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Chapter 9 – Skeletal Muscles 1. Connective Tissue Surrounding a Skeletal Muscle: • Epimysium: Surrounds the entire muscle. • Perimysium: Surrounds bundles of muscle fibers (fascicles). • Endomysium: Surrounds individual muscle fibers. 2. Histology and Function of Sarcomeres: • Histology: Sarcomeres are the structural and functional units of skeletal muscles, composed of repeating units between two Z-lines. • Function: They enable muscle contraction through the sliding filament mechanism. 3. Main Components: • Thin Filaments: Actin, tropomyosin, and troponin. • Thick Filaments: Myosin. 4. Function of Transverse Tubules and Sarcoplasmic Reticulum: • Transverse Tubules (T-tubules): Transmit action potentials deep into the muscle fiber. • Sarcoplasmic Reticulum: Stores and releases calcium ions for muscle contraction. 5. Motor Unit: A motor neuron and all the muscle fibers it innervates. 6. Neuromuscular Junction: The synapse where a motor neuron meets a muscle fiber, allowing for signal transmission. 7. Synapse: A junction between two neurons or a neuron and a muscle cell where communication occurs. 8. Actions of Acetylcholine (ACh): • Initiates muscle contraction by binding to receptors on the sarcolemma. • Degraded by: Acetylcholinesterase. 9. Neurotransmitter Released at Motor Axon Terminals: Acetylcholine. 10. Steps in Excitation-Contraction Coupling: • Action potential travels along sarcolemma. • Calcium is released from the sarcoplasmic reticulum. • Calcium binds to troponin, causing tropomyosin to move, exposing binding sites on actin. • Myosin heads form cross-bridges and initiate contraction. 11. Order of Muscle Fiber Contraction: • Action potential → Calcium release → Cross-bridge formation → Power stroke → ATP binding → Cross-bridge detachment. 12. Mechanism of Muscle Contraction: • Sliding filament theory: Actin and myosin filaments slide past each other. 13. Interaction of Actin, Myosin, and Calcium: • Calcium binds to troponin, shifting tropomyosin to expose myosin-binding sites on actin, enabling cross-bridge cycling. 14. Cross-Bridges: Myosin heads that bind to actin during contraction. 15. Contraction Types: • Isotonic: Muscle length changes. • Eccentric: Muscle lengthens under tension. • Isometric: Muscle tension without length change. • Concentric: Muscle shortens under tension. 16. Force of Muscle Contraction: • Controlled by motor unit recruitment. • Partial Tetany: Incomplete relaxation. • Fused Tetany: Sustained contraction without relaxation. 17. Bones and Muscles as Levers: • Fulcrum: Pivot point of the lever. 18. Synergist and Antagonist: • Synergist: Assists the primary mover. • Antagonist: Opposes the primary mover. 19. Muscle Atrophy: Wasting of muscle due to disuse or disease. 20. Myasthenia Gravis: Autoimmune disorder causing muscle weakness by targeting ACh receptors. 21. Linea Alba: A fibrous structure running down the midline of the abdomen. 22. Origin, Insertion, and Actions of Specific Muscles: (Let me know which specific ones you’d like to focus on.) Chapter 17 – Digestive System 1. Alimentary Canal: A continuous muscular tube extending from the mouth to the anus. 2. Functions of the Digestive System: • Ingestion, digestion, absorption, and elimination. 3. Breakdown and Absorption: • Carbohydrates: Begin in the mouth (amylase). • Proteins: Start in the stomach (pepsin). • Fats: Start in the small intestine (lipase, bile). 4. Layers of Alimentary Canal Walls: • Mucosa, submucosa, muscularis, serosa. 5. Accessory Organs: • Liver, pancreas, gallbladder. 6. Sympathetic vs. Parasympathetic Effects: • Sympathetic: Decreases digestion. • Parasympathetic: Enhances digestion. 7. Hormones: • Gastrin: Stimulates gastric juice secretion. • Cholecystokinin (CCK): Stimulates bile and pancreatic juice. • Secretin: Stimulates bicarbonate secretion. 8. Peristalsis vs. Segmentation: • Peristalsis: Wave-like contractions. • Segmentation: Mixing movements. 9. Epiglottis Function: Prevents food from entering the trachea. 10. Heartburn: Caused by stomach acid reflux into the esophagus. 11. Stomach Parts: Fundus, body, pylorus. 12. Secretions: • Parietal Cells: Hydrochloric acid, intrinsic factor. • Chief Cells: Pepsinogen. 13. Digestive Enzymes and Substances: • Amylase: Breaks down starch. • Pepsin: Digests proteins. • Trypsin: Protein digestion. • Lipase: Fat digestion. • Bile Salts: Emulsify fats. 14. Liver, Gallbladder, Pancreas Functions: • Liver: Produces bile. • Gallbladder: Stores bile. • Pancreas: Produces enzymes and bicarbonate. 15. Anatomy of Bile Ducts: • Common hepatic, cystic, and pancreatic ducts form the common bile duct. 16. Functions of Large Intestine: • Absorption of water, vitamin production, and feces formation. 17. Defecation Reflex: Triggered by rectal wall distension. Chapter 18 – Nutrition 1. Excess Glucose Storage: As glycogen in the liver and muscles. 2. Tissue Requiring Glucose: Nervous tissue (brain). 3. Triglyceride Components: Glycerol and three fatty acids. 4. Essential Amino Acids: Cannot be synthesized by the body

10.2 Thick and Thin Filaments

POLICE PHOTOGRAPHY A. DEFINITION OF TERMS: 1. Photography = Derived from the Greek word “Phos” or “Photos” which means “light” and “Grapho” means “Writing” or “Graphia” meaning “to Draw”. Sir John F. W. Herschel coined the word photography when he first wrote a letter to Henry Fox Talbot. = Is the art and science of reproducing image by means of light through some sensitized material with the aid of a camera, Lens and its accessories and the chemical process required in order to produced a photograph. 2. Forensic = Derived from the Latin word “Forum” which means “a market place” where people gathered for public discussion. = When used in conjunction with other science it connotes a relationship to the administration of justice. It is sometimes used interchangeably with the word legal. 3. Police Photography = Is the application of the principles of photography is relation to the police work and in the administration of justice. 