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The Human Body Structure & Function of Major Systems of the Human Body

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Presentation on theme: "The Human Body Structure & Function of Major Systems of the Human Body"— Presentation transcript:

1 The Human Body Structure & Function of Major Systems of the Human Body
Zarin Rahman, AP Bio 2013

2 The Digestive System Just Guts!

3 Function Turns food into energy needed to survive and packages residue for waste disposal. Mechanical and chemical breakdown of food. Food enters mouth (mastication) › travels down esophagus (deglutition) › enters the stomach and intestine (digestion) › waste is eliminated (defecation).

4 Major and Accessory Organs
Major organs of digestion: Mouth Esophagus Stomach Small intestine Large intestine Rectum Anus Accessory organs of digestion: Gallbladder, pancreas, and liver.

5 Part One: Mastication When food enters the mouth, digestion starts by mastication, a form of mechanical digestion, and the contact of saliva.  Saliva, secreted by salivary glands, contains salivary amylase, an enzyme that digests starch in food. Food forms into bolus.

6 Part Two: Deglutition Bolus is pushed into esophagus through the pharynx. Using smooth muscle contractions known as peristalsis, the esophagus delivers food to stomach. At junction of the esophagus/stomach, ring-like muscle (lower esophageal sphincter) closes passage between. As food approaches, the sphincter relaxes and allows the food to pass through to the stomach.

7 Part Three: Digestion Stomach is a small, 'J'-shaped pouch with walls made of thick, distensible muscles. Food enters the stomach through the cardiac orifice, further broken apart and thoroughly mixed with gastric acid, pepsin and other digestive enzymes to break down proteins.  Enzymes require optimum pH to create acidic conditions in which they work best.

8 Part Three: Digestion Pepsin in the stomach denatures proteins, reducing polypeptide bonds and disrupting salt bridges, which causes a loss of 2˚, 3˚, or 4˚ protein structure. Parietal cells of stomach also secrete a glycoprotein called intrinsic factor, which enables the absorption of vitamin B-12.  Mucus neck cells of stomach secrete mucus, which along with gastric juice lubricates and protects mucosal epithelium from excoriation by highly concentrated hydrochloric acid.

9 Part Three: Digestion Small molecules (i.e. alcohol) are absorbed, passing through membrane of stomach and entering circulatory system directly. Food in the stomach is in semi-liquid form, which upon completion is known as chyme. (approx. 2-4 hours after mastication & deglutition)

10 Part Three: Digestion Peristaltic contractions begin, help break down food and move it onward. Chyme reaches the opening to the duodenum (pylorus) and retropulsion exerts additional force and further grinds down food into smaller particles. Gastric emptying occurs, releasing of food from stomach into the duodenum. After being processed in the stomach, food is passed to small intestine via  pyloric sphincter. Majority of digestion and absorption occurs after the milky chyme enters the duodenum.

11 Part Three: Digestion Chyme mixed with 3 other liquids:
Bile: emulsifies fats to allow absorption, neutralizes chyme, used to excrete waste products such as bilin and bile acids. Bile is produced by the liver and then stored in the gallbladder where it will be released to the small intestine via the bile duct.

12 Part Three: Digestion Pancreatic juice made by the pancreas, which secretes enzymes such as pancreatic amylase, pancreatic lipase, and trypsinogen (inactive form of protease). Helps digest proteins, carbohydrates, and fats.

13 Part Three: Digestion Intestinal juice secreted by the intestinal glands in the small intestine. It contains enzymes such as enteropeptidase, erepsin (which further digests polypeptides into amino acids, completing protein digestion), trypsin, chymotrypsin, maltase, lactase and sucrase (all three of which process only sugars). Small, finger-like structures (villi) and their epithelial cells covered with numerous microvilli improve absorption of nutrients by increasing surface area of intestine, enhancing speed of absorption.  Blood containing absorbed nutrients is carried from small intestine via the hepatic portal vein to the liver for filtering, removal of toxins, and nutrient processing.

14 Part Three: Digestion Whatever material is left goes into the large intestine. Function: storage and fermentation of indigestible matter. Four parts: ascending colon, descending colon, transverse colon, and sigmoid colon.

