation. F1 is the first offspring or filial generation between any two parents, the first generation of descent; F2 is the second (grandchildren); and so on.

What is filter feeding ?

The filtering of suspended food particles from a water current by using gill rakers or similar organs.

What is fingerprinting ?

In genetics, the identification of multiple specific alleles on a person’s DNA to produce a unique identifier for that person; used in forensics. There are six steps to DNA fingerprinting. First the DNA must be isolated and removed from the cells of the animal or plant. Then special enzymes, called restriction enzymes, are used to cut the DNA at specific places, and the DNA are sorted by size. The DNA pieces are then transferred to a nylon sheet, which is then probed. The fingerprint is generated by adding tagged probes to the nylon sheet, and each probe sticks in only one or two specific places, wherever the sequences match. The final DNA fingerprint is created by using several different probes, with the resulting end product looking like a grocery store bar code. DNA fingerprinting is increasingly being used in criminal cases, and people have been freed from prison based on DNA fingerprinting.

Who was Finsen, Niels Ryberg ?

Finsen, Niels Ryberg (1860–1904) Danish Physician Niels Ryberg Finsen was born on December 15, 1860, in the capital city Thorshavn in the Faroe Islands (Denmark) to Johanne Fröman and Hannes Steingrim Finsen, an Icelandic family that could trace its ancestry back to the 10th century and occupied many of the highest positions in the administration of the Faroe Islands. He received his early education in schools at Thorshavn and then at Herlufsholm in Denmark.

In 1882 Finsen went to Copenhagen to study medicine. After taking his final examination in 1890, he became prosector of anatomy at the University of Copenhagen until 1893. He continued with private tutoring of medical students to make a moderate income.

By 1883 he was diagnosed with Pick’s disease, characterized by progressive thickening of the connective tissue of certain membranes in the liver, the heart, and the spleen, with long-term impairment of the functions of these organs. He also developed symptoms of heart trouble and ascites, and became more and more of an invalid until finally during his last years he was confined to a wheelchair. It did not prevent him from making contributions to medicine.

He was instrumental in discovering the effects of light—and in particular ultraviolet light (then called red light)—as phototherapy against diseases such as lupus vulgaris in 1893. In 1895 he made a great breakthrough that established his international reputation by introducing the revolutionary carbon-arc treatment (Finsen’s therapy) of lupus. In 1896 he founded the Finsen Medical Light Institute (now the Finsen Institute) in Copenhagen.

He received the Nobel Prize in physiology or medicine on December 10, 1903, for his work in treating diseases with light.

Among the many publications by Finsen, two are especially noteworthy: Om Lysets Indvirkninger paa Huden (On the effects of light on the skin) appeared in 1893, and the classical treatise Om Anvendelse i Medicinen af koncentrerede kemiske Lysstraaler (The use of concentrated chemical light rays in medicine) was published in 1896. The results of much of his research are contained in the communications published by his institute. Finsen tried to combat his illness in various ways, including keeping a diet poor in salt during his last years. This led to his last publication, a thorough study of En Ophobning af Salt i Organismen (An accumulation of salt in the organism) in 1904. ?

In 1899 he became Knight of the Order of Dannebrog, and a few years later the Silver Cross was added. He was a member or honorary member of numerous societies in Scandinavia, Iceland, Russia, and Germany. He received a Danish gold medal for merit, and in 1904 the Cameron Prize was given to him from the University of Edinburgh.

In 1892 Finsen married Ingeborg Balslev, the daughter of Bishop Balslev at Ribe. They had four children. Finsen died on September 24, 1904.

What is firefly ?

Commonly called a lightning bug, they are neither flies nor bugs. They belong to the order Coleoptera, family Lampyridae, which are beetles. These small flying beetles produce their own light, from a chemical called luciferase, from structures in their abdomen. Females of some species, which are wingless, and many larvae also produce light and are called glowworms. Fireflies can be seen in early summer (late May), appearing at dusk. Males and females attract each other with a flashing green light in their abdomens. The wingless females flash from the ground and the males look for them. There are more than 2,000 species of firefly in temperate and tropical environments worldwide.