4. Photograph = Is the mechanical and chemical result of Photography. Picture and photograph are not the same for a picture is a generic term is refers to all kinds of formed image while a photograph is an image that can only be a product of photography. B. USES OF PHOTOGRAPHY 1. Personal Identification = Personal Identification is considered to be the first application of photography is police work. Alphonse Bertillion was the first police who utilized photography in police work as a supplementary identification in his Anthropometry system. 2. For Communication = Photograph is considered to be one of the most universal methods of communication considering that no other language can be known universally than photograph. 3. For Record Purposes = Considered to be the utmost used of photography in police work. Different Views in photographing a. General View = taking an over-all view of the scene of the crime. It shows direction and location of the crime scene. b. Medium View = Is the taking of the photograph of the scene of the crime by dividing it into section. This view will best view the nature of the crime. c. Close-up View = Is the taking of individual photograph of the evidence at the scene of the crime. It is design to show the details of the crime. d. Extreme Close-up View = Commonly designed in laboratory photographing using some magnification such as Photomacrography and photomicrography. 4. For Preservation = Crime scene and other physical evidence requires photograph for preservation purposes. Crime scene cannot be retain as is for a long period of time but through photograph the initial condition of the scene of the crime can be preserved properly. 5. For Discovering and Proving = Photography can extend human vision in discovering and proving things such as: a. The use of Magnification Photomicrography = Taking a magnified photograph of small object through attaching a camera to the ocular of a compound microscope so as to show a minute details of the physical evidence. Photomacrogaphy = Taking a magnified (enlarged) photograph of small object by attaching an extended tube lens (macro lens) to the camera. Microphotography = is the process of reducing into a small strips of film a scenario. It is first used in filmmaking. Macrophotography = used synonymously with photomacrogaphy. Telephotography = Is the process of taking photograph of a far object with the aid of a long focus and Telephoto lens. b. Used of Artificial Light such as X-ray, Ultra-violet and Infra-red rays to show something which may not be visible with the aid of human eye alone. 6. For Court Exhibits = Almost all evidence presented in court before formally be accepted requires that they satisfy the basic requirements for admissibility which is relevancy and competency. A question of relevancy is usually proved by proving the origin of the evidence and its relation to the case and this is usually supplemented by photograph of the evidence giving reference as to where it came from. Evidence presented in court once accepted became known as Exhibit. Either Exhibit 1,2,3 etc. for the defense or Exhibit A, B, C etc for the prosecution. 7. Crime Prevention = with the used of video camera (hidden camera) and other advanced photographic equipment crimes are being detected more easily and even to the extent of preventing them from initially occurring. 8. Police Training = Modern facilities are now being used as instructional material not only in police training as well as in other agencies. 9. Reproducing and Copying = With the use of photography any number of reproduction of the evidence can be made those giving unlimited opportunity for its examination and even allow other experts or person to examine the specimen without compromising the original. C. ESSENTIALS OF PHOTOGRAPHY 1. Light = is an electromagnetic energy that travels in a form of a wave with the speed of 186, 000 miles per second. 2. Camera = a light tight box designed to block unwanted or unnecessary light from reaching the sensitized material. 3. Lens = is the light gathering mechanism of the camera that collect the reflected light coming from the object to form the image. 4. Sensitized material = composed of a highly sensitized chemical compound which is capable of being transformed into an image through the action of light and with some chemical processes. ( Film and Photo Paper). 5. Chemical Process = is the process necessary for reducing silver halides into a form so as a latent image and a positive image be made resulting to what we called Photograph. D. THEORIES OF LIGHT 1. The WAVE Theory (Huygens) = It is the theory that was transcribed from the motion of the water that if we observe a piece of log floating in the ocean and with the force of the air would naturally will make the log move up and down. 2. Corpuscular theory (Newton) = this later opposed the wave theory stating that light has its effect by the motion of very small particles such as electrons. 3. Modified Wave theory (Maxwell and hertz) = Based on electromagnetics. All these theories are still considered to be of little lacking that law enforcement need not to be very focus on this but rather go along with the accepted conclusion that light is a form of energy, which is electromagnetic in form. E. LIGHT: ITS NATURE, CHARACTERISTICS, SOURCES AND CLASSIFICATION Light is defined as an electromagnetic energy with the speed of 186,00 miles per second. Its wave travel is said to be characterized in certain extent based on velocity, wavelength and frequency of the number of vibration of the wave per second. Light wavelength is the distance measured between two (2) successive crest or through of wave and it is expressed in either Millimicron (nanometer) or Angstrom. Millimicron is the units of light wavelength which is equivalent to one-millionth part of a millimeter which the Angstrom is relatively smaller for it has an equivalent measurement of ten (10) millionth part of a millimeter. Once light hits a certain medium, its action can be characterized as either: Reflected, Transmitted or Absorbed (RAT). Reflected once the light hits a mirror and it bounce back. Transmitted when the light hits a transparent glass which would allow the light to pass through its medium and Absorbed when the light hits a dark colored object and prevents it from either bouncing or passing through. Isaac Newton in 1666 proved that the light which men see as white light is actually a mixture of all colors of the spectrum. This is produced when we allow light to hit a glass prism (Sharp Edge of the Glass). A rainbow array will then be shown with colors red, orange, yellow, green, blue and violet colors (from top to bottom). The visible light is also said of have a wavelength of between 400-700 millimicron or nanometer. 