15 Part Three: Digestion Less vigorous in absorption activity.
Digestion is retained to allow fermentation due to the action of bacteria, which breaks down some of the substances that remain after processing in the small intestine; some of the breakdown products are absorbed. In humans, these include most complex saccharides. Large intestine absorbs water from the chyme and stores feces.

16 Part Four: Defecation Waste product is stored in the rectum for a certain period and then waste is eliminated from the body through contraction and relaxation through the anus. The exit of this waste material is regulated by the anal sphincter.

17 A Closer Look: Breakdown & Absorption
Proteins Occurs in the stomach and duodenum in which 3 main enzymes, pepsin secreted by the stomach and trypsin and chymotrypsin secreted by the pancreas, break down food proteins into polypeptides that are then broken down by various exopeptidases and dipeptidases into amino acids. 

18 A Closer Look: Breakdown & Absorption
Fats Can begin in the mouth where lingual lipase breaks down some short chain lipids into diglycerides. Presence of fat in small intestine produces hormones that stimulate the release of pancreatic lipase from the pancreas and bile from the liver for breakdown of fats into fatty acids. Complete digestion of one molecule of fat (a triglyceride) results in 3 fatty acid molecules and one glycerol molecule.

19 A Closer Look: Breakdown & Absorption
Carbohydrates Bonds between glucose molecules broken by salivary and pancreatic amylase, resulting in smaller chains of glucose. Results in simple sugars glucose and maltose that can be absorbed by the small intestine. Lactase breaks down the disaccharide lactose to its component parts, glucose and galactose. Glucose and galactose can be absorbed by the small intestine. Sucrase breaks down the disaccharide sucrose. Sucrose digestion yields the sugars fructose and glucose which are readily absorbed by the small intestine.

20 A Closer Look: Breakdown & Absorption
DNA & RNA DNA and RNA are broken down into mononucleotides by the nucleases deoxyribonuclease and ribonuclease (DNase and RNase) from the pancreas.

21 Chemical vs. Mechanical Digestion
Catabolism Glandular structures, dispersed throughout the body, are involved in breaking food into simple molecules that can be absorbed. Use of enzymes. Mastication Food is crushed and liquefied by the teeth, tongue Break down of food into usable energy molecules. Peristalsis Waves of involuntary muscle contraction of the stomach and small intestine. 

22 Disorders of the Digestive System
Celiac Disease  an autoimmune disorder of the small intestine that occurs in genetically predisposed people of all ages from middle infancy onward caused by a reaction to gliadin, a prolamin (gluten protein) found in wheat, and similar proteins found in the crops of the tribe Triticeae (which includes other common grains such as barley and rye)

23 Disorders of the Digestive System
Celiac Disease: Signs & Symptoms Pale, loose and greasy stool (steatorrhoea). Weight loss or failure to gain weight (in young children).  Intermittent diarrhea Abdominal pain Bloating Irritability or depression, anemia, stomach upset, joint pain, muscle cramps, skin rash, south sores, dental and bone disorders (such as osteoporosis), tingling in the legs and feet (neuropathy) may also occur.

24 Disorders of the Digestive System
Celiac Disease : Prevalence Affects between 1 in 1,750 in the world, and 1 in 105 people in the United States. Almost all people with celiac disease have either the variant HLA-DQ2 allele or (less commonly) the HLA- DQ8 allele. However, about 20–30% of people without celiac disease have also inherited either of these alleles. This suggests additional factors are needed for celiac disease to develop.

25 Disorders of the Digestive System
Celiac Disease: Treatment Diet- To manage the disease and prevent complications, it's crucial to avoid all foods that contain gluten, including: barley, bulgur, durum, farina, graham flour, rye, semolina, spelt (a form of wheat), triticale, wheat Supplements- Take vitamin and mineral supplements recommended by doctors or dietitian to help correct deficiencies: Calcium, folate, iron, vitamin B-12, vitamin, vitamin K

26 Disorders of the Digestive System
Crohn’s Disease Type of inflammatory bowel disease that may affect any part of the gastrointestinal tract from mouth to anus, causing a wide variety of symptoms. Causes inflammation of the lining of your digestive tract.