What is first law of thermodynamics ?

Simply put, energy can neither be created nor destroyed, only transformed or transferred from one molecule to another; in effect, the total amount of energy in the universe is constant. Also known as the Law of Conservation of Energy. Thermodynamics is the study of the conversion of energy between heat and other forms, e.g., mechanical.

What is fission (binary fission) ?

Asexual reproduction or division of a single-celled individual, such as a prokaryote, into two new single-celled individuals of equal size and genetic composition, without mitosis occurring. From the Latin fissilis, meaning “easily split.”

What is fixation ?

The complete prevalence of one gene form (allele), resulting in the total exclusion of the other. Genes that confer a reproductive advantage generally go to fixation.

What is fixed action pattern (FAP) ?

A series of innate behavior patterns (a fixed action) in response to a specific stimulus (called a sign stimulus or innate releaser) that continues until the response is completed. FAPs are genetic and not individually learned. For example, a group of spined larvae of the buck moth (Hemileuca maia) will all instantly raise their bodies and thrash back and forth when a predator (bird) approaches.

What is flaccid ?

Limp, soft condition, e.g., walled cells are flaccid in isotonic surroundings; low turgid pressure; opposite of turgid.

What is flagellum ?

A long whiplike structure that is used to propel certain kinds of prokaryote and eukaryote cells. The cells can have an individual flagellum or a few flagella per cell. In prokaryote organisms the flagellum is composed of a protein called flagellin. In the eukaryote organism, it is longer than a CILIUM but has the same construction of nine outer double microtubules and two inner single microtubules.

What is flanking region ?

The DNA sequences extending on either side of a specific gene or locus; a region preceding or following the transcribed region. The 3’ flanking region (downstream flanking region) is found immediately distal (distant) to the part of a gene that specifies the mRNA and where a variety of regulatory sequences are located. The 3’ flanking region often contains sequences that affect the formation of the 3’ end of the message and may contain enhancers or other sites to which proteins may bind. The 5’ flanking region flanks the position that corresponds to the 5’ end of the mRNA and is that part of DNA that precedes the transcription-start site for a particular gene. The 5’ flanking region contains the promoter (transcription control region) and other enhancers or protein binding sites.

What is flatworms ?

Organisms that comprise the phylum Platyhelminthes. These are normally hermaphroditic organisms that have flat bodies and are bilaterally symmetrical, with defined head and tail, centralized nervous system, and eyespots (light-sensitive cells). They include flukes (trematodes), tapeworms (Cestoda), and free-living flatworms (Turbellaria), and it is estimated that more than 20,000 species exist. Millions of humans are host to these parasites.

What is flavin ?

A PROSTHETIC GROUP found in flavoproteins and involved in biological oxidation and reduction. Forms the basis of natural yellow pigments like riboflavin.

What is flea ?

A major group of bloodsucking insects that feed on animals, belonging to the order Siphonaptera. There are about 2,000 known species existing on all continents. Some species are vectors for diseases. They are wingless, flattened-body types with legs with long claws. They can jump from 14 to 16 inches.

While they tend to be associated with pets such as cats and dogs (Ctenocephalides canis [dog flea] and Ctenocephalides felis [cat flea]), they do include humans as hosts.

Who was Fleming, Sir Alexander ?

Fleming, Sir Alexander (1881–1955) was British Bacteriologist Sir Alexander Fleming was born on a farm at Lochfield near Darvel in Ayrshire, Scotland, on August 6, 1881. He attended Louden Moor School, Darvel School, and Kilmarnock Academy before moving to London, where he attended the Polytechnic Institute. He spent four years in a shipping office before entering St. Mary’s Medical School, London University, where he received an M.B., B.S., with gold medal in 1908, and became a lecturer at St. Mary’s until 1914, when he served during World War I, returning to St. Mary’s in 1918. He was elected professor of the school in 1928 and emeritus professor of bacteriology, University of London, in 1948.