1. Types of Light Lights can largely be classified into visible and invisible light. a. Visible Light = Is the type of light that produces different sensation when reach the human eye. It is the type of light, which is capable of exciting the retina of the human eye. b. Invisible Light = lights in which their wavelength are either too short or too long to excite the retina of the human eye i.e. X-ray, Ultrat-violet and Infra-red lights. 2. Photographic Rays a. X-ray =Light with the wavelength between .01 to 30 millimicrons. It is produced by passing an electric current through a special type of vacuum tube. It was incidentally discovered by Conrad Welhelm Roentgen. This type of light works in the principle of shadow photography. b. Ultra-violet ray (Before the violet) = Radiation having a wavelength of 30 to 400 nanometers designed to photograph fingerprints in multi colored background, documents that are altered, decipherment of erase writing and developing invisible writing. It is commercially known as “black Light”. c. Visible Light = It refers to the type of radiation having a wavelength of 400 to 700 millimicrons designed for ordinary photographing purposes. d. Infra-red (Beyond the Red) = Considered as the photographic rays with the longest wavelength ranging from 700 to 1000 millimicrons. It is designed to take photograph of over-written documents, obliterated writing, and charred documents or for black out photography. It is sometimes referred to as heat rays). 3. Light Source A. Natural Light= are those light which come to existence without the intervention of man e.i. Sunlight, moonlight and starlight. 1. Bright Sunlight = object in an open space casts a deep and uniform shadow and the object appears glossy. 2. Hazy Sunlight = object in an open space casts a transparent or bluish shadow. This is due to thin clouds that cover the sun. 3. Dull Sunlight = object in an open space cast no shadow due to thick clouds covering the sun. Daylight may still be classified as: open space bright sunlight, under shade bright sunlight, hazy sunlight, cloudy sunlight and cloudy dull sunlight. These conditions and their colors affect the appearance of the object being photograph. Factors such as atmospheric vapor, atmospheric dust and quality of the reflected light coming and not coming from the source should likewise be considered. B. Artificial Light = otherwise known as man-made light e.g. fluorescent bulb, incandescent bulb and photoflood lamp. 1. Continuous radiation Photoflood lamp= is likewise known as Reflectorized light or Spot light. It is a light with a reflector at the back which focus the light to the object the common wattages of this lamp is 500 watts. Flourescent Lamp = are tube lamps in which the walls are coated with fluorescent powders with both ends is mounted with a holder that serves as the reflector. This is commonly used by everybody more than it is used in photographing. Incandescent bulb = are bulb with a wire filament connecting two wires which sustain the electrical charge that produces the light. Everybody likewise commonly uses this although it is more expensive in terms of electrical consumptions. Infra-red Lamp Ultra-violet Lamp 2. Short Duration type Flash bulb = are chemical lamps, as it generate lights by the rapid combination of metal in oxygen. The bulb can be used only once as the bulb is busted when fired electrically. There are thin filaments inside the bulb with two electrical contacts. When the current flows through the filament, it becomes incandescent and ignites the explosive primer that ignites the aluminum foil that burns, giving flash of tense light. Electronic Flash = produces light by an instantaneous electrical in charges between two electrodes in a gas filled glass bulbs. The electrical energy for the discharge is kept in capacitor or condenser. It usually ranges from 1/300 second and 1/5000 second, and because of this, subject in fast motion can be arrested or stopped in the photographs. 4. SENSITIZED MATERIAL = It refers to the film and photographic paper that basically composed of emulsion containing Silver Halides suspended in gelatin and coated on a transparent or reflective support. Parts of the Sensitized Material 1. Emulsion = is that part of the film or photographic paper which contains the silver grains which is the one sensitive to light. In a colored film this emulsion surface can be composed of three layers (Blue, Green and Red) with filters intervening. 2. Anti Halation Backing = is the one designed to hold back the light and prevents halation. 3. Base = Support the emulsion I. Types of Film A. According to Use 1. Black and White Film = usually represented by a prefix or a suffix “Pan” or “Ortho” and generally used in black and white photography. Examples are Ortholith film, Tri X-Pan and Pan X-plus. 2. Colored Film = can be divided into two: the Negative type and the reversal type of colored film. The former is usually having names ending in color while the word chrome represents the latter. e.g. Blue sensitive film, Ultra-violet film, Infra-red film, Orthochromatic film and Panchromatic film. B. According to Spectral Sensitivity Spectral sensitivity = is the responsiveness of the film emulsion to the different wavelength of the light course. 1. Blue – Sensitive film = sensitive to U.V. light and Blue Color. 2. Orthochromatic Film = Sensitive to U.V. Light up to the green. ( popular in the marker as KODALITH FILM) 3. Panchromatic film = Sensitive to U.V. Light up to red (sensitive to all colors of the visible light) 3.1. Process Panchromatic film = permit short exposures under average lighting condition and has the advantage of the grain structure. 