27 Disorders of the Digestive System
Crohn’s Disease: Signs & Symptoms Diarrhea Abdominal pain and cramping Blood in stool Ulcers Reduced appetite and weight loss Other symptoms include: fever, fatigue, arthritis, eye inflammation, mouth sores, skin disorders, inflammation of the liver or bile ducts, delayed growth or sexual development (in children)

28 Disorders of the Digestive System
Crohn’s Disease: Prevalence Affects between 400,000 and 600,000 people in North America. Prevalence estimates for Northern Europe have ranged from 27–48 per 100,000. Crohn's disease tends to present initially in the teens and twenties, with another peak incidence in the fifties to seventies, although the disease can occur at any age.

29 Disorders of the Digestive System
Crohn’s Disease: Treatment There is currently no cure for Crohn's disease, and there is no one treatment that works for everyone. Treatment for Crohn's disease usually involves drug therapy or, in certain cases, surgery. Anti-inflammatory drugs: Sulfasalazine, Mesalamine, Corticosteroids. Immune system suppressors: Azathioprine, Mercaptopurine, Infliximab, Adalimumab, Certolizumab pegol, Methotrexate, Cyclosporine, Natalizumab. Antibiotics: Metronidazole, Ciprofloxacin. Other drugs: anti-diarrheals, laxatives, pain relievers, vitamin B-12 shots, supplements.

30 Digestive System: A Summary

31 Why was the endocrine student so upset? He failed a teste.
The Endocrine System Why was the endocrine student so upset? He failed a teste.

32 Function System of glands, each of which secretes different types of hormones directly into the bloodstream to maintain homeostasis. An information signal system like the nervous system. Hormones regulate various human functions, including metabolism, growth and development, tissue function, sleep, and  mood.

33 Homeostasis & the Endocrine System
What is homeostasis? The human body’s ability to maintain balance or return systems to functioning within a normal range. Interactions within the body facilitate compensatory changes supportive of physical and psychological functioning.  The liver, the kidneys, and the brain (hypothalamus, the autonomic nervous system and the endocrine system) help maintain homeostasis.

34 Homeostasis & the Endocrine System
Role of endocrine system: synthesizing and releasing hormones, chemical messengers. major areas of control and integration include responses to stress and injury, growth and development, absorption of nutrients, energy metabolism, water and electrolyte balance, reproduction, birth, and lactation. many endocrine glands are linked to neural control centers by homeostatic feedback mechanisms. The two types of feedback mechanisms are negative feedback and positive feedback. most are negative feedback mechanisms

35 Negative Feedback Mechanisms
Negative feedback mechanisms act like a thermostat in the home. As the temperature rises (deviation from the ideal normal value), the thermostat detects the change and triggers the air-conditioning to turn on and cool the house. Once the temperature reaches its thermostat setting (ideal normal value), the air conditioning turns off.

36 Negative Feedback Mechanisms
Blood calcium level. parathyroid glands secrete parathyroid hormone, which regulates the blood calcium   if calcium decreases, parathyroid glands sense the decrease and secrete more parathyroid hormone. Parathyroid hormone stimulates calcium release from bones and increases the calcium uptake into the bloodstream from the collecting tubules in the kidneys. conversely, if blood calcium increases too much, the parathyroid glands reduce parathyroid hormone production. both responses are examples of negative feedback because in both cases the effects are negative (opposite) to the stimulus.

37 Negative Feedback Mechanisms
Blood calcium level.

38 Insulin and Cell Signaling
Insulin is the major hormone controlling critical energy functions such as glucose and lipid metabolism. insulin activates the insulin receptor tyrosine kinase (IR), which phosphorylates and recruits different substrate adaptors.  activated Akt induces glycogen synthesis, and cell survival.  insulin stimulates glucose uptake in muscle and adipocytes via translocation of GLUT4 vesicles to the plasma membrane.

39 The Endocrine System

40 Insulin and Cell Signaling
Complex insulin cell signaling involving all intermediates.

41 Insulin and Cell Signaling
Low glucose vs. Elevated glucose level and the action of insulin.

42 Type I Diabetes vs. Type II Diabetes
Body can’t use its insulin. Body make no insulin. Can be due to genetic factors. Usually in children and teens. Also due to obesity. Feeling tired or ill, frequent urination, tiredness, unusual thirst, weight loss, blurred vision, frequent infections and slow wound healing, asymptomatic. Usually in adults and the elderly 5% -10% of total cases. 90%- 95%-of total cases.

