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BAILE INoLVIDABLE
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Chapter 4 Skin and Body Membranes Body Membranes Functions of body membranes Cover body surfaces Line body cavities Form protective sheets around organs Classified according to tissue types Body Membranes Two major categories Epithelial membranes Cutaneous membranes Mucous membranes Serous membranes Connective tissue membranes Synovial membranes Epithelial Membranes Epithelial membranes are simple organs Also called covering and lining membranes These membranes contain both: Epithelial tissue layer Connective tissue layer Epithelial Membranes Cutaneous membrane = skin Dry membrane Outermost protective boundary Consists of two layers Epidermis is composed of keratinized stratified squamous epithelium Dermis is mostly dense (fibrous) connective tissue Epithelial Membranes • Mucous membranes (mucosae) • I Moist membranes Some mucosae secrete protective, lubricating mucus Line all body cavities that open to the exterior body surface • Adapted for absorption or secretion • ' Consists of two layers • Epithelium type depends on site • Loose connective tissue (lamina propria) Epithelial Membranes Serous membranes (serosae) Line compartments in the ventral body cavity that are ciosed to the exterior of the body Occur in pairs, separated by serous fluid, with a visceral and parietal layer Consists of two layers Simple squamous epithelium Areolar connective tissue Epithelial Membranes Specific serous membranes Peritoneum Cover organs in the abdominal cavity Pleurae Surround the lungs Pericardia Surround the heart Connective Tissue Membranes Synovial membranes Loose areolar connective tissue only (no epithelial tissue) Line fibrous capsules surrounding joints Line bursae Line tendon sheaths Secrete a lubricating fluid to cushion organs moving against each other during muscle activity Integumentary System Integumentary system consists of the: Skin (cutaneous membrane) Skin appendages Sweat glands Oil glands Hair Nails Functions of the Integumentary System Insulates and cushion deeper body organs Protects the entire body from: Mechanical damage (bumps and cuts) Chemical damage (acids and bases) Thermal damage (heat or cold) Ultraviolet (UV) radiation (sunlight) Microbes (bacteria) • Water loss Functions of the Integumentary System Regulates heat loss as controlled by the nervous system Acts as a mini-excretory system; sweat aids in the loss of Urea Salts Water Synthesizes vitamin D Secretions create a protective acid mantle Structure of the Skin Two kinds of tissue compose the skin Epidermis Dermis Subcutaneous tissue (hypodermis) Anchors the skin to underlying organs Not technically part of the integumentary system Composed mostly of adipose tissue Serves as a shock absorber and insulates deeper tissues Structure of the Skin Epidermisouter layer Composed of stratified squamous epithelium Most cells are keratinocytes which produce a fibrous protein called keratin Keratinization makes the epidermis tough Desmosomes connect keratinocytes together Avascular Composed of five layers (strata) Structure of the Skin Summary of strata (layers) of the epidermis from deepest to most superficial Stratum basale Stratum spinosum Stratum granulosum Stratum lucidum (thick, hairless skin only) Stratum corneum Structure of the Skin Stratum basale (stratum germinativum) Deepest layer of epidermis Lies next to dermis Wavy borderline with the dermis anchors the two together Cells undergoing mitosis Daughter cells are pushed upward to become the more superficial layers Stratum spinosum Cells become increasingly flatter and more keratinized Structure of the Skin Stratum granulosum Stratum lucidum Formed from dead cells of the deeper strata Occurs only in thick, hairless skin of the palms of hands and soles of feet Stratum corneum Outermost layer of epidermis Shingle-like dead cells are filled with keratin (protective protein prevents wat loss from skin Structure of the Skin Melanin Melanin is a pigment produced by melanocytes Melanocytes are mostly in the stratum basale of the epidermis Color is yellow to brown to black Structure of the Skin Epidermal dendritic cells Alert and activate immune cells to a threat (bacterial or viral invasion) Merkel cells Associated with sensory nerve endings Serve as touch receptors called Merkel discs Structure of the Skin Dermis Connective tissue Underlies the epidermis Two regions Papillary Reticular Structure of the Skin Two regions of the dermis Papillary layer (upper dermal region) contain projections called dermal papillae Areolar connective tissue Indent the epidermis above Many projections contain capillary loops, and others house pain and touch receptors On palm and sole surfaces, papillae increase friction and gripping ability Fingerprints are identifying films of sweat Structure of the Skin Two regions of the dermis Reticular layer (deepest skin layer) Dense irregular connective tissue Blood vessels Sweat and oil glands Deep pressure receptors (lamellar corpuscles) Structure of the Skin Other dermal features Cutaneous sensory receptors Phagocytes Collagen and elastic fibers Blood vessels I Nerve supply Skin Color • Three pigments contribute to skin color 1. Melanin • Yellow, reddish brown, or black pigments 2. Carotene • Orange-yellow pigment (also found in some vegetables) 3. Hemoglobin Red coloring from blood cells in dermal capillaries Oxygen content determines the extent of red coloring Skin Color Redness (erythema) due to embarrassment, inflammation, hypertension, fever, or allergy Pallor (blanching) due to emotional stress (such as fear), anemia, low blood pressure, impaired blood flow to an area Jaundice (yellow cast)-indicates a liver disorder • Bruises (black and blue marks)-hematomas Appendages of the Skin Cutaneous glands are all exocrine glands Sebaceous glands Sweat glands Hair and hair follicles Nails Appendages of the Skin Sebaceous (oil) glands Located all over the skin except for palms and soles Produce sebum (oil) Makes skin soft and moist Prevents hair from becoming brittle Kills bacteria Most have ducts that empty into hair follicles; others open directly onto skin surface Glands are activated at puberty with increased androgens Appendages of the Skin Sweat (sudoriferous) glands Produce sweat Widely distributed in skin Two types of sudoriferous glands Eccrine glands Apocrine glands Appendages of the Skin Eccrine glands More numerous, located all over the body Open via duct to sweat pores on the skin's surface Produce acidic sweat Water, salts, vitamin C, traces of metabolic waste Function in body temperature regulation Appendages of the Skin Apocrine glands Ducts empty into hair follicles in the armpit and genitals Begin to function at puberty Release sweat that also contains fatty acids and proteins (milky or yellowish color) • Play a minimal role in body temperature regulation Appendages of