Fleming was interested in the natural bacterial action of the blood and in antiseptics, and he worked on antibacterial substances that would not be toxic to animal tissues. In 1921 he discovered an important bacteriolytic substance that he named lysozyme. In 1928 he made his most important discovery while working on an influenza virus. He noticed that mold had developed accidentally on a staphylococcus culture plate and that the mold had created a bacteria-free circle around itself. Further experiments found that a mold culture prevented growth of staphylococci, even when diluted 800 times. He named the active substance penicillin.

Sir Alexander wrote numerous papers on bacteriology, immunology, and chemotherapy, including original descriptions of lysozyme and penicillin. He was the recipient of numerous awards and honors in scientific societies worldwide. Fleming shared the Nobel Prize in physiology or medicine in 1945 with Ernst Boris CHAIN and Howard Walter FLOREY, who both (from 1939) carried Fleming’s basic discovery forward in the isolation, purification, testing, and quantity production of penicillin. Fleming died on March 11, 1955, and is buried in St. Paul’s Cathedral.

What is flicker fusion rate ?

The rate beyond which the human eye can no longer recognize discontinuous changes in brightness as a flicker, i.e., the rate is the frequency at which the “flicker” of an image cannot be distinguished as an individual event. The flicker fusion rate (FFR) is 31.25 Hz, or 60 frames per second (bright light) and 24 frames per second (dim light) in humans. When a frame rate is above this number, the eye sees the signal as a consistent image (as on television). A fly has an FFR of 300 frames per second.

What is flora ?

The term for all plants in a given location or, collectively, on the planet.

Who was Florey, Sir Howard Walter ?

Florey, Sir Howard Walter (1898–1968) Australian Pathologist Sir Howard Walter Florey was born on September 24, 1898, in Adelaide, South Australia, to Joseph and Bertha Mary Florey. His early education was at St. Peter’s Collegiate School, Adelaide, and then Adelaide University, where he graduated M.B., B.S., in 1921. He was awarded a Rhodes Scholarship to Magdalen College, Oxford, leading to the degrees of B.Sc. and M.A. in 1924. He then attended Cambridge as a John Lucas Walker student.

In 1925, he visited the United States on a Rockefeller traveling fellowship for a year, returning in 1926 to a fellowship at Gonville and Caius College, Cambridge, receiving a Ph.D. in 1927. At this time he also held the Freedom Research Fellowship at the London Hospital. In 1927, he was appointed Huddersfield Lecturer in Special Pathology at Cambridge. In 1931 he succeeded to the Joseph Hunter Chair of Pathology at the University of Sheffield.

In 1935 he became professor of pathology and a fellow of Lincoln College, Oxford. He was made an honorary fellow of Gonville and Caius College, Cambridge, in 1946, and an honorary fellow of Magdalen College, Oxford, in 1952. From 1945 to 1957 he was involved in the planning of the John Curtin School of Medical Research in the new Australian National University. In 1962 he was made provost of Queen’s College, Oxford.

During World War II he was appointed honorary consultant in pathology to the army, and in 1944 he became Nuffield visiting professor to Australia and New Zealand.

His collaboration with Ernst Boris CHAIN, which began in 1938, led to the systematic investigation of the properties of naturally occurring antibacterial substances. Lysozyme, an antibacterial substance found in saliva and human tears, discovered by Sir Alexander FLEMING, was their original interest, but they moved to substances now known as antibiotics. The work on penicillin was a result.

In 1939 Florey and Chain headed a team of British scientists, financed by a grant from the Rockefeller Foundation, whose efforts led to the successful small-scale manufacture of penicillin. They showed that penicillin could protect against infection but that the concentration of penicillin in the human body— and the length of time of treatment—were important factors for successful treatment. In 1940 a report was issued describing how penicillin had been found to be a chemotherapeutic agent capable of killing sensitive germs in the living body. An effort was made to create sufficient quantities for use in World War II to treat war wounds, and it is estimated to have saved thousands of lives. In 1945 Florey was awarded a Nobel Prize in medicine with Alexander Fleming and Ernst Chain.

Florey was a contributor to and editor of Antibiotics (1949). He was also coauthor of a book of lectures on general pathology and has had many papers published on physiology and pathology.