43 Disorders of the Endocrine System
Acromegaly  syndrome that results when the anterior pituitary gland produces excess growth hormone (GH) after epiphyseal plate closure at puberty. most commonly affects adults in middle age, and can result in severe disfigurement, complicating conditions, and premature death if unchecked. Because of its pathogenesis and slow progression, the disease is hard to diagnose in the early stages and is frequently missed for years until changes in external features, especially of the face, become noticeable. acromegaly is often associated with gigantism.

44 Disorders of the Endocrine System
Acromegly: Signs and Symptoms Enlarged hands and feet Coarsened, enlarged facial features Coarse, oily, thickened skin Excessive sweating and body odor Small outgrowths of skin tissue (skin tags) Fatigue and muscle weakness A deepened, husky voice due to enlarged vocal cords and sinuses Severe snoring due to obstruction of the upper airway Impaired vision Headaches Enlarged tongue Pain and limited joint mobility Menstrual cycle irregularities in women Erectile dysfunction in men Enlarged liver, heart, kidneys, spleen and other organs Increased chest size (barrel chest)

45 Disorders of the Endocrine System

46 Disorders of the Endocrine System
Acromegaly: Prevalence approximately 4,676 cases per million population, and the incidence is new cases per million per year.

47 Disorders of the Endocrine System
Acromegaly: Treatment The goals of treatment are to reduce GH production to normal levels, to relieve the pressure that the growing pituitary tumor exerts on the surrounding brain areas, to preserve normal pituitary function, and to reverse or ameliorate the symptoms of acromegaly. Currently, treatment options include surgical removal of the tumor, drug therapy, and radiation therapy of the pituitary. André René Roussimoff, aka Andre the Giant, famous actor and wrestler, suffered from acromegaly. He was 7 feet 4 inches and 520 pounds when he died from heart compliations (due to acromegaly) at age 46.

48 Disorders of the Endocrine System
Acromegaly: Treatment Drugs Somatostatin analogues The primary current medical treatment of acromegaly is to use somatostatin analogues – octreotide (Sandostatin) or lanreotide (Somatuline). These somatostatin analogues are synthetic forms of a brain hormone, somatostatin, which stops GH production. Dopamine agonists For those unresponsive to somatostatin analogues, treatment using one of the dopamine agonists, Bromocriptine (Parlodel) or Cabergoline.

49 Disorders of the Endocrine System
Acromegaly: Treatment Surgery Surgery is a rapid and effective treatment, of which there are two alternative methods. The first method, a procedure known as Endonasal Transphenoidal surgery, involves the surgeon reaching the pituitary through an incision in the nasal cavity wall. The wall is reached by passing through the nostrils with microsurgical instruments. The second method is Transsphenoidal surgery during which an incision is made into the gum beneath the upper lip.

50 Disorders of the Endocrine System
Acromegaly: Treatment Radiation Therapy Radiation therapy has been used both as a primary treatment and combined with surgery or drugs. It is usually reserved for patients who have tumor remaining after surgery. These patients often also receive medication to lower GH levels. his treatment lowers GH levels by about 50 percent over 2 to 5 years.

51 Looking for jokes about the excretory system? Well urine luck.

52 Function A passive biological system that removes excess, unnecessary materials from an organism, so as to help maintain homeostasis within the organism and prevent damage to the body.  Responsible for the elimination of the waste products of metabolism as well as other liquid and gaseous wastes, as urine.

53 Organs of the Excretory System
Kidney  essential in the urinary system; serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and regulation of blood pressure (via maintaining salt and water balance).   natural filter of the blood, and remove wastes which are diverted to the urinary bladder excrete wastes such as urea and ammonium, and they are also responsible for the reabsorption of water, glucose, and amino acids. produce hormones including calcitriol, erythropoietin, and the enzyme renin.

54 Organs of the Excretory System
Ureters tubes made of smooth muscle fibers that propel urine from the kidneys to the urinary bladder. usually 25–30 cm (10–12 in) long and ~3-4 mm in diameter  arise from the renal pelvis on the medial aspect of each kidney before descending towards the bladder on the front of the psoas major muscle.