3.2. Grain Panchromatic film 3.3. High Speed Panchromatic film designed originally for photographing object under adverse lighting condition. 4. Infra-red Film = Sensitive to all colors and to infra-red light. FILM SPEED (Emulsion Speed) This refers to the degree of sensitivity of the film to light. 1. ASA (American Standards Association) = this is expressed in arithmetic value system. The bigger the number the more sensitive the film is. ASA 10, 20 , 30 , 40,50, 100, 200, 400, 800, 1000 2. DIN ( Deutche Industre Normen) = expressed in Logarithmic value system. Used in the same principle as the ASA. Din 12, 15, 18, 21, 24, 27, 30, 33 etc. 3. ISO (International Standard Organization) expressed as combination of ASA and DIN rating. II. Photographic Paper It is that sensitized material that will record the visible image in the final development and become the photograph. Types of Photographic Papers A. According to Emulsion Used (Silver halides content) 1. Silver Chloride paper = used for contact printing, the size of the positive print is the same as the size of the negative used. Sensitivity to light is low and give blue-black tones when properly developed. 2. Silver Bromide paper = used projection, printing and enlarging process. This is one of the most ideal photo paper used for police photography. Will give a black tone when properly developed. 3. Silver Chlorobromide paper = used both for projection and contact printing. Slow emulsion. 4. Variable contract paper = combines the contrast range in one paper it uses a special chlorobromide emulsion that produces varying contrast responses upon exposure to different colors of light. B. According to Physical Characteristics b.1. Weight 1. Light weight = designed for high flexibility and when paper thickness is not of consideration. Intended for purposes, which involves folding. 2. Single Weight = papers used for small prints or which are need to be mounted on solid and fine details necessary in the production. Used in ordinary photographic purposes. 3. Double weight = generally used for large prints because they stand up under rough treatment. b.2. Surface Texture a. Glossy paper =designed for fine details and brillant image formation. b. Semi-mate paper = obscure the fine details c. Rough papers = used for large prints or where breath rather than detail is necessary. b.3. Color a. White = better used in police photography. b. Cream = preferred for pictorial effect, portraits, landscape or when warmth effect is desired. c. Buff papers = prepare for tone prints C. According to Contrast (grade) 1. Velox No. 0 = used for printing extremely contrast negative or extremely exposed film. 2. Velox No. 1 = used for high contrast negative (over exposed film) 3. Velox No. 2 = used for normal exposed film 4. Velox No. 3 = used for negative with weak contrast (under exposed) 5. Velox No. 4 = used to provide sufficient contrast to compensate for very thin or weak negatives. It is useful imprinting which high contrast is desired. 6. Velox No. 5 = for flat negative that are unprintable. 5. CAMERA Is a light tight box with light gathering device and a means of blocking unwanted or unnecessary light from reaching the sensitized material. Basically, camera can produce image with its four-(4) basic parts such as light tight box, lens, and shutter, Holder of sensitized material. Essential Parts of a Camera 1. Light Tight Box – a box designed to keep light out and serve as a frame to hold other parts. 2. Lens – designed to collect or to focus the reflected light from an object to form an image on the film. 3. Shutter – designed to control the time during which the light reaches the film 4. Holder of the sensitized material – located at the opposite side of the lens designed to hold firmly the sensitized material to prevent the formation of the multiple or blurred image 5. View finder – designed to determine the field of view of the camera or the extent of the coverage of the given lens OTHER PARTS OF A CAMERA A. Viewing System Is that part of the camera which provides the means of showing to the photographer the entire scene coverage that can be recorded in the sensitized material. B. Film Advancer (film advance lever or knob) =designed to transfer the exposed film to the other side or to the take up spool and the unexposed film will be the opposite side of the lens for another exposure. C. Shutter speed = is that part of the camera which regulates the time exposure of the film thus, affecting the amount of light reaching the sensitized material. It is usually expressed in a fraction of a second. 1/1 1/2 1/4 1/8 1/15 1/30 1/60 1/125 1/250 1/500 etc. The speed number in the left is always two times powerful in terms of light gathering than that of the right number Using a fast shutter speed the photographer can stop or “freeze” the action of a person provided that necessary adjustment on the lens opening be made in order to maintain normal exposure. D. Lens Aperture = the ratio between the diameter of the whole lens in relation to the focal length of the lens. It is the light gathering power of the lens. Otherwise known as lens opening or relative aperture and it is expressed in F-number. f 2.8 f-4 f-5.6 f-8 f-11 f-16 The lower the f-number, the bigger the lens opening and the bigger the lens opening the greater the volume of air that will passed through the lends and reach the sensitized material. If the objective of a photographer is obtain the widest possible coverage of the lens in which objects are all sharp, It will be advisable to used a smaller lens opening. E. Focusing = is that mechanism of a camera designed to control the degree of sharpness of the object to be photograph. It is usually obtained by estimating the distance from the camera and that of the object that will make a sharp or clear image. Types of focusing device: 1. Range finder (Either coincidence or split image type) Coincidence otherwise known as superimposed image focusing. In this type of focusing a single object will appeared double once the object is not in focus, but moving the focusing adjustment this double image will coincide or superimposed to form a single object. Split Image focusing on the other hand will show an image in split or two parts once the object in not in focus once the two parts of the image has been united then the object is already focused 2. Ground Glass This is observed from the viewing system of the camera, once the object is not in focused the object will be viewed to be blurred and will turn sharp and clear once adjusted. 