the Skin Hair Located body-wide except for palms, soles, nipples, lips Produced by hair follicle Root is enclosed in the follicle Shaft projects from the surface of the scalp or skin Consists of hard keratinized epithelial cells Melanocytes provide pigment for hair color Hair grows in the matrix of the hair bulb in stratum basale Appendages of the Skin Hair anatomy Central medulla Cortex surrounds medulla Cuticle on outside of cortex Most heavily keratinized region of the hair Melanin provides color Appendages of the Skin Associated hair structures Hair follicle Composed of an inner epithelial root sheath andan outer fibrous sheath Dermal region provides a blood supply to the hair bulb (deepest part of the follicle) Arrector pili muscle connects to the hair follicle to pull hairs upright when we are cold or frightened Appendages of the Skin Nails Heavily keratinized, scalelike modifications of the epidermis Stratum basale extends beneath the nail bed, which is responsible for growth Lack of pigment makes nails colorless Appendages of the Skin Parts of a nail Free edge Body is the visible attached portion Nail folds are skin folds that overlap the edges of the nail; the cuticle is the proximal edge Root of nail is embedded in skin Growth of the nail occurs from nail matrix of nail bed Homeostatic Imbalances of Skin Infections and allergies Athlete's foot Caused by fungal infection (Tinea pedis) Itchy, red peeling skin between the toes Boils (furuncles) and carbuncles Caused by inflammation of hair follicles Carbuncles are clusters of boils caused by bacteria Cold sores (fever blisters) Caused by human herpesvirus 1 Blisters itch and sting Homeostatic Imbalances of Skin Infections and allergies Contact dermatitis Caused by exposure to chemicals that provoke allergic responses Itching, redness, and swelling of the skin Impetigo Caused by bacterial infection Pink, fluid-filled raised lesions around mouth/nose Psoriasis Triggered by trauma, infection, hormonal changes, or stress Red, epidermal lesions covered with dry, silvery scales that itch, burn, Crack, or sometimes bleed Homeostatic Imbalances of Skin • Burns Tissue damage and cell death caused by heat, electricity, UV radiation, or chemicals Associated dangers Protein denaturation and cell death Dehydration and electrolyte imbalance Circulatory shock Result in loss of body fluids and infection from the invasion of bacteria Homeostatic Imbalances of Skin Extent of a burn is estimated using the rule of nines Body is divided into 11 areas for quick estimation Each area represents about 9 percent of total body surface area The area surrounding the genitals (the perineum) represents 1 percent of body surface area Homeostatic Imbalances of Skin . First-degree burn (superficial burn) Only epidermis is damaged Skin is red and swollen Second-degree burn (superficial partial-thickness burn) Epidermis and superficial part of dermis are damaged Skin is red, painful, and blistered Regrowth of the epithelium can occur Homeostatic Imbalances of Skin Third-degree burn (full-thickness burn) Destroys epidermis and dermis; burned area is painless Requires skin grafts, as regeneration is not possible Burned area is blanched (gray-white) or black Fourth-degree burn (full-thickness burn) Extends into deeper tissues (bone, muscle, tendons) Appears dry and leathery Requires surgery and grafting May require amputation Homeostatic Imbalances of Skin Criteria for deeming burns critical (if any one is met): Over 30 percent of body has second-degree burns Over 10 percent of the body has third-or fourth-degree burns Third-or fourth-degree burns of the face, hands, feet, or genitals Burns affect the airways Circumferential (around the body or limb) burns have occurred Homeostatic Imbalances of Skin Skin cancer Most common form of cancer in humans Most important risk factor is overexposure to ultraviolet (V) radiation in sunlight and tanning beds Cancer can be classified two ways Benign means the neoplasm (tumor) has not spread Malignant means the neoplasm has invaded other body areas Concept Link Recall that mitosis gone wild is the basis for cancer (Chapter 3, pp. 82-83). These cells lack normal control of cell division and divide quickly, resulting in errors during DNA replication, mitosis, or both. Cells experiencing rapid, uncontrolled growth become cancerous and can metastasize (spread) to other parts of the body. Homeostatic Imbalances of Skin . First-degree burn (superficial burn) Only epidermis is damaged Skin is red and swollen Second-degree burn (superficial partial-thickness burn) Epidermis and superficial part of dermis are damaged Skin is red, painful, and blistered Regrowth of the epithelium can occur Homeostatic Imbalances of Skin Third-degree burn (full-thickness burn) Destroys epidermis and dermis; burned area is painless Requires skin grafts, as regeneration is not possible Burned area is blanched (gray-white) or black Fourth-degree burn (full-thickness burn) Extends into deeper tissues (bone, muscle, tendons) Appears dry and leathery Requires surgery and grafting May require amputation Homeostatic Imbalances of Skin Criteria for deeming burns critical (if any one is met): Over 30 percent of body has second-degree burns Over 10 percent of the body has third-or fourth-degree burns Third-or fourth-degree burns of the face, hands, feet, or genitals Burns affect the airways Circumferential (around the body or limb) burns have occurred Homeostatic Imbalances of Skin Skin cancer Most common form of cancer in humans Most important risk factor is overexposure to ultraviolet (V) radiation in sunlight and tanning beds Cancer can be classified two ways Benign means the neoplasm (tumor) has not spread Malignant means the neoplasm has invaded other body areas Concept Link Recall that mitosis gone wild is the basis for cancer (Chapter 3, pp. 82-83). These cells lack normal control of cell division and divide quickly, resulting in errors during DNA • One or more of the ABCD characteristics is evolving Developmental Aspects of Skin and Body Membranes Lanugo, a downy hair, covers the body by the fifth or sixth month of fetal development but disappears by birth Vernix caseosa, an oily covering, is apparent at birth Milia, small white spots, are common at birth and disappear by the third week Acne may appear during adolescence Pimples, scales, and dermatitis are more common with aging skin Developmental Aspects of Skin and Body Membranes In youth, skin is thick, resilient, and well hydrated With aging, skin loses elasticity and thins Skin cancer is a major threat to skin exposed to excessive sunlight Balding (alopecia) and/or graying occurs with aging; both are genetically determined other factors that may contribute include drugs and emotional stress