55 Organs of the Excretory System
Bladder organ that collects urine excreted by the kidneys before disposal by urination. hollow muscular, and distensible (or elastic) organ

56 Organs of the Excretory System
Urethra tube that connects the urinary bladder to the genitals for the removal of fluids from the body external urethral sphincter is a striated muscle that allows voluntary control over urination

57 The Kidney

58 Nitrogenous Wastes  Ammonia is a toxic by-product of the metabolic removal of nitrogen from proteins and nucleic acids. Dilute solutions of ammonia Most aquatic animals get rid of ammonia by excreting it in very dilute solutions with the water. Urea Terrestrial animal would have to urinate copiously; toxic, could only be transported in the animal and excreted in a very dilute solution. Mammals and most 1 amphibians excrete urea; handled in much concentrated form. Uric acid Land snails, insects, birds, and some reptiles excrete uric acid. Thousands of times less soluble in water than either ammonia or urea, uric acid can be excreted as a precipitate after nearly all the water has been reabsorbed from the urine. In birds and reptiles, the pastelike urine is excreted into the cloaca and eliminated along with feces from the intestine.

59 A Closer Look at the Kidney: A Nephron

60 A Closer Look at the Kidney: A Nephron
Filtration approximately 20 percent of the blood gets filtered under pressure through the walls of the glomerular capillaries and Bowman's capsule. filtrate is composed of water, ions (sodium, potassium, chloride), glucose and small proteins filtration process is “much like the making of espresso or cappuccino” water is forced under pressure through a fine sieve containing the filtrate  filtrate enters the Bowman's capsule, it flows through the lumen of the nephron into the proximal tubule.

61 A Closer Look at the Kidney: A Nephron
Reabsorption  inside the lumen of the nephron, small molecules, such as ions, glucose and amino acids, get reabsorbed from the filtrate Proteins called “transporters” located on nephron membrane Grab small molecules as they pass by; each transporter grabs 1 or 2 types of molecules; some transpoters require energy (active), some do not (passive)

62 A Closer Look at the Kidney: A Nephron
Secretion transfer of materials from peritubular capillaries to renal tubular lumen; caused by active transport. Usually ouly a few substances are secreted; substances are present in great excess , or are natural poisons.

63 A Closer Look at the Kidney: A Nephron
Excretion Small toxicants (both polar and lipid-soluble) filtered with ease by the glomerulus. Large molecules (including some that are protein-bound) may be secreted (by passive transfer) from the blood across capillary endothelial cells and nephron tubule membranes to enter the urine. Substances that are ionized remain in the urine and leave the body. Lipid-soluble toxicants can be reabsorbed and re-enter the blood circulation, which lengthens their half-life in the body and potential for toxicity.

64 Disorders of the Excretory System
Interstitial Nephritis disorder in which the spaces between the kidney tubules become swollen (inflamed). may be temporary (acute), or it may be long-lasting (chronic) and get worse over time. may be caused by: Allergic reaction to a drug (acute interstitial allergic nephritis) Autoimmune disorders such as anti-tubular basement membrane disease, Kawasaki’s disease, Sjogren syndrome, systemic lupus erythematosus, or Wegener’s granulomatosis Infections Long-term use of medications such as acetaminophen (Tylenol), aspirin, and nonsteroidal anti-inflammatory drugs (NSAIDS). This is called analgesic nephropathy. Side effect of certain antibiotics (including penicillin, ampicillin, methicillin, sulfonamide medications, and others) Side effect of other medications such as furosemide, thiazide diuretics, omeprazole, triamterene, and allopurinol Too little potassium in your blood Too much calcium or uric acid in your blood

65 Disorders of the Excretory System
Interstitial Nephrities: Signs and Symptoms can lead to acute kidney failure half of the cases will have decreased urine output common signs include: Blood in the urine Fever Increased or decreased urine output Mental status changes (drowsiness, confusion, coma) Nausea, vomiting Rash Swelling of the body, any area Weight gain (from retaining fluid)

66 Disorders of the Excretory System
Interstitial Nephritis: Prevalence/100,000 inhabitants

67 Disorders of the Excretory System
Interstitial Nephritits: Treatment Options Treatment depends on the cause of the problem. Avoiding medications that lead to this condition may relieve symptoms quickly. Limiting salt and fluid in the diet can improve swelling and high blood pressure. Limiting protein in the diet can help control the buildup of waste products in the blood (azotemia) that can lead to symptoms of acute kidney failure. If dialysis is necessary, it usually is required for only a short time. Corticosteroids or stronger anti-inflammatory medications such as cyclophosphamide can sometimes be helpful.