3. Scale Bed Estimating the distance of the object and adjusting the camera control based on his estimation do this. TYPES OF THE CAMERA 1. View Finder Type – it is considered as the smallest and the simplest type of camera 2. Single Lens Reflex Camera – it is a type of camera best suited for police work due to its interchangeability of the lens 3. Twin Lens Reflex Camera – A type of camera with dual lens, one for focusing and the other for forming the image. 4. View or Press type – is considered the biggest and expensive type of camera, used for movie making 5. LENS = It is the image-forming device of the lens that actually has a greater effect on the quality of the image to be formed. = a medium or system which converge or diverge light rays passing through it to form an image. = Can be a glass or transparent material, which permit light to pass through and change the direction of light. Daniel Barbaro = first to introduce the use of lens in the camera. CLASSIFICATION OF LENSES 1. According to the type of image to be produced a. Positive or Convex Lens (Converging Lens) Characterized by the fact that it is thicker at the center and thinner at the side which is capable of bending the light together and forms the image inversely. b. Negative or Concave Lens (diverging Lens) Characterized by the fact that it is thinner at the center and thicker at the side and forms the virtual image on the same side of the lens. 2. According to Degree of Corrections a. Meniscus Lens = lens that has no correction. b. Rapid Rectilinear Lens – lens corrected of distortion c. Anastigmat Lens – correcting astigmatism d. Achromatic Lens – correcting chromatic aberration e. Apochromatic Lens – correcting both astigmatism and chromatic aberration INHERRRENT LENS DEFECTS 1. Spherical Aberration= Inability of the lens to focus light passing the side of the lens producing an image that is sharp in the center and blurred at the side. 2. Coma = (Also known as lateral aberration) = Inability of the lens to focus light that travels straight or lateral, thus making it blurred while the light reaching the lens oblique is the one the is transmitted sharp. 3. Curvature of Field = the relation of the images of the different point are incorrect with respect to one another. 4. Distortion = Is a defect in shape not in sharpness. It can either be Pincushion distortion (curving inward) or Barrel (curving outward). 5. Chromatic Aberration = Inability of the lens to focus light of varying wavelength. The lens refracts rays of short wavelength more strongly than those of longer wavelength and therefore bringing blue rays to a shorter focus than the red. 6. Astigmatism= is a form of lens defects in which the horizontal and vertical axis are not equally magnified. Inability of the lens to focus both horizontal and vertical lines. 7. Chromatic Difference of Magnification 8. Flares = condition of the lens producing multiple images. LENS CHARACTERISTICS 1. Focal Length – is the distance measured from the optical center of the lens is set to focus at infinite position. As according to focal lenses may be classified as: a. Wide Angle or Short Focus = with focal length not longer than the diagonal half of the negative. Useful in taking photograph at short distance with wider area coverage. b. Normal or Medium Focus = with focal length approximately equal but not longer than twice the diagonal half of the negative. c. Long or Telephoto Lens = with focal length longer than twice the diagonal half of the negative. Best used in long distance photographing but with narrow area coverage. d. ZOOM lens = lens with variable focal length or that which can be adjusted continuously by the movement of one or more elements in the lens system. 2. Relative Aperture – the light gathering power of the lens expressed in F-number a. Depth of Field – is the distance measured from the nearest to the farthest object in apparent sharp focus when the lens b. Hyperfocal distance = Is the nearest distance at which when a lens is focused with a given particular diaphragm opening will gives the maximum depth of field. 3. Focusing = is the setting of the proper distance in order to form a sharp image. The one that controls the degree of sharpness of the object. 6. CHEMICAL PROCESS The process of making the latent image visible and permanent. a. Development (Use of either D-76, Dektol or Universal Solution) = Is the process necessary for reducing the silver halides to form the image. Elon, Hydroquenone = used as main developing agents b. Stop bath = normally composed of water with little amount of dilute acetic acid that serves as a means to prevent contamination between the developer and the acid fixer. c. Fixation = Is the process by which all unexposed silver halides are dissolved or removed from the emulsion surface and making the image more permanent. Sodium Thiosulfate (hypo) is the main fixing agent that dissolves unexposed silver halides. Other chemicals used: Acetic Acid and Boric acid = serves as neutralizer Sodium Sulfate = serves as the preservative Potassium Bromide = restrainer or hardener Sodium bicarbonate and borax powder = serves as accelerator Dodging = is the process of eliminating unwanted portion of the negative during enlarging. Cropping = is the process of omitting an object during the process of enlarging and printing. Vignetting = is the gradual fading of the image towards the side through skillful adjustment on the dodging board. Dye toning = is the process designed in changing the color tone of the photograph. Burning-In = refers to additional exposure on a desired portion of the negative used for purposes of making a balance exposure.