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🏠 DOM — HOUSE / HOME * house — dom * apartment / flat — mieszkanie * room — pokój * door — drzwi * window — okno * wall — ściana * floor — podłoga * ceiling — sufit * stairs — schody * roof — dach * garden — ogród * balcony — balkon * garage — garaż * key — klucz * lock — zamek * furniture — meble * table — stół * chair — krzesło * lamp — lampa * light — światło * shelf — półka * wardrobe — szafa * mirror — lustro * carpet — dywan * curtain — zasłona 🛋️ SALON — LIVING ROOM * living room — salon * sofa / couch — kanapa * armchair — fotel * coffee table — stolik kawowy * TV — telewizor * remote control — pilot * bookshelf — regał na książki * fireplace — kominek * cushion — poduszka dekoracyjna * blanket — koc * rug — dywan * picture — obraz * decoration — dekoracja 🍳 KUCHNIA — KITCHEN * kitchen — kuchnia * fridge — lodówka * freezer — zamrażarka * oven — piekarnik * microwave — mikrofalówka * dishwasher — zmywarka * sink — zlew * tap / faucet — kran * cooker / stove — kuchenka * kettle — czajnik * frying pan — patelnia * pot — garnek * plate — talerz * bowl — miska * cup — filiżanka * mug — kubek * glass — szklanka * fork — widelec * knife — nóż * spoon — łyżka * teaspoon — łyżeczka * chopping board — deska do krojenia * bin / trash can — kosz na śmieci 🚿 ŁAZIENKA — BATHROOM * bathroom — łazienka * shower — prysznic * bathtub — wanna * toilet — toaleta * sink — umywalka * mirror — lustro * washing machine — pralka * towel — ręcznik * soap — mydło * shampoo — szampon * toothbrush — szczoteczka do zębów * toothpaste — pasta do zębów * toilet paper — papier toaletowy * hair dryer — suszarka do włosów * comb — grzebień * brush — szczotka * razor — maszynka do golenia 🍎 JEDZENIE — FOOD * food — jedzenie * bread — chleb * butter — masło * cheese — ser * ham — szynka * egg — jajko * meat — mięso * chicken — kurczak * beef — wołowina * pork — wieprzowina * fish — ryba * rice — ryż * pasta — makaron * potatoes — ziemniaki * vegetables — warzywa * fruit — owoce * apple — jabłko * banana — banan * strawberry — truskawka * tomato — pomidor * cucumber — ogórek * onion — cebula * garlic — czosnek * soup — zupa * salad — sałatka * cake — ciasto * ice cream — lody * breakfast — śniadanie * lunch — lunch / obiad * dinner — obiad / kolacja * dessert — deser 👨 WYGLĄD — APPEARANCE * appearance — wygląd * tall — wysoki * short — niski * slim — szczupły * thin — chudy * overweight — z nadwagą * muscular — umięśniony * handsome — przystojny * beautiful — piękna * pretty — ładna * attractive — atrakcyjny * young — młody * old — stary / starszy * beard — broda * moustache — wąsy * blue eyes — niebieskie oczy * green eyes — zielone oczy * brown eyes — brązowe oczy * pale skin — blada skóra * tanned — opalony 💇 WŁOSY I FRYZURY — HAIR * hair — włosy * long hair — długie włosy * short hair — krótkie włosy * medium-length hair — włosy średniej długości * straight hair — proste włosy * curly hair — kręcone włosy * wavy hair — falowane włosy * thick hair — gęste włosy * thin hair — cienkie / rzadkie włosy * blonde hair — blond włosy * dark hair — ciemne włosy * brown hair — brązowe włosy * black hair — czarne włosy * red hair — rude włosy * grey hair — siwe włosy * bald — łysy * haircut — fryzura / strzyżenie * fringe / bangs — grzywka * ponytail — kucyk * bun — kok 🧠 CHARAKTER — PERSONALITY * friendly — przyjazny * nice — miły * kind — życzliwy * funny — zabawny * happy — szczęśliwy * cheerful — pogodny * calm — spokojny * shy — nieśmiały * confident — pewny siebie * brave — odważny * honest — uczciwy / szczery * helpful — pomocny * polite — uprzejmy * patient — cierpliwy * generous — hojny * hardworking — pracowity * lazy — leniwy * nervous — nerwowy * serious — poważny * rude — niegrzeczny * selfish — samolubny * talkative — rozmowny * quiet — cichy / małomówny * stubborn — uparty * responsible — odpowiedzialny 🍽️ RESTAURACJA — RESTAURANT * restaurant — restauracja * menu — menu * table — stolik * waiter — kelner * waitress — kelnerka * customer — klient * order — zamówienie / zamawiać * bill / check — rachunek * tip — napiwek * starter — przystawka * main course — danie główne * dessert — deser * drink — napój * still water — woda niegazowana * sparkling water — woda gazowana * reservation — rezerwacja * available table — wolny stolik Przydatne zdania: * A table for two, please. — Stolik dla dwóch osób, proszę. * Can I see the menu? — Czy mogę zobaczyć menu? * I’d like to order. — Chciałbym zamówić. * Can I have the bill, please? — Czy mogę prosić rachunek? * Is service included? — Czy obsługa jest wliczona? ☕ KAWIARNIA — CAFÉ * café — kawiarnia * coffee — kawa * tea — herbata * espresso — espresso * latte — latte * cappuccino — cappuccino * sugar — cukier * milk — mleko * cake — ciasto * sandwich — kanapka * takeaway — na wynos * to go — na wynos 💊 APTEKA — PHARMACY * pharmacy — apteka * pharmacist — farmaceuta * medicine — lekarstwo * tablets / pills — tabletki * painkiller — lek przeciwbólowy * prescription — recepta * cream — krem / maść * bandage — bandaż * plaster — plaster * cough — kaszel * headache — ból głowy * sore throat — ból gardła * cold — przeziębienie * fever — gorączka 🚆 POCIĄG / DWORZEC — TRAIN / RAILWAY STATION * train — pociąg * railway station / train station — dworzec kolejowy * platform — peron * ticket — bilet * ticket office — kasa biletowa * timetable — rozkład jazdy * departure — odjazd * arrival — przyjazd * delay — opóźnienie * passenger — pasażer * seat — miejsce / siedzenie * carriage — wagon * return ticket — bilet w obie strony * one-way ticket — bilet w jedną stronę * ticket machine — biletomat * luggage — bagaż 🏙️ MIASTO — CITY * city — miasto * town — miasteczko * street — ulica * road — droga * pavement / sidewalk — chodnik * crossroads / intersection — skrzyżowanie * traffic lights — światła * pedestrian crossing / crosswalk — przejście dla pieszych * road sign — znak drogowy * traffic — ruch uliczny * city center — centrum miasta * bus stop — przystanek autobusowy * station — stacja / dworzec * shop — sklep * supermarket — supermarket * bank — bank * hospital — szpital * police station — komisariat * post office — poczta * hotel — hotel * park — park * airport — lotnisko 🧭 PYTANIE O DROGĘ — DIRECTIONS * left — lewo * right — prawo * straight ahead — prosto * turn left — skręć w lewo * turn right — skręć w prawo * go straight — idź prosto * go back — wróć * cross the street — przejdź przez ulicę * at the corner — na rogu * around the corner — za rogiem * next to — obok * opposite — naprzeciwko * between — pomiędzy * behind — za * in front of — przed * near — blisko * far — daleko * on your left — po twojej lewej stronie * on your right — po twojej prawej stronie