68 Disorders of the Excretory System
Kidney Stones small, hard deposits that form inside your kidneys, made of mineral salts some may need nothing more than to take pain medication and drink lots of water to pass a kidney stone. other instances, surgery may be needed.

69 Disorders of the Excretory System
Kidney Stones: Signs and Symptoms Severe pain in the side and back, below the ribs Pain that spreads to the lower abdomen and groin Pain that comes in waves and fluctuates in intensity Pain on urination Pink, red or brown urine Cloudy or foul-smelling urine Nausea and vomiting Persistent urge to urinate Urinating more often than usual Fever and chills if an infection is present

70 Disorders of the Excretory System
Kidney Stones: Prevalence Each year in the United States, people make more than a million visits to health care providers and more than 300,000 people go to emergency rooms for kidney stone problems

71 Disorders of the Excretory System
Kidney Stones: Treatment Options Drinking water.  Pain relievers.  Medical therapy.  Using sound waves to break up stones.  Surgery to remove very large stones in the kidney.

72 The Immune System

73 Function System of biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents: viruses, parasitic worms, and distinguish them from the organism's own healthy tissue. Consists of: Fluid Immunity: The Blood System and Lymph System Innate Immunity: Surface Barriers or Mucosal Immunity, Normal Flora, Phagocytes Adaptive or Acquired Immunity Cell-mediated Immunity and Humoral Immunity

74 Immunity: The Fluid System
The Blood System Hemocytoblasts mature into three types of blood cells: erythrocytes (red blood cells or RBCs), leukocytes (white blood cells or WBCs), and thrombocytes (platelets). The leukocytes are further subdivided into granulocytes agranulocytes. The granulocytes consist of neutrophils, eosinophils, and basophils. The agranulocytes are lymphocytes (consisting of B cells and T cells) and monocytes.

75 Immunity: The Fluid System
The Blood System Lymphocytes circulate in the blood and lymph systems, and make their home in the lymphoid organs. White blood cells play an important role in phagocytosis of intruders.

76 Immunity: The Fluid System
The Lymph System Lymph is an alkaline fluid that is usually clear, transparent, and colorless. It flows in the lymphatic vessels and bathes tissues and organs in a protective covering. The human lymphoid system has the following: primary organs: bone marrow and the thymus gland (located behind the breastbone above the heart) secondary organs at or near possible portals of entry for pathogens: adenoids, tonsils, spleen, lymph nodes (along the lymphatic vessels with concentrations in the neck, armpits, abdomen, and groin), Peyer's patches (within the intestines), and the appendix.

77 Immunity: Recognition of Pathogens
An antigen is any substance that elicits an immune response, antibodies recognize/differentiate antigens Parts of the immune system are: antigen-specific: they recognize and act against particular antigens systemic: not confined to the initial infection site, but work throughout the body some have memory: recognize and mount an even stronger attack to the same antigen the next time Self/non-self recognition through major histocompatibility complex (MHC). Cells not displaying this is treated as non- self and attacked. Sometimes this process breaks down and the immune system attacks self-cells, known as autoimmune diseases  Some immune response to harmless substances is extreme, known as allergies

78 Immunity: Innate Immunity
Innate Immnunity Immune system we are born with, consisting of: Surface Barriers or Mucosal Immunity: skin, cilia movement in lungs (coughing), sticky mucus, acidic secretions in stomach and various other parts of the body, lyzozyme in saliva, tears, and nasal secretions. Normal Flora in the Intestines: many different types of bacterium Macrophages: participate in phagocytosis

79 Immunity: Acquired Immunity
Consists of lymphocytes: B cells and T cells Blood contains 20–50% of circulating lymphocytes, the rest move in the lymph system. 80% of them are T cells, 15% B Lymphocytes constitute 20–40% of the body's WBCs. Their total mass is about the same as that of the brain or liver. B cells are produced in the stem cells of the bone marrow. Produce antibody and oversee humoral immunity.  T cells are nonantibody-producing lymphocytes which are also produced in the bone marrow but sensitized in the thymus and constitute the basis of cell- mediated immunity. Parts of the immune system are changeable and can adapt to better attack the invading antigen. Two fundamental adaptive mechanisms: cell-mediated immunity and humoral immunity.