Chapter 10: Muscle Tissue

fdjksl afdjs klejfsieofwjnervous system the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems three critical features of the nervous system They receive input from the surrounding world. They process the info from the surroundings. They initiate responses to the internal and external environments, when necessary. neuron a nerve cell; the basic building block of the nervous system dendrites Branchlike parts of a neuron that are specialized to receive information. cell body Largest part of a typical neuron; contains the nucleus and much of the cytoplasm axon the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands glial cell cells in the nervous system that support, nourish, and protect neurons nerves bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs how many neurons die everyday? 9,000 When neurons die can they be replaced? no what can kill neurons? alcohol intake, inhaling gas fumes neurons are what kind of cell eukaryotic what does the cell body contain nucleus, mitochondria, endoplasmic reticulum, and so on What does a dendrite do? receives information what does the axon do? carries impulses away from the cell body what does the cell body do? process information sciatic nerve nerve extending from the base of the spine down the thigh, lower leg, and foot How many more glial cells are there than neurons? 9x Do glial cells divide? yes glial cells act as a barrier for harmful things entering the brain blood brain barrier Blood vessels (capillaries) that selectively let certain substances enter the brain tissue and keep other substances out how is the blood brain barrier broken down hypertension, radiation, some infectious organisms sensory neurons neurons that carry incoming information from the sensory receptors to the brain and spinal cord. stimulations like temp, touch, taste, smell, light or sound motor neurons neurons that carry outgoing information from the brain and spinal cord to the muscles and glands Interneurons neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs. peripheral nervous system network of sensory cells modified to receive info from the environment and motor pathways that transmit signals to effectors, the muscles and glands capable of responding to that stimulus sensory pathway nerves coming from the sensory organs to the CNS consisting of afferent neurons motor pathways In the peripheral nervous system, common routes by which motor nerve impulses are transmitted. somatic nervous system the division of the peripheral nervous system that controls the body's skeletal muscles (voluntary) autonomic nervous system the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms. (involuntary) sensory neurons alert the brain of a stimulus motor neurons help the brain to execute a response reflex signal that skips the brain, and goes to stimulate the motor neuron. direct sensory response autonomic nervous system helps us with homeostasis sympathetic nervous system the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations parasympathetic nervous system the division of the autonomic nervous system that calms the body, conserving its energy dendrites recieve signals from external stimuli two ways dendrites receive stimuli through motor neurons and interneurons connecting with other neurons or directly from external stimulus resting potential of neuron its stable, negative charge when the cell is inactive action potential of neuron a very brief shift in a neuron's electrical charge that travels along an axon resting potential is produced as proteins within the neurons plasma membrane pump sodium ions out of the cell and potassium ions into the cell what ion goes into the cell potassium what ion goes out of the cell sodium how does the pumping of ions affect the charge of the cell? more positive on the outside more negative on the inside greater positive charge out of the cell makes the cell polarized when stimulated dendrites briefly open ion channels made of proteins which allow charged ions down the concentration gradient concentration gradient A difference in the concentration of a substance across a distance. when ion channels open the negative charge inside the cell is temporarily changed either decreasing or increasing changes in the cells electrical charge converge from the dendrites to the cell body when charges converge that is called action potential terminal buttons Small knobs at the end of axons that secrete chemicals called neurotransmitters axon terminals (terminal buttons) doe what i response to action potential release contents of vesicles, small sacks of chemicals inside the axon terminal into the space between cells which can influence nearby cells myelin sheath A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next. as the action potential moves down the axon ion channels allow positively charged ions to rush in changing the charge to positive. other ion channels allow positively charged ions to rush out what restores the action potential ion channels letting the influx of positively charged ions to rush put Where are ion channels concentrated in the gaps in the myelin sheath fatty myelin is what color white fatty myelin shows up as white when tightly packed together regions of the brain with many cell bodies and dendrites appear what color gray multiple sclerosis myelin sheath destruction. disruptions in nerve impulse conduction little myelin causes the neurons to lose its ability to conduct electrical impulses which makes it harder for the brain to send signals to muscles synapse the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron at a synapse and neurons interacts with another cell What happens at a synapse? When a nerve impulse reaches the synapse at the end of a neuron, it cannot pass directly to the next one. Instead, it triggers the neuron to release a chemical neurotransmitter. The neurotransmitter drifts across the gap between the two neurons. sacs called vesicles release neurotransmitters into the synaptic cleft synaptic cleft The narrow gap that separates the presynaptic neuron from the postsynaptic cell. what happens when the action al potential reaches the axon terminal? little sacks called vesicles merge with axon cell membrane axon cell membrane presynaptic membrane the vesicles open and release chemicals called neurotransmitters neurotransmitters send a signal to the cell receiving the signal after sending a signal to a cell the neurotransmitters diffuse away and binds to nearby receptor sites after neurotransmitters diffuse the gates open in the post synaptic cell membrane and the signal enters the post synaptic cell after the signal enters a new neurotransmitter is released from the post synaptic cell receptors and is recycled or broken down what are neurotransmitters broken down by enzymes found in the synaptic cleft when a postsynaptic cell is a muscle cell it contracts when a postsynaptic cell is a gland it secretes how do neurotransmitters affect the neuron by causing it to fire on its own action potential or receives the likelihood of it firing on its own action potential what a neurotransmitter does to a neuron is decided by receptor the ability for neurons to not fire helps with filtering overwhelming sensory info such as a concert Acetylcholine A neurotransmitter that enables learning and memory and also triggers muscle contraction Acetylcholine is released by motor neurons at the point where they synapse with muscle cells Botulinum toxin an acetylcholine antagonist; prevents release by terminal buttons. most toxic substance known what does botox do blocks release of