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[Music] [Music] this is the story of the greatest scientific discovery ever the discovery that everything is made of atoms the vast variety and richness of everything we see around us in the world and beyond how it's built up how it all fits together is all down to atoms and the mysterious laws they obey as scientists delve deep into the atom it's the very part of matter they unraveled nature's most shocking secrets they had to abandon everything they believed in and create a whole new science a science that today underpins the whole of physics chemistry biology and maybe even life itself but for me the story of how humanity solved the mystery of the atom is both inspiring and remarkable it's a story of great geniuses of men and women driven by their thirst for knowledge and glory it's a story of false starts and conflicts of ambition and revelation a story that leads us through some of the most exciting and exhilarating ideas ever conceived of by the human race and for a working physicist like me it's the most important story there is [Music] [Music] on the 5th of October 1906 in a hotel room near Trieste a German science is called Ludwig Boltzmann hanged himself Boltzmann had a long history of psychological problems and one of the key factors in his depression was that he'd been vilified even ostracized for believing something that today we take for granted he believed that matter cannot be infinitely divisible into ever smaller pieces instead he argued that ultimately everything is made of basic building blocks atoms it seems incredible now that Boltzmann's revelation was so controversial but a hundred years ago arguing atoms were real was considered by most to be a waste of time although philosophers since the Greeks had speculated that the world might be made out of some kind of basic unit of matter they realized that they were far too small to see even under the most powerful microscopes speculating about them was therefore a complete waste of time but then in the middle of the 19th century whether or not the atom was real was suddenly a question of burning importance the reason was this steam by the 1850s it was changing the world it powered the mighty engines the trains the ships the factories of the Industrial Revolution so figuring out how to use it more effectively became a matter of crucial commercial political and military significance not surprisingly then it became the key question of 1965 [Music] the demand to build more powerful and efficient steam engines in turn created an urgent need to understand and predict the behavior of water and steam at high temperatures and pressures not the alts Minh and his scientific allies showed that if you imagine steam is made of millions of tiny rigid spheres atoms then you can create some powerful mathematical equations and those equations are capable of predicting the behavior esteemed with incredible accuracy but these same equations plunge Boltzmann and his fellow atomists into controversy their enemies argued that since the atoms referred to in their calculations were invisible they were merely a mathematical convenience rather than real physical objects to claim that imaginary entities were real seem presumptuous even blasphemous you see boss most critics argued that it was sacrilegious to reduce God's miraculous creation down to a series of collisions between tiny inanimate spheres Boltzmann was condemned as an irreligious materialist the tragic irony of Boltzmann's story is that when he took his own life in 1906 he was unaware that he'd been vindicated you see a year before he died a young scientist had published a paper which undeniably irrefutable proclaimed the reality of the atom you might have heard of this young scientist his name was Albert Einstein in 1905 the year before Boltzmann suicide Albert Einstein was 26 years old his brash arrogance had upset most of his professors and teachers and he was barely employable then he got his girlfriend pregnant that was followed by a hasty marriage he needed a job any job having not quite distinguished himself a university he took up a job as a patent clerk here in bern in switzerland he'd moved into the small one-bedroom Apartments on cram gasser with his young wife from a laborer despite dire personal straits the young Einstein had a burning ambition he was desperate to make his mark as a physicist and in 1905 during one miraculous year the mark he made was truly incredible having an undemanding job meant that young einstein had plenty of time on his hands both at work and here in his tiny apartment to think deep thoughts in the space of just a few months he was to publish several papers that would change science forever now everyone's heard of his theory of relativity even if they don't understand it and his paper on the nature of light was to win him the Nobel Prize a few years later but ironically it wasn't either of these two papers that had the most impact on the discovery of atoms the one that made all the difference was a short paper on how tiny grains of pollen danced in water almost 80 years earlier in 1827 a Scottish botanist called Robert Brown sprinkled pollen grains in some water and examined it through a microscope what he found was really strange because instead of the pollen grains floating gently in the water they danced around furiously almost as though they were alive now while this so called Brownian motion was strange scientists soon forgot about it they found it mundane even boring I mean who cared if the pollen giggled about in the water and what had the jiggling to do with atoms anyway for nearly 80 years brown's discovery remained a little-known scientific anomaly then Einstein changed everything in one staggering insight I Stein saw that Brownian motion was all about atoms in fact he realized that the jiggling of pollen grains in water could settle the raging debate about the reality of atoms forever his argument was simple the pollen will only jiggle if they were being jostled by something else so I said that the water must be made of tiny atoms like particles which themselves are jiggling and are continually buffeting the pollen if there were no atoms then the pollen would stay still so Boltzmann and his contemporaries had been rowing furiously about this question for nothing the answer was there all along Einstein proved that for Brownian motion to happen atoms must exist Einstein später went way beyond just verbal arguments with flawless mathematics he proved that the dance of the pollen revealed the size of the atom and it's mind-numbing ly tiny 1/10 of a millionth of a millimeter across a single human hair itself one of the narrowest things visible to the naked eye is over a million atoms wide let me put it another way there are more atoms in a single glass of water than there are glasses of water in all the oceans of the world sort of hurts your head just to think about it Einstein's paper ended the debate about whether the atom was real or not and Boltzmann had been totally vindicated the atom had to be real [Music] [Music] by the early years of the 20th century the atom had arrived scientists we'd argued that the atom was real were no longer heretics in a dramatic sudden reversal they became the new orthodoxy but they were to pay a huge