80 Immunity: Innate vs. Acquired

81 Immunity: Active Immunity
Type of immunity or resistance developed in an organism by own production of antibodies in response to an exposure to an antigen, a pathogen or to a vaccine. Active immunity is generally long-term Can be acquired by infection followed by B cells and T cells activation, or artificially acquired by vaccines, immunization. Active immunity often involves humoral immunity (B-cells) and cell-mediated immunity (T-cells).

82 Immunity: Passive Immunity
Type of immunity acquired by the transfer of antibody from one individual to another, (i.e. mother to offspring). Two routes: Naturally acquired passive immunity Artificially acquired passive immunity. Passive immunity acquired naturally happens when a mother transfer antibodies to her offspring via placental route during pregnancy and via colostrum during breastfeeding. Passive immunity acquired artificially is done by injecting antibodies to an organism via a vaccination

83 Immunity: Active vs. Passive Immunity
ACTIVE IMMUNITY PASSIVE IMMUNITY Acquired through YOUR OWN body’s formation of antibodies after dieasease, or vaccination Long-term Acquired through passing of antibodies through placenta or breastfeeding Originally immunity may have been acquired through disease resistance or vaccination May be acquired through vaccination

84 Immunity: Humoral Immunity
Immature B-lymphocyte stimulated to maturity when an antigen binds to its surface receptors and helper T-cell nearby (to release a cytokine). Sensitizes or primes the B-cell; undergoes clonal selection, which means it reproduces asexually by mitosis. Clones become plasma cells. Antibodies, (immunoglobulins or Igs)  Soluble proteins secreted by the plasma offspring (clones) of primed B-cells. Inactivate antigens by: complement fixation: proteins attach to antigen surface and cause holes to form, i.e., cell lysis neutralization: binding to specific sites to prevent attachment aglutination: clumping precipitation: forcing insolubility and settling out of solution)

85 Immunity: Cell-mediated Immunity
Macrophages engulf antigens, process them internally, then display parts of them on their surface together with some of their own proteins. Sensitizes the T-cells to recognize antigens. T cells are primed in the thymus. Cytotoxic or killer T-cells: release lymphotoxins, which cause cell lysis.  Helper T-cells: serve as managers, directing the immune response. Secrete chemicals called lymphokines that stimulate cytotoxic T-cells and B-cells to grow and divide, attract neutrophils, and enhance the ability of macrophages to engulf and destroy microbes. Suppressor T-cells: inhibit the production of cytotoxic T cells once they are unneeded, lest they cause more damage than necessary.  Memory T-cells: program to recognize and respond to a pathogen once it has invaded and been repelled.

86 Immunity: Humoral vs Cell-mediated
B-cells differentiate to create antibodies that attack pathogens in various methods (see Humoral Immunity) Responses are specific for a particular antigen Result in long-term memory, both rely on lymphocytes. Various T-cells function in different ways to destroy and remember pathogens (see Cell-mediated Immunity)

87 Immunity: A Closer Look at Lymphocytes
B-CELLS T-CELLS Integral membrane proteins. Present in thousands of identical copies exposed at the cell surface. Encoded by genes assembled by the recombination of segments of DNA. Unique binding site. Bind soluble antigens Bound antigen molecules are engulfed into the B-cell by receptor-mediated endocytosis. The antigen is digested into fragments which are then displayed at the cell surface Recognize their cognate antigen in a processed form, as a peptide fragment presented by an antigen presenting cell's MHC molecule to the T cell receptor. Antigen destroyed by participation of many forms of T-cells

88 Immunity: A Closer Look at Lymphocytes

89 Immunity: Bacteria, Virus, and Antibiotics
Selective poison: Chosen to kill the desired bacteria, but not the cells in your body. Each different type of antibiotic affects different bacteria in different ways. Antibiotics do not work on viruses because viruses are not alive, whereas bacterium is a living, reproducing lifeform. Virus is solely  DNA (or RNA). With a virus there is nothing to "kill," so antibiotics don't work on it.