In 1944 he was created a knight bachelor. When a life peerage was conferred on him in 1965, he chose to be styled Lord Florey of Adelaide and Marston. He was provost of Queen’s College, Oxford, from 1962 until he died on February 21, 1968.

What is flower ?

The reproductive part of a plant. Can be both male and female, producing both pollen and ovule. Flowers are the most commonly used part in identifying a plant and are often showy and colorful.

What is fluid feeder ?

An animal that lives by sucking nutrientrich fluids from another living organism. The two main ways to fluid-feed are piercing and sucking, and cutting and licking. Examples of insects that pierce and suck are platyhelminths, nematodes, annelids, and arthropods, which all have distinct mouth parts that bore into their prey and then suck out the prey’s body fluids with a pharynx. Secreted enzymes help aid in the digestion of the fluids. Piercing by insects typically involves the use of a proboscis formed by the maxillae and composed of two canals. The first canal carries in the prey’s blood, and the other delivers saliva and anticoagulants.

The cutting-and-licking technique is used by black flies and vampire bats, who cut the prey’s body with teeth or sharp mouthparts and then lick the fluids while injecting anticoagulants to prevent clotting.

What is fluid mosaic model ?

The model proposes that a plasma membrane surrounds all cells and is composed of about half lipids, mostly phospholipids and cholesterol, and half proteins, with the proteins and phospholipids floating around the membrane in constant motion unless they bind to something. By being fluid, the lipid molecules can move to open up as a channel whereby substances can enter or leave. The protein molecules in the membrane act as carrier, channel, or active transport mechanisms for larger molecules that must enter or leave the cell.

What is fluke ?

An organism belonging to the phylum Platyhelminthes, a flatworm of the class Trematoda. Flukes are flat, unsegmented, and parasitic. Two orders exist, the Mongenea (monogenetic flukes) and Digenea (digenetic flukes). Humans become hosts for Schistosoma mansoni (human blood fluke) and Fasciola hepatica (sheep liver fluke).

What is folate coenzymes ?

A group of heterocyclic compounds that are based on the 4-(2-amino-3,4-dihydro4-oxopteridin-6-ylmethylamino) benzoic acid (pteroic acid) and conjugated with one or more L-glutamate units. Folate derivatives are important in DNA synthesis and erythrocyte formation. Folate deficiency leads to ANEMIA.

What is folivore ?

An animal whose primary source of food is foliage. For example, the larvae of the buck moth (Hemileuca maia [Drury]) eats only the leaves of oak, favoring scrub, live, blackjack, and post oaks; the Karner blue butterfly (Lycaeides melissa samuelis) larvae feed only on the leaves of wild blue lupine (Lupinus perennis).

What is follicle ?

Any enclosing cluster or jacket of cells, or a small sac or pore, that protects and nourishes within it a cell or structure. A fluid-filled follicle in the ovary harbors the developing egg cell. When the follicle ruptures (ovulation), an egg is released. A hair follicle envelops the root of hair.

What is Food and Drug Administration (FDA) ?

A U.S. federal agency responsible for regulating the development, use, and safety of drugs, medical devices, food, cosmetics, and related products.

The U.S. Food and Drug Administration is a scientific, regulatory, and public health agency that oversees items accounting for 25 cents of every dollar spent by consumers. Its jurisdiction encompasses most food products (other than meat and poultry); human and animal drugs; therapeutic agents of biological origin; medical devices; radiation-emitting products for consumer, medical, and occupational use; cosmetics; and animal feed. The agency grew from a single chemist in the U.S. Department of Agriculture in 1862 to a staff of approximately 9,100 employees and a budget of $1.294 billion in 2001, comprising chemists, pharmacologists, physicians, microbiologists, veterinarians, pharmacists, lawyers, and many others. About onethird of the agency’s employees are stationed outside of the Washington, D.C., area, staffing over 150 field offices and laboratories, including five regional offices and 20 district offices. Agency scientists evaluate applications for new human drugs and biologics, complex medical devices, food and color additives, infant formulas, and animal drugs. Also, the FDA monitors the manufacture, import, transport, storage, and sale of about $1 trillion worth of products annually at a cost to taxpayers of about $3 per person. Investigators and inspectors visit more than 16,000 facilities a year and arrange with state governments to help increase the number of facilities checked.