price for their success before that even had a chance to congratulate each other on discovering the atom it ripped the rug out from under their feet and sent them spiraling into a bizarre and at times terrifying new world and it all kicked off here in what by 1910 was the world center for atomic physics Manchester two of the most extraordinary men in the history of science worked here in the physics departments of Manchester University between 1911 and 1916 they were Ernest Rutherford and Niels Bohr on the face of it two very different personalities and the unlikeliest of collaborators Rutherford was from a remote part of New Zealand and grew up on a farm Bohr was born in Copenhagen wealthy and erudite virtually an aristocrat Rutherford was the ultimate experimentalist he loved technology and ingenious arrangements of batteries coils magnets and radioactive rocks but he was also blessed with a profound intuition in contrast war was the ultimate theoretician to him science was about deep thought and abstract mathematics pen and paper chalk and blackboard were his tools logic was his path to truth although their approaches to their work couldn't have been any more different they had one thing in common they were prepared to ditch three centuries of scientific convention if it didn't fit what they believed to be true they were genuine revolutionaries Rutherford and Bohr were two of the most extraordinary minds ever produced by the human race but it would take every bit of their dogged tenacity and inspirational brilliance to take on the atom in 1907 ernest rutherford took over the physics departments in manchester this was a period of momentous scientific change just over ten years earlier in germany came the first demonstration of weird rays that see through flesh to reveal our bones these rays were so inexplicable scientists didn't know what to call them so they were named x-rays and a couple of years after that in Cambridge it was shown that powerful electric currents could produce strange streams of tiny glowing charged particles that were called electrons and in 1896 in Paris came the most significant discovery of all one that more than any other would unlock the secrets of the atom the metal uranium was shown to emit a strange and powerful energy that was named radioactivity it seemed straight out of science fiction radioactive metals were warm to touch they could even burn the skin and the rays could pass through solid matter as if it wasn't there it truly was a marvel of the modern age Rutherford was obsessed with radioactivity all sorts of questions plagued him how has it made why did it come in different forms how far could it travel through a vacuum or through air did it alter the materials that are encountered in Manchester together with his assistants hands Geiger of Geiger counter fame and Ernest Marsden he devised a series of experiments that would probe the Enigma of radioactivity 1909 Manchester University these are the props goldleaf Beaton said it's just a few atoms thick a movable phosphorescent screen that flashed when struck by radioactive rays and inside this box is the star attraction a tiny piece of the metal radium radium is an extraordinarily powerful source of a kind of radioactivity the Rutherford had named alpha rays they weren't really rays they were more like a steady stream of particles and radium spat up these particles like a machine gun that never ran out of bullets Rutherford set his students a simple enough task use the radium gun shoot the alpha radioactivity at the gold leaf and with the phosphorescent plate count the number of particles that come out the other side in practice that meant sitting alone in the dark and counting tiny almost invisible flashes on the phosphorescent screen it was deeply tedious but Rutherford insisted that they keep at it weeks passed and the team of researchers found nothing unusual the alpha particles seemed to punch through the gold almost as though it wasn't there very occasionally they would swerve slightly as they went through hardly front-page news now comes what must be the most consequential off-the-cuff remark in the history of science one that changed the world the story goes that Rutherford bumps into his assistant Geiger in the corridor outside the lab Geiger reported that so far they've seen nothing unusual now in response Rutherford could have easily just nodded and walked on but he didn't he later claimed that he said what he said at the time for the sheer hell of it but I don't believe him Rutherford had great scientific intuition and I think he had a hunch that something was about to happen here's what he said to Geiger tell young Marsden to go back and see if he can detect any alpha particles on the same side of the gold leaf as the radium source in other words see if any alpha particles are bouncing back now it's an extraordinary suggestion from Rutherford and one day he had no logical reason to make after all Geiger Marsden had spent weeks seeing alpha particles do nothing but streams straight through the gold leaf almost as though it wasn't there why would any bounce back the Geiger Marsden were young and in all the big New Zealand er they did their master's bidding and went back into their dark lab and watched patiently for days they saw absolutely nothing they strained their eyes to the points of myopia but didn't see a single alpha particle bouncing back off the gold it seemed that rather for suggestion really was a stupid one but then the impossible happened one afternoon in 1909 Geiger burst into Rutherford's office with some astonishing news very very occasionally an alpha particle would indeed ricochet back off the gold leaf Geiger calculated that only 1 in 8,000 alpha particles would do this it's a tiny percentage but Rutherford's mind reeled with the news he would later say it was like firing a shell at a piece of tissue paper and have it bounce back at you there and then Rutherford knew he'd struck physics cold although it would take him over a year to fully understand why the alpha particles would do this when he did he would show humanity for the first time the inside of an atom now people had barely got used to the idea that atoms existed but now Rutherford knew that this my new world 1/10 of a millionth of a millimetre across had his own internal structure within the atomic there's a sub atomic world and Ernest Rutherford believed he knew what it looked like Rutherford realized that the bouncing alpha particle revealed an atom that was totally unexpected it had no familiar analogy on earth so Rutherford looked for one in the heavens he pictured the atom as a tiny solar system electrons tiny particles of negative electricity orbit around a minut positively charged object called the nucleus [Music] Rutherford calculated that the nucleus was 10,000 times smaller than the atom itself that's why only 1 in 8,000 alpha particles bounce back they're