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57 Cards in this Set
- Front
- Back
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Polymer
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A polymer is a large molecule composed of many repeated subunits, known as monomers. Because of their broad range of properties, both synthetic and natural polymers play an essential role in everyday life
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Natural polymers
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Natural polymers have been on earth, way before us humans came. Natural polymers include, RNA, and DNA, that are so important in genes and life processes.
Natural polymers occur in nature, and are extracted by humans for everyday use, examples of natural polymers may be: silk, wool, cellulose etc |
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Synthetic polymers
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Synthetic polymers are man made, usually by scientists or engineers, examples of synthetic polymers are: Nylon, Polyrthene, Polyester, neopone
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Enzymes in digestion
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- Enzymes are biological catalysts that increase the rate of reaction
- Digestive enzymes are secreted into the lumen of the gut - Digestive enzyme increase the rate of reaction of the hydrolysis of insoluble food molecules to soluble end products - Digestive enzymes increase the rate of reaction at body temperature |
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Amylase
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Amylase is an enzyme that catalyses the breakdown of starch into sugars. Amylase is present in human saliva, where it begins the chemical process of digestion.
- Foods that contain much starch but little sugar, such as rice and potato, taste slightly sweet as they are chewed because amylase turns some of their starch into sugar in the mouth. T |
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Protease
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A protease (also termed peptidase or proteinase) is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain forming the protein.
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Amylase, protease, lipase
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Source the Pancreas
Optimal pH 7.5-7.8 Substrate is starch (amylose) End product is the disaccharide maltose Action: hydrolysis of 1-4 glycosidic bonds |
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Function of stomach
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The stomach stores the food from a meal and begins protein digestion.
(a) Lumen of the stomach which stores the food from a meal (b) Gastric pits from which mucus , enzymes and acid are secreted (c) Mucus secreting cells. Mucus protects the surface of the stomach from auto-digestion (d) Parietal cells that produce HCL which kills microorganism that enter the digestive system (food & tracheal mucus). This also converts inactive pepsinogen to active pepsin (e) Chief cells: produces pepsinogen a protease enzyme |
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Function of small intenstine
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In the small intestine digestion is completed.
The products of digestion are absorbed into the blood stream. (a) Villus which increase the surface area for absorption of the products of digestion (b) Microvilli border of the epithelial cell increases the surface are for absorption. (c) Lacteals are connect to the lymphatic system for the transport of lipids. (d) In the wall of the small intestine are the blood vessels to transport absorbed products to the general circulation, There are also the muscle to maintain peristalsis |
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Function of large intenstine
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The colon is responsible for the reabsorption of water from the gut.
(a) The lumen of the colon - The colon is the last part of the digestive system (b) The mucus producing goblet cells (b) Muscular walls to maintain peristalsis |
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Absorption
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The soluble products are first taken up by various mechanisms into the epithelial cells that line the gut.
These epithelial cells then load the various absorbed molecules into the blood stream. |
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Assimilation
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The soluble products of digestion are then transported to the various tissues by the circulatory system.
The cells of the tissues then absorb the molecules for use within this tissues |
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Diastole
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- The heart muscle is relaxed this is called diastole.
- There is no pressure in the heart chambers. - Blood tries to flow back into the heart but closes the semi-lunar valves. |
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Myogenic
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Myogenic contraction refers to a contraction initiated by the myocyte cell itself instead of an outside occurrence or stimulus such as nerve innervation. Most often observed in smaller resistance arteries, this 'basal' tone may be useful in the regulation of organ blood flow and peripheral resistance, as it positions a vessel in a preconstricted state that allows other factors to induce additional constriction or dilation to increase or decrease blood flow.
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Functions of arteries and veins
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Arteries carry blood away form the heart under high pressure.
- Veins return blood to the heart under lower pressure. - Capillaries are the site of exchange of blood with tissue fluid and cells. |
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Plasma
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- Plasma is largely water and makes up about 55% of the total blood volume.
- This is the main transporting part of blood and takes advantage of the solvent properties of water. |
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Erythrocytes (Phagocytes)
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- Erythrocytes are the red blood cells.
- Phagocytes eat/consume/engulf waste material |
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Leucocytes (Lymphocyte)
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- Leucocytes are the white blood cells
- Lymphocyte is a smaller white blood cell that serves to fight infection along with immune responses in the body. |
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Pathogen
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- A pathogen is an organism that can cause disease.
- Pathogens include bacteria, viruses, protista, fungi and other parasitic multicellular organisms. |
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Antibiotics
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- Antibiotics block specific metabolic pathways found in bacteria, but not in eukaryotic cells.