What is food chain ?

The energy path in a community by way of food from those who produce it to those that feed on them. For example, plants are eaten by herbivores that are eaten by carnivores. Food chains that are interconnected are called food webs.

What is forensics ?

The use of social and physical sciences to combat crime, e.g., the science of using DNA for identification. It has been used to identify victims; establish paternity in child-support cases; and prove the presence of a suspect at a crime scene. Forensic science can be used for issues from burglary to environmental protection.

What is formula ?

An exact representation of the structure of a molecule, ion, or compound showing the proportion of atoms that compose the material, e.g., H2O.

Who was Forssmann, Werner Theodor Otto

Forssmann, Werner Theodor Otto (1904–1979) was German Surgeon Werner Theodor Otto Forssmann was born in Berlin on August 29, 1904, to Julius Forssmann and Emmy Hindenberg. He was educated at the Askanische Gymnasium (secondary grammar school) in Berlin. In 1922 he went to the University of Berlin to study medicine, passing his state examination in 1929. For his clinical training he attended the University Medical Clinic and in 1929 went to the August Victoria Home at Eberswalde near Berlin.

He developed the first technique for the catheterization of the heart by inserting a cannula into his own antecubital vein, through which he passed a catheter for 65 cm. He then walked into the X-ray department to have a photograph taken of the catheter lying in his right auricle. He abandoned cardiology after being ridiculed for this act. André F. Cournand and Dickinson W. Richards perfected this procedure. He was appointed chief of the surgical clinic of the city hospital at Dresden-Friedrichstadt and at the Robert Koch Hospital, Berlin. During World War II he became a prisoner of war until his release in 1945, when he went into practice with his wife. Beginning in 1950 he practiced as a urological specialist at Bad Kreuznach. In 1958 he was chief of the surgical division of the Evangelical Hospital at Düsseldorf until 1970.

What is In 1956 he was awarded, together with André COURNAND and Dickinson W. RICHARDS, the Nobel Prize in physiology or medicine for their work in development of cardiac catheterization. He was also appointed honorary professor of surgery and urology at the Johannes Gutenberg University, Mainz. He was awarded many honors and belonged to a number of scientific organizations during his career. He died on June 1, 1979, in Schopfheim, in the Black Forest in West Germany. ?

What is fossil ?

Preserved remains or imprints of once-living plants or animals or their tracks, or burrows, or products (e.g., dung).

What is founder effect ?

When a small population migrates from a larger population, becomes isolated, and forms a new population, the genetic constitution of the new population is that of a few of the pioneers, not the main population source; the genetic drift observed in a population founded by a small nonrepresentative sample of a larger population; it is the difference between the gene pool of a population as a whole and that of a newly isolated population of the same species.

What is fragile X syndrome ?

It is the most common form of genetically inherited mental retardation. Named for its association with a malformed X chromosome tip, the frequency of the syndrome is greater in males than in females, occurring in approximately 1 in 1,000 male births and 1 in 2,500 female births. In 1991 the causative gene FMR-1 (fragile X mental retardation) was discovered. Fragile X is the most common inherited cause of learning disability and affects boys and girls of all ethnic groups.

What is fragmentation ?

A mechanism of asexual reproduction in which the parent plant or animal separates into parts that re-form whole organisms.

What is frameshift mutation ?

A mutation via an addition of a pair or pairs of nucleotides that changes the codon reading frame of mRNA by inserting or deleting nucleotides.

What is fraternal ?

In offspring, twins that are not identical. Identical twins occur when both fetuses come from the division of a single fertilized egg and have separate placentas. Fraternal twins can be either same or opposite sex.

What is free energy ?

Energy readily available for producing change in a system.

What is free radical ?

A molecule that contains at least one unpaired electron; highly reactive chemical that usually exists only for a short time. Formed in the body during oxidation, a normal by-product of metabolism, they can bind with electrons from other molecules and can cause cellular damage by disrupting normal cellular processes, but can be kept in check by antioxidants such as certain enzymes or vitamins (C and E).