the ones that hit the Tony nucleus by chance the rest whizzed by without hitting anything the first astonishing consequence of this idea is that Rutherford's atom is almost entirely empty space that's why nearly all the alpha particles race through the gold atoms as if there's nothing there there really is nothing there consider the bizarre implications of Rutherford's atom by imagining it on a bigger scale if the nucleus were the size of a football then the nearest electron will be an orbit half a mile away the rest of the atom will be completely empty space let me explain another way if you were to suck out all the empty space from every atom in my body then I would shrink down to a size smaller than a grain of salt of course I'd still weigh the same and if you did the same thing to the entire human race then all 6 billion of us would fit inside a single Apple the atom was unlike anything we had ever encountered before and it would only get stranger and stranger almost immediately a problem surfaced and it was a big one according to the tried and trusted science of the time the electrons should lose their energy run out of speed and spiral into the nucleus in less than a blink of an eye Rutherford's atom contradicted the known laws of science the atom didn't care that it defied scientific convention it's almost entirely empty space and it's gonna stay that way I show no signs of shrinking down to the size of a grain of salt and the earth is well the size of the earth it's not getting smaller not surprisingly all the established scientists of the day including Einstein were battled scientific ideas they put their faith in all their lives had failed completely to explain the atom the atom now required a new generation of scientists to follow in Rutherford's footsteps bold brilliant and above all young it was crucial they had no loyalty or attachment to ideas held by previous generations one of the first of this new breed was niels bohr he sailed from Denmark in 1911 and made his way it's English soil having finished his studies in Copenhagen war decided to move abroad and be at the center of the new physics the trail led you to britain manchester university ernest rutherford or made it his mission to solve the puzzles of why the atom didn't collapse and why there was so much empty space as one of the new breed of theoretical physicists he was fearless in his thinking and was prepared to abandon common sense and human intuition to find an explanation so in a leap of genius he started to look for clues about the atoms structure not by looking at matter but by examining the mysterious and wonderful nature of light our atoms and lights are clearly connected most substances glow when they're heated and for centuries people had realized that different substances glow with their own distinctive colors a bit like a signature so the green of copper the yellow of sodium and the red of lithium these colors associated with different substances are called spectra and Bohr's great insights was to realize that spectra are telling us something about the inner structure of the atom that they could explain all that empty space Bohr's idea was to take Rutherford's solar system model of the atom and replace it with something that's almost impossible to imagine or visualize so sensible ideas like empty space and particles moving around in orbits fade away and they're replaced with something that is one of the most misunderstood and misused concepts in the whole of science the quantum jump now it takes most working physicists many years to come to terms with quantum jumps and in fact or himself said that if you think you've understood it then you haven't really thought about it enough so I'm going to take a deep breath and under 30 seconds try and explain to you one of the most complicated concepts in the whole of science but one that underpins the entire universe Bohr described the atom not as a solar system but as a multi-story building the ground floors where the nucleus lives were the electrons occupying the floors above mysterious laws mean the electrons can only live on the floors never in between and other mysterious laws mean that sometimes that can instantaneously jump from one film to another these are what we call quantum jumps now Bohr had absolutely no idea what these laws were but thinking like this allowed him to make a startling prediction when an electron jumps from a higher floor to a lower one it gives off light more significantly the color of the light depends on how big or small the quantum jump the electron makes so an electron jumping from the third floor to the second floor might give off red light when an electron jumping from the tenth floor to the second floor blue light to test his new theory Bohr used it to make a prediction could it explain the mysterious signature in the spectrum of hydrogen after months of calculating furiously who finally came up with the results and his prediction was surprisingly accurate for the first time ever it looked like the spectrum can be explained back in 1913 that was big news but Bohr's new idea rested on a single seriously controversial supposition why should the electrons in the atom behave as though they were in a multi-story building and why should they magically perform quantum jumps from one story to another there was no precedent for it anywhere else in science when one physicists claimed the jumps were nonsense Moore replied yes you're completely right but that doesn't prove the jumps don't happen only that you cannot visualize them but not being able to visualize things seem to go against the whole purpose of science all the scientists in particular felt that science was supposed to be about understanding the world not about making up arbitrary rules that seemed to fit the data conflict between the two generations of scientists was inevitable cause weird new Adam and his crazy quantum jumps were a shot across the bow silence and the old school reacted and leading the traditionalists was giant of the physics world Albert Einstein he hated all his ideas and he was going to fight them anything from a sexual assault on Nats [Music] borther is undeterred and as the 1920s gone the battery needs for one of the greatest conflicts in all science Woodlawn so far the debates about the new atomic physics had been polite from gentlemen now the two sides wheeled out their biggest guns two of the greatest names in physics they were two very true trusting characters on those dicho for the new revolutionary science was a buttoned-up uber competitive German called Verner Heisenberg for the Conservatives as a debonair byron esque Austrian called Owen Schrodinger [Music] [Applause] Oh in Schrodinger passionate and poetic a philosopher and a romantic he wrote books on the ancient Greeks on philosophy on religion he was influenced by Hinduism there's also a very flamboyant character cool suave sophisticated a dapper