- Bactericidal or fungicidal antibiotics kill microbes. - Others are antibiotics are static (bacteriostatic, fungistatic, etc.), which means they stop further growth, but don't kill existing cells. - Both are useful medically, because if the growth of an infective pathogen is stopped, the body's immune system will be able to kill it. - Viruses do not have metabolic pathways like bacteria and therefore antibiotics do not work on viruses. - Viruses can only be treated by their specific anti-microbial agent and antibiotics should never be prescribed for viral infections (such as flu). |
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Skin
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- outer laywer: epidermis 20-30 cell thick, toughened by keratin
- dermis, 20-40 times thicker, main skin layer contains sensory receptor cells, blood capillaries and hairs. |
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Phagocytic leucocytes
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The role of phagocytic white blood cells is, responsible for finding, immersing and assimilating microorganisms. They also eat up foreign substances, abnormal cells, cellular debris and waste products. They are basically the body's garbage collectors and they are two types of phagocytic and these include neutrophils and macrophages.
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Phagocytosis
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The phagosome fuses with lysosomes which contain containing lysozymes. These enzymes killing and digesting the microbes. The process called phagocytosis
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Antigen
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Antigen is often used to describe something that has infected the body. However it is more accurate to describe them as follows:
- An antigen is a large molecule (protein, glycoprotein, lipoprotein or polysaccharide) on the outer surface of a cell. - All living cells have these antigens as part of their cell membrane or cell wall. - The capsid proteins of viruses and even individual protein molecules can also be classed as antigens. - Their purpose is for cell communication, and cells from different individuals have different antigens, while all the cells of the same individual have the same antigens. - Antigens are genetically controlled, so close relative have more similar antigens than unrelated individuals. - Blood groups are an example of antigens on red blood cells, but all cells have them. - The link with infection is that when a pathogen or toxin enters the body it this that the immune system reacts against. |
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Antibodies
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Antibodies are proteins secreted from lymphocytes that destroy pathogen and antigen infections
B-cells make antibodies. An antibody (also called an immunoglobulin) is a protein molecule that can bind specifically to an antigen. Antibodies all have a similar structure composed of 4 polypeptide chains (2 heavy chains and 2 light chains) joined together by strong disulphide bonds to form a Y-shaped structure. The stem of the Y is called the constant region because in all immunoglobulin's it has the same amino acid sequence, and therefore same structure. The ends of the arms of the Y are called the variable regions of the molecule because different immunoglobulin molecules have different amino acid structure and therefore different structures. These variable regions are where the antigens bind to form a highly specific antigen-antibody complex, much like an enzyme-substrate complex. |
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Antibody production
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There are many different lymphocytes.
(b) The antigen infects and is presented to the lymphocytes (c) The lymphocyte with a surface epitope complementary to the antigen is selected. (d) The Lymphocyte clones to produce many plasma cells. This occurs in the lymph nodes. (e) The clone of plasma cells (f) The gene for the antibody is expressed and secreted into the plasma and tissue fluid. (g) The antibody circulated in body fluids destroying the infectious antigen |
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Ventilation:
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The flow of air in and out of the alveoli is called ventilation and has two stages: inspiration (or inhalation) and expiration (or exhalation).
Lungs are not muscular and cannot ventilate themselves, but instead the whole thorax moves and changes size, due to the action of two sets of muscles: the intercostal muscles and the diaphragm. |
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Gas exchange
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This is the diffusion of gases (oxygen and carbon dioxide)
There are two sites for gas exchange (a)Alveoli: Oxygen diffuses into the blood from the alveoli and carbon dioxide diffuses from the blood into the alveoli (b)Tissues: Oxygen diffuses from blood into the cells and carbon dioxide diffuses from cells to the blood |
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Cell respiration
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Aerobic respiration uses oxygen in the mitochondria and produces carbon dioxide
Anaerobic respiration does not use oxygen but still produces carbon dioxide |
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Ventilation system
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(a) Trachea
(b) Cartilage ring support (c) Bronchi (plural) Bronchus (single) (d) Lung (e) Heart (f) Sternum (g) Rib cage (h) Bronchioles (j) Alveoli (k) Diaphragm |
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Neuron
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A neuron (also known as a neurone or nerve cell) is an electrically excitable cell that processes and transmits information through electrical and chemical signals.
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Types of neurons
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Sensory neurons have long axons and transmit nerve impulses from sensory receptors all over the body to the central nervous system.
Motor neurons also have long axons and transmit nerve impulses from the central nervous system to effectors (muscles and glands) all over the body. Interneurones (also called connector neurons or relay neurons) are usually much smaller cells, with many interconnections. |
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Resting potential
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Resting potential is the negative charge registered when the nerve is at rest and not conducting a nerve impulse.
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Action potentia
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Action potential is the positive electrochemical charge generated at the nerve impulse. Normally this is seen as the 'marker' of the nerve impulse position.
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Depolarisation
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Depolarisation is a change from the negative resting potential to the positive action potential.
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Re-polarisation
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Re-polarisation is the change in the electrical potential from the positive action potential back to the negative resting potential.
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Synaptic transmission
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- The junction between two neurons is called a synapse.