What is freshwater ?

The Earth is mostly water, which covers 74 percent of its surface. Freshwater accounts for only 3 percent of the total water. Freshwater is water that contains less than 1,000 milligrams per liter (mg/L) of dissolved solids. The United States Geological Survey (USGS) states that, generally, more than 500 mg/L of dissolved solids is undesirable for drinking and many industrial uses.

Who was Fritts, Harold Clark ?

Fritts, Harold Clark (1928– ) was American Botanist, Dendrochronologist Harold Fritts was born on December 17, 1928, in Rochester, New York, to Edwin C. Fritts, a physicist at Eastman Kodak Company, and Ava Washburn Fritts. As a young boy he was interested in natural history and weather and even had a subscription to daily weather maps. Along with his maps, he constructed a weather vane that read out wind directions in his room. Fritts attended Oberlin College in Oberlin, Ohio, from 1948 to 1951 and received a B.A. in botany. From 1951 to 1956 he attended Ohio State University in Columbus and received an M.S. in botany in 1953 and a Ph.D. in 1956.

Fritts made major contributions in understanding how trees respond to daily climatic factors and how they record that information in ring structure. He developed a method to statistically record a tree’s response to changes in climate. Using that information he developed a method to reconstruct climate from past tree rings and to reconstruct spatial arrays of past climate from spatial arrays of tree-ring data. He also developed a biophysical model of tree-ring structure response to daily weather conditions. This work has laid the groundwork for much current dendroclimatic reconstruction work.

Fritts authored nearly 60 pioneering scientific papers on dendrochronology, including the bible of the field, Tree Rings and Climate in 1976, one of the most cited books on the subject. In 1965 he was elected a fellow in the American Association for the Advancement of Science. He received a John Simon Guggenheim fellowship in botany in 1968. In 1982 he was given the Award for Outstanding Achievement in Bioclimatology from the American Meteorological Society, and in 1990 he received the Award of Appreciation from the dendrochronological community, in Lund, Sweden.

Fritts pioneered the understanding of the biological relationships and reconstruction of past climate from tree-ring chronologies. He currently is engaged in some scientific writing and is finishing work on the tree ring model.

What is frond ?

The leaf of a fern or palm. Consists of the stipe (petiole or stalk of the fruiting body) and blade, the expanded portion of the frond. Also used to describe the main part of a kelp plant.

What is frugivore ?

An organism that generally eats fruits, e.g., the fruit bat.

What is fruit ?

A mature or ripened ovary or cluster of ovaries in a flower.

What is fruiting body ?

The organ in which meiosis occurs and sexual spores are produced in fungi and mycobacteria. They are distinct in size, shape, and coloration for each species.

What is functional group ?

Organic compounds are thought of as consisting of a relatively unreactive backbone, for example a chain of sp3 (three p orbitals with the s orbital) hybridized carbon atoms, and one of several functional groups. The functional group is an atom, or a group of atoms, that has similar chemical properties whenever it occurs in different compounds. It defines the characteristic physical and chemical properties of families of organic compounds.

What is Fungi ?

A kingdom of heterotrophic, single-celled, multinucleated, or multicellular organisms that include yeasts, molds, and mushrooms; organisms that lack chlorophyll, cannot photosynthesize, and get their nutrients directly from other organisms by being parasites or from dead organic matter, acting as saprophytes. Molds, yeasts, mildews, rusts, smuts, and mushrooms are all fungi. Fungi have a true nucleus enclosed in a membrane and chitin in the cell wall. There are about 8,000 fungi known to attack plants. Some fungi are pathogenic to humans and other animals. Some molds, in particular, release toxic chemicals called mycotoxins that can result in poisoning or death.

What is fur (ferric uptake regulator) ?

The iron uptake regulating protein present in PROKARYOTEs, which binds simultaneously Fe and DNA, thereby preventing the biosynthesis of ENZYMEs for the production of SCAVENGER chelates (SIDEROPHOREs).