acetylcholine so less contractions in muscles =less wrinkles glutamine involved with learning and memory, more sensitive to glutamine, better memory and learning dopamine influences movement, learning, attention, and emotion. loss of is responsible for parkinson's. chief of happiness serotonin Affects mood, hunger, sleep, and arousal who makes serotonin more? men cocaine a powerful and addictive stimulant, derived from the coca plant, producing temporarily increased alertness and euphoria. tricks pleasure center in brain and binds with presynaptic membrane where dopamine is usually reabsorbed from the synaptic cleft. blocks reuptake sites dopamine remains in cleft repeatedly stimulating it prozac and zoloft block serotonin from being reabsorbed and recycled by presynaptic cells which prolongs it affect Selective Serotonin Reuptake Inhibitors (SSRIs) a group of second-generation antidepressant drugs that increase serotonin activity specifically, without affecting other neurotransmitters morphine and heroin mimic endorphins and bind to receptor sites. in high doses gives endorphins rush which causes euphoria. slows down respiratory rate and can be fatal nicotine mimics acetylcholine by binding to the same receptors and release adrenaline and other stimulating chemicals. rapid surges the rapid depletions of these chemicals make smokers want another cigarette drugs become addictive because the body's think that there is more natural amounts of usual neurotransmitters. reduces sensitivity to drugs, needing more to have the same reaction DRD4 gene that encodes a certain class of dopamine receptor. It can be mutated for those seeking sensation, altering the mesolimbic pathway and the way sensations are rewarded caffeine a mild stimulant found in coffee, tea, and several other plant-based substances cellular waste products takes form of a variety of molecules such as adenosine adenosine when binds with receptor reduces the likelihood of a neuron initiating an action potential as more adenosine binds with more receptors we feel tired when we sleep cellular waste products are reabsorbed and recycled effects of alcohol slowed down reactions slurs speech by blocking receptors for glutamate, provides buzz by blocking dopamine reuptake, blocks pain by stimulating the release of endorphins, increases feeling of happiness by modifying the efficiency of serotonin receptors muscles generate force through contraction skeletal muscle is attached to bones by connective tissue and is controlled by individual neurons attached to each muscle fiber cardiac muscles causes the heart to pump blood blood through the body smooth muscle, involuntary, surrounds blood vessels and many internal organs which help to move blood, move food through digestive system myofibrils cylindrical organelle within muscle cells that can contract; contains repeating units, called sarcomeres in which the contraction takes place Sarcomere the fundamental unit of muscle contraction , made of actin myosin actin protein of muscle tissue; makes up the thin filaments myosin protein of muscle tissue, making up the thick filaments muscle fiber contraction Results from a sliding movement where the actin and myosin filaments merge using ATP. Globular portions of the myosin filaments can form cross-bridges with actin filaments. Reaction between actin and myosin filaments generates the force of contraction. First step of sarcomere contraction detach, link between myosin and a parallel action filament is broken as a molecule of ATP bonds to myosin Second step of sarcomere contraction reach, as the atp breaks down, energy released alters the shape of the myosin into a higher energy shape and myosin now reaches farther down the actin filament Third step of Sarcomere contraction reattach, the myosin reattaches to the actin filament at this new location Fourth step of Sarcomere contraction pull back, the myosin then snaps back to its original shape, pulling the actin filament as it does so and shorting the fiber relaxed sarcomere Actin & Myosin myofilaments lie side by side contracted sarcomere the Z lines are close together duration between contraction and relaxation is called twitch fast twitch muscle fibers that react quickly and fatigue quickly slow twitch type of muscle that contracts slowly and is fatigue resistant Oxytocin peptide hormone, produced in neurons within the hypothalamus and released by the posterior pituitary, influences trust in others, increases the social attachments, directs the ejection of breast milk, and contractions in the uterus during childbirth synthesis site of oxytocin hypothalamus target tissues of oxytocin uterus and mammary glands effect of oxytocin Effects uterus - uterine contractions during labor, direct myometrium, other effects are on limbic system in both men and women increased by touch - reflects on bonding and trust hormones chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues two systems for carrying out communication nervous and endocrine endocrine system the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream endocrine cells produce regulatory hormones target cells cells that have receptors for a particular hormone endocrine glands Glands of the endocrine system that release hormones into the bloodstream endocrine gland examples pituitary, thyroid, parathyroid, adrenal, pineal hormones help regulate homeostasis pheromones Chemical signals released by an animal that communicate information and affect the behavior of other animals of the same species. such as sexual reproduction and territory marking step one of how a hormone affect a certain cell signal is sent by a hormone being released from a gland step two of how a hormone affects a certain cell signal is received, although the hormone has no effect on most tissues it comes in contact with, cells with the right receptor in their cytoplasm or on their plasma membrane receives the signal step three of how a hormone affects a certain cell cell responds, hormone binds to receptor, causes response in target cell, can be change in gene expression in nucleus, can cause cell to start or stop producing a certain protein, alter rate of producing protein amines hormones adrenaline, hormones that are synthesized from single amino acids polypeptide hormones insulin and glucagon, chains of amino acids steroid hormones estrogen and testosterone, lipids lipid Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen. most amines and polypeptide hormones are — while lipids are not water soluble amines and polypeptide hormones — pass through memebrane cannot lipids —pass through membranes can amines and polypeptide hormones bind to receptors embedded within the cell membrane which can influence inside the cell steroids hormones bind to receptors within the cytoplasm or nucleus of the cell, always passes into nucleus once a steroid is in the nucleus it binds to DNA, influencing gene expression paracrine receptors target cell receptors for a specific hormone can be nearby hormones secreted by glands in one part of the body are able to regulate cell function in another part of the body Prostaglandins Modified fatty acids that are produced by a wide range of cells. dilation or construction of blood vessels and affecting tissue inflammation what does asprin do Inhibits prostaglandins, decreases inflammation, and slows transmission of pain to site of injury Hypothalamus underside of brain, functions as liaison between the nervous and endocrine systems and it receives input from neurons throughout the brain and rest of body. sends out appropriate hormones to regular