- An action potential cannot cross the synaptic cleft between neurons, and instead the nerve impulse is carried by chemicals called neurotransmitters. - These chemicals are made by the cell that is - sending the impulse (the pre-synaptic neuron) and stored in synaptic vesicles at the end of the axon. - The cell that is receiving the nerve impulse (the post-synaptic neuron) has chemical-gated ion channels in its membrane, called neuroreceptors. - These have specific binding sites for the neurotransmitters |
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Homeostasis
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Homeostasis ("hómoios", "similar" stásis, "standing still") is the property of a system that regulates its internal environment and tends to maintain a stable, relatively constant condition of properties such as temperature or pH. It can be either an open or closed system. In simple terms, it is a process in which the body's internal environment is kept stable.
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Hypothalamus
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The hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions of the hypothalamus is to link the nervous system to the endocrine system via the pituitary gland (hypophysis).
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The endocrine system
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The endocrine system is the system of glands, each of which secretes different types of hormones directly into the bloodstream (some of which are transported along nerve tracts[citation needed]) to maintain homeostasis.
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Vasoconstriction
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Vasoconstriction: is a cold adaptation narrowing of arterioles that reduces blood flow to the surface of the skin is coupled with a dilation of the horizontal shunt vessels. This prevents heat loss from blood near the skin surface and retains heat in the body core for essential organs.
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Vasodilation
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Vasodilation: is an adaptation to warm conditions in which arterioles dilate sending more blood closer to the skin surface from where heat can be radiated to the surrounding environment. The horizontal shunt vessels are constricted sending most blood closer to the skin surface. Additionally sweat (mainly water) is released onto the surface of the skin where it enters the vapour phase when warmed by the heat carried by blood. Therefore the vapour of sweat carried away heat energy from blood.
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Osmosis
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content of a tissue is determined by the concentration of the surrounding tissues.
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Respiration
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Some tissues are entirely dependent on blood sugar as a respiratory substrate being unable to either store glucose of metabolise fat.
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Endocrine glands
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are glands that secrete their products through the basal lamina into the blood stream and lack a duct system.
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Exocrine glands
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Secrete their products through a duct or directly onto the apical surface, the glands in this group can be divided into three groups:
1. Apocrine glands — a portion of the secreting cell's body is lost during secretion. Apocrine gland is often used to refer to the apocrine sweat glands, however it is thought that apocrine sweat glands may not be true apocrine glands as they may not use the apocrine method of secretion. 2. Holocrine glands — the entire cell disintegrates to secrete its substances (e.g., sebaceous glands) 3. Merocrine glands — cells secrete their substances by exocytosis (e.g., mucous and serous glands). Also called "eccrine". |
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The pancreas
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The pancreas is a glandular organ in the digestive system and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, somatostatin, and pancreatic polypeptide, and a digestive organ, secreting pancreatic juice containing digestive enzymes that assist the absorption of nutrients and the digestion in the small intestine. These enzymes help to further break down the carbohydrates, proteins, and lipids in the chyme.
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Type I diabetes
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(early or juvenile onset):
Auto-immune disease in which the beta-cells pancreatic are destroyed. Unable to produce insulin. Responds well to regular injection of insulin probably manufactured as the genetically engineered humulin. |
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Type II diabetes
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Adult onset
Reduced sensitivity of the liver cells to insulin. Reduced number of receptors on the liver cell membrane. |
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Similarities between type I and II diabetes
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a build of glucose in the blood stream and it will then subsequently appear in urine.(test with a Clinistic )
High concentrations of blood glucose (hyperglycaemia) results in the movement of water from cells by osmosis. This extra fluid in the blood results in larger quantities of urine production. A lack of glucose in cells means that fats then proteins have to be metabolised in respiration. Particularly the breakdown of protein for energy creates organ damage. |
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Female reproductive system
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Male reproductive system
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FSH (follicle stimulating hormone) and LH (luteinizing hormone)
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- The cycle is controlled by hormones from both the brain (FSH and LH) and the ovary(oestrogen and progesterone).
- The natural cycle repeats until there is either a pregnancy or the woman reaches menopause and the end of the reproductive phase of her life. F- SH and LH are two hormone that are active at significant phases of human development including primary and secondary sexual characteristics. They are both significant hormones in the primary sex determination. Following puberty human become fertile and in females this is manifest as the menstrual cycle. - progesterone gives negative feedback on these |
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Testosterone
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1. Week 7 of embryonic development, testosterone initiates the development of male genitalia.
2. Around mid teens, testosterone initiates the development of secondary sexual characteristics increase in muscle mass increase in the length of the long bones (height) increase in the length of the vocal cords (voice deepens) spermatogenesis growth of the penis and testis 3. Post puberty testosterone maintains the production of sperm cells and the male sex drive. |
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In Vitro fertilization (IVF)
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Digestive system
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Process of cloning
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