dresser and a big hit with the ladies [Music] [Applause] schrödinger's promiscuity was legendary he had a string of girlfriends throughout his married life some of them much younger than him in 1925 38 year-old Schrodinger stayed at the Alpine resort of yoson Switzerland for a secret liaison with an old girlfriend whose identity remains a mystery to this day but their passion proved to be the catalyst but Schrodinger's creative genius another physicist said of Schrodinger's week of sexually inspired physics he had two tasks that week satisfy a woman and solved the riddle of the atom fortunately he was up to both he took de Bru's idea of mysterious pilot waves guiding electrons around an atom one crucial step further he argued that the electron actually was a wave of energy vibrating so fast it looked like a cloud around the atom a cloud like wave of pure energy and what's more he came up with a powerful new equation which completely described this way and so described the whole atom in terms of traditional physics the equation he came up with we now call schrödinger's wave equation it's incredibly powerful what's unique about it is that it features a new quantity called the wave function which Schrodinger claimed completely describe the behavior on the subatomic world [Music] Schrodinger's equation and the picture of the Atome painted created during a sexually charged holiday in the Swiss Alps once again allowed scientists to visualize the atom in simple terms it's hard to overestimate the relief Schrodinger's idea brought to the traditional physics community strange though his picture of the Aten was at least it was a picture and scientists love pictures they allowed them to use their intuition but there was still a deep nagging problem one that the radicals felt Schrodinger just couldn't reconcile his new theory still couldn't account for balls strange instantaneous quantum jumps the time had come for the radicals to hit back [Applause] in the summer of the same year one of Niels Bohr's protegees Verner Heisenberg was travelling to an obscure island of the north coast of Germany he was fiercely competitive and took Schrodinger's ideas as a personal affront he felt strongly that the strangeness of the instant quantum jumps was actually the key to understanding the atom he thought the atom was so unique and unusual it shouldn't be compromised through a simple analogy like a wave or an orbit or even a multi-story building he believed it was time to give up any picture of the atom at all Verner Heisenberg while the true geniuses of the 20th century young athletic a great mountain climber an excellent pianist he was also an exceptional student at the age of just 20 who was well on his way to finishing his ph.d and being courted by the great universities across Europe now in the summer of 1925 he was suffering from a particularly bad bout of hay fever his face was swollen up almost beyond recognition he decided to escape alone here to this beautiful but isolated island of helgeland he walked along the beaches he swam he climbed the rock and he pondered ever since he'd encountered atomic physics Heisenberg felt in his bones that all human attempts to visualize the atom to model it with familiar images would always fail the atom he believed was too capricious too strange to ever be explained that simply so he decided to abandon all pictures of it and describe it using pure mathematics alone but as he pondered he realized that the atom didn't just defy visualization it even defied traditional mathematics it was while he was here on helgeland the Heisenberg had an incredible revelation he realized that in order to describe certain properties of atoms he had to use a strange new type of mathematics it seems that certain properties like where an electron is at a given time and how fast it's moving where multiplied together the order in which you multiply there matters let me try and explain if we multiply two numbers together it doesn't matter which or do we do it in so 3 times 4 is clearly the same as 4 times 3 but when it came to atoms Heisenberg realized that the order in which he multiplied quantities together gave a different answer this quickly led him to other discoveries and he was convinced that he'd cracked a code in the atom that he'd somehow found the hidden mathematics within he was so excited he was also very scared that night he climbed to the top of a rock and sat there waiting till dawn he called it his night of helgeland when he returned to his University in getting and he told his colleague Max Born about it and they then worked together intensely for several months developing a whole new theory of the atom a theory that today we call matrix mechanics [Music] matrix mechanics uses complex arrays of numbers rather like a spreadsheet by manipulating these arrays Heisenberg and his mentor the brilliant physicist max all could accurately predict atomic behavior but from Einstein and the traditionalists this was pure scientific heresy an atom can't actually be a matrix of numbers surely we made of atoms not numbers back in Copenhagen Bohr and Paulie were thrilled with matrix mechanics so what if we couldn't imagine the atom as a physical object they exalted in the purity of the mathematics and launched into vicious attacks against Schrodinger's vulgar sensual waves Heisenberg wrote the more I reflect on the physical portion of Schrodinger's equation the more disgusting I find it in fact it's just [ __ ] but Schrodinger was equally scathing of Heisenberg saying he was repelled by his methods and found his mathematics monstrous in Munich in 1926 their enmity began to reach boiling points Schrodinger was to give a lecture on his wave equation Heisenberg scraped together the money to travel down to Munich for the lecture to finally come face to face with his rival what was at stake was more than just Heisenberg's reputation he believed Schrodinger's simplistic approach wasn't just misguided but totally wrong and his intention was nothing less than to destroy Schrodinger's theory Schrodinger delivers his lecture on the new wave mechanics to a packed audience the standing-room-only he writes down his new wave equation to Schrodinger this describes a real physical picture of the atom with electrons as waves surrounding the atomic nucleus 24-year old Verna Heisenberg is in the audience it can hardly contain himself at the end of the lecture he stands up and delivers a monologue attacking Schrodinger's approach for Heisenberg it's impossible to ever have a picture of what the atom is really like the audience is on Schrodinger side they'd much prefer his simple physical interpretation to Heisenberg's abstract complicated mathematics Heisenberg is booed he's told to sit down and be quiet he leaves the lecture sad and depressed Heisenberg returned to Copenhagen with his confidence severely dented there at the Institute he and Bohr reached their