nearly every aspect of the organisms physiology, including body temp, hunger. thirst, and water balance pituitary gland The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands. posterior pituitary gland also known as the neurohypophysis; it is made up of nervous tissue/neurons and stores and secretes 2 hormones made by the hypothalamus (oxytocin and ADH); it is controlled by action potentials from the hypothalamus antidiuretic hormone (ADH) influences the absorption of water by kidney tubules anterior pituitary produced many hormones such as TSH, LH, FSH, prolactin, ACTH Thyroid Stimulating Hormone (TSH) causes thyroid to produce thyroxine, important in cellular respiration Follicle-stimulating hormone (FSH) stimulates development of follicles in ovaries and sperm maturation Lutenizing hormone (LH) triggers ovulation and stimulates testosterone production, works with FSH prolactin stimulates mammary glands to produce milk Adrenocorticotropic hormone (ACTH) Stimulates adrenal glands to produce cortisol and other stress related hormones Corticotropin-releasing hormone (CRH) Promotes secretion of adrenocorticotropic hormone (ACTH) growth hormone several effects, stimulating liver to release chemicals that spur growth of bones, cartilage, and other tissues excessive production of growth hormone during childhood can cause extreme growth called gigantism increased exposure to growth hormone in adulthood results in hands, face, feet growing unusually absence of growth hormone dwarfism how is pituitary dwarfism treated if caught early? shots of human growth hormone pineal gland secretes melatonin regulates sleep cycles thyroid gland releases thyroxine, influences the rate and efficient of cellular metabolism, regulates calcium levels in blood parathyroid glands regulate calcium levels in blood adrenal glands release adrenaline and cortisol (prepares body for action), regulate organisms response to stress. sit right above kidneys. pancreas releases insulin and glucagon, maintains blood glucose levels wishing a narrow range gonads release the sex steroids, including testosterone, estrogen, and progesterone, responsible for numerous physical, behavioral, and emotional features, including much sexual behavior, development, and growth Under active thyroid fatigue and weight gain overactive thyroid jitteriness, rapid heartbeat, weight loss, irritability when iodine intake is low, the thyroid is unable to produce thyroxine which causes thyroid to swell Calcitonin Lowers blood calcium levels insulin A hormone produced by the pancreas or taken as a medication by many diabetics negative feedback A primary mechanism of homeostasis, whereby a change in a physiological variable that is being monitored triggers a response that counteracts the initial fluctuation. positive feedback Feedback that tends to magnify a process or increase its output. endocrine disrupters Chemicals that disrupt normal hormone functions Polychlorinated biphenyls (PCBs) A group of industrial compounds used to manufacture plastics and insulate electrical transformers, and responsible for many environmental problems. Phthalates found in cosmetics, deodorants, and many plastics used for food packaging, children's toys, and medical devices. Cause kidney & liver damage, cancer, and low sperm counts. Bisphenol A (BPA) a substance widely used in plastics and to line food and drink cans, which has raised health concerns because it is an estrogen mimic endocrine disrupters effect on mammals reproductive harm endocrine disrupters effect on fish reproductive functioning endocrine disrupters effect on invertebrates defective shells, masculinization of female genitalia, reducing fertility oxytocin posterior pituitary, uterus, breast, brain, reduce stress, more trusting "love hormone" antidiuretic hormone (ADH) posterior pituitary, kidneys, water retention in kidneys Thyroid Stimulating Hormone (TSH) anterior pituitary, thyroid, stimulates production of thyroxine, important in cellular respiration Follicle-stimulating hormone (FSH) anterior pituitary, ovaries, testes, stimulates ovary development and sperm maturation prolactin anterior pituitary, mammary glands, milk production growth hormone anterior pituitary, liver and other organs, stimulates release of chemicals that spur growth of bones, cartilage, and other tissues cortisol and adrenaline adrenal glands, smooth, cardiac, skeletal muscle, blood vessels, cell throughout body, imitates response to stress, regulates response to long term stress melatonin pineal gland, brain, regulate sleep cycle thyroxine thyroid, cells throughout body, influenced metabolic spew and efficiency calcitonin and parathyroid hormone thyroid, bones, causes bones to pick up excess calcium in blood insulin pancreas, liver, adipose tissue, skeletal muscle, take up glucose in blood which reduces its level glucagon pancreas, liver, adipose tissue, concert stored glycogen into glucose estrogen, testosterone, progesterone gonads, cells uterus, breasts, balls, puberty, pregnancy, sperm production, egg production heritable sensory autonomic neuropathy condition in which afflicted individual cannot feel pain sensory neurons affected by skin and joints affected by syphilis Interneurons are affected by parkinsons motor neurons are affected by polio Oligodendrocytes Type of glial cell in the CNS that wrap axons in a myelin sheath. Microglia Act as phagocytes, eating damaged cells and bacteria, act as the brains immune system astrocyte release gliotransmitters by expcytosis to send signals to neighboring neuron connectomes Map of the network of connections between neurons in the human brain resting potential -70 mV action potential +30 mV (depolarized) Channelopathies diseases and disorders that are the result of ion channel dysfunction Tetrodotoxin -Poisoning can result from ingestion of poorly prepared puffer fish (exotic sushi) -Highly potent toxin that binds fast voltage-gated Na+ channels in cardiac and nerve tissue, preventing depolarization - blocks action potential without changing resting potential (same mechanism as Lidocaine) -Causes nausea, diarrhea, paresthesias, weakness, dizziness, loss of reflexes. -Treatment is primarily supportive. epilepsy potassium channel mutations, muscle weakness the synapse excitatory neurotransmitters chemicals released from the terminal buttons of a neuron that excite the next neuron into firing inhibitory neurotransmitters chemicals released from the terminal buttons of a neuron that inhibit the next neuron from firing GABA An inhibitory neurotransmitter in the brain. caffeine — glutamine and — GABA activity increases, decreases Alcohol — GABA activity and — Glutamate activity increases, decreases functions of muscle generate movement, force, heat, homeostasis 2 mutates copies of them upstairs gene causes excess muscle build up muscle is composed of bundles of muscle fibers bundles of muscle fibers are composed of muscle fibers muscle fibers are composed of myofibrils myofibrils are composed of actin and myosin actin and myosin are composed of sarcomere slow fiber muscle is dark mest fast fiber muscle is light meat motor unit A motor neuron and all of the muscle fibers it innervates rigor mortis stiffness after death caused by lack of ATP, muscle remains in a state of contraction acromegaly abnormal enlargement of the extremities during adulthood when exposed to excess growth hormone Addison Disease low levels of cortisol, autoimmune disease, depression, dizziness, low blood glucose, low blood pressure chronic stress excess cortisol, high blood glucose, obesityfdwkqfejifijeoiefowojk