darkest moment almost all of the scientific community was against them they felt isolated desperate their backs were against the wall despite this they stubbornly refused to give up their controversial theory this attic room was Heisenberg study back in 1926 Bohr would come up here night after night we're here in Heisenberg would argue about the meaning of the new quantum mechanics they would argue so passionately but on one occasion apparently Heisenberg was reduced to tears and then as Heisenberg stared out of his attic window in despair the part below an extraordinary thought occurred to him it struck him why an atom can't be visualized why can't be understood intuitively it's not just because it's tiny tricky and difficult is because it's inherently unknowable he realized that there was a fundamental limit to how much we can know about the subatomic world for instance if we know where an electron is at a particular moment in time then we cannot know how fast it's moving but if we knew its speed we wouldn't know his position this ambiguity isn't a shortcoming in the theory itself nor was it due to the clumsiness of the way we carry out our measurements but a fundamental truth about the way nature behaves at the subatomic scale it became known as Heisenberg's uncertainty principle and is probably the most profound incredible yet unsettling concepts in the whole of science [Music] what Heisenberg had uncovered through his abstract matrix mechanics was a deep and shocking truth about the atomic world atoms are willfully obscure we can never fully know an atoms position and speed simultaneously the atomic world just refuses to allow that to happen it was completely mind-boggling but once they accepted it Heisenberg and Bohr who found the boost of confidence to be even more bold they realized uncertainty forced them to put a paradox right at the very heart of the atom atoms are not just unimaginable they're self-contradictory they behave both like particles and waves and it gets weirder when you're not looking at an atom it behaved like a spread-out wave but when you look to see where it is it behaves like a particle this is insane first atoms couldn't be visualized at all now it seems they change completely in character depending on whether or not you're looking at them the uncertainty principle had changed everything it revealed a shocking contradiction at the heart of nature everything we see is made of atoms and yet atoms themselves are unknowable they can only be understood through mathematics for the first time for Bohr and Heisenberg everything about the atom fell into place by the autumn of 1927 full of confidence and smarting for a fight they knew they were finally ready to take on the Conservatives [Music] for this physics showdown they chose the Solvay conference in Brussels all the world's leading atomic physicists would attend if war and Heisenberg was successful then they would lead a total scientific revolution this is amazing I'm looking at original footage of the Solvay delegates coming out of these doors there's Bohr talking to Schrodinger and and this Heisenberg behind them and there's Paolo Li strange looking guy on there's Einstein coming down with a big smile on his face for the week of the conference all that the delegates could think and talk about was Bohr's quantum mechanics with uncertainty now a central plank it was a truly formidable theory and over the week the final showdown played out between Bohr and his archrival Albert Einstein Einstein hated quantum mechanics and every morning he'd come to war with an argument that he felt picked a hole in the new theory war would go away very disturbed and think very hard about it and by the end of the day he'd come back with a counter argument that dismissed Einstein's criticism and this happened day after day until by the end of the conference Bohr had brushed aside all of Einstein's criticisms and Bohr was regarded as having been victorious and with that his vision play-actor which became known as the Copenhagen interpretation was suddenly at the very heart of atomic physics at the end of the conference they all gather for the team photo never before or since have so many great names of physics being together in one place at the front the elder statesmen of physics Hendrik Lorentz flanked on either side by Madame Curie and Albert Einstein Einsteins looking rather glum because he's lost the argument Louis debris has also failed to convince the delegates of his views victory goes to Niels Bohr he's feeling very pleased with himself next to him one of the unsung heroes of quantum mechanics the German Max Born who developed so much of the mathematics and behind them the two young disciples of Bohr Heisenberg and Pauli Poly's looking rather smugly across at Schrodinger bit like the cat who's got the milk this was the moment in physics when it all changed the old guard was replaced by the new chance of probability became interwoven into the fabric of nature itself and we could no longer describe atoms in terms of simple pictures but only using pure abstract mathematics the Copenhagen view had been victorious although Einstein went to his grave never believed in quantum mechanics solve a 1927 was the turning point at which the rest of the science establishments came to embrace the Copenhagen interpretation and that interpretation is still accepted today all the physics that I use in my research certainly the quantum mechanics that I teach my students and that fills the textbooks on my shelves is based on ideas that were hammered out and crystallized here at the Solvay conference in October 1927 in a sense everything I know about the way the world around me is made up started here the quantum mechanical description of the atom is one of the crowning glories of human creativity over the last of 18 years it has been proven right time after time and it's Authority has never been in doubt it's a monumental scientific achievement between 1905 and 1927 science changed our view of the world it also changed our view of science itself as scientists probed the tiniest building blocks of matter they created the most successful and powerful theory ever quantum mechanics it allows us to describe what everything in the universe is made of how it interacts and how it all fits together but it comes at a huge price at its most fundamental level we have to accept that nature is ruled by chance and probability Heisenberg's uncertainty principle dictates that there are certain limits on the sorts of questions we can ask the atomic world and most crucially while we now know so much more about what an atom is and how it behaves we have to give up any possibility of imagining what it looks like our human nature has forced us to ask questions of everything we see around us in the world what we've discovered has been beyond our wildest imagination [Music]
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