90 Disorders of the Immune System
HIV/AIDS Chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV). Damages immune system. Sexually transmitted infection. Spread throug infected blood, or from mother to child during pregnancy, childbirth or breast-feeding. May take years before HIV weakens your immune system to the point that you have AIDS.

91 Disorders of the Immune System
HIV/AIDS: Signs & Symptoms Primary infection  Fever Muscle soreness Rash Headache Sore throat Mouth or genital ulcers Swollen lymph glands, mainly on the neck Joint pain Night sweats Diarrhea Due to flu-like, mild symptoms, the first infection stage is usually unnoticed by people.

92 Disorders of the Immune System
HIV/AIDS: Signs & Symptoms Progression to AIDS  Soaking night sweats Shaking chills or fever higher than 100 F (38 C) for several weeks Cough and shortness of breath Chronic diarrhea Persistent white spots or unusual lesions on your tongue or in your mouth Headaches Persistent, unexplained fatigue Blurred and distorted vision Weight loss Skin rashes or bumps

93 Disorders of the Immune System
HIV/AIDS: Prevalence 2010 estimated 1,148,200 persons aged 13 and older were living with HIV infection in the United States, including 207,600 (18.1%) persons whose infections had not been diagnosed.

94 Disorders of the Immune System
HIV/AIDS: Treatment There's no cure for HIV/AIDS, but a variety of drugs can be used in combination to control the virus. Each of the classes of anti-HIV drugs blocks the virus in different ways. Non-nucleoside reverse transcriptase inhibitors (NNRTIs). Nucleoside reverse transcriptase inhibitors (NRTIs).  Protease inhibitors (PIs).  Entry or fusion inhibitors.  Integrase inhibitors. 

95 Disorders of the Immune System
Lupus Lupus is a chronic inflammatory disease that occurs when your body's immune system attacks your own tissues and organs. Inflammation caused by lupus can affect many different body systems — including your joints, skin, kidneys, blood cells, brain, heart and lungs.

96 Disorders of the Immune System
Lupus: Signs & Symptoms No two cases of lupus are alike, but common signs include: Fatigue and fever Joint pain, stiffness and swelling Butterfly-shaped rash on the face that covers the cheeks and bridge of the nose Skin lesions that appear or worsen with sun exposure Fingers and toes that turn white or blue when exposed to cold or during stressful periods (Raynaud's phenomenon) Shortness of breath Chest pain Dry eyes Headaches, confusion, memory loss

97 Disorders of the Immune System
Lupus: Prevalence Primarily a disease of young women Occurs from infancy to old age, with peak occurrence between ages 15 and 40 Blacks (and possibly Hispanics, Asians, and Native Americans) are affected more than whites. Although there is a strong familial aggregation, the disease is relatively uncommon and most cases are sporadic. May occur with other autoimmune conditions Ranges as high as 1,500,000. 2006 study estimated a prevalence of 161,000 with definite SLE and 322,000 with definite or probable SLE 

98 Disorders of the Immune System
Lupus: Treatment Treatment for lupus depends on your signs and symtoms. Medications most commonly used include: Nonsteroidal anti-inflammatory drugs (NSAIDs) Antimalarial drugs Corticosteroids Immune suppressants

99 The Nervous System

100 Function Part of the body that coordinates the voluntary and involuntary actions and transmits signals between different parts of its body. Usually consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS contains the brain and spinal cord. The PNS consists mainly of nerves, which are long fibers that connect the CNS to every other part of the body. The PNS includes motor neurons, mediating voluntary movement, the autonomic nervous system, comprising the sympathetic nervous system and the parasympathetic nervous system.

101 The Central Nervous System (CNS)
Part of the nervous system that combines the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian It contains the majority of the nervous system and consists of the brain and the spinal cord. 

102 The Peripheral Nervous System (PNS)
Consists of the nerves and ganglia outside of the brain and spinal cord. Mainly functions to connect CNS to the limbs and organs. Divided into the somatic nervous system and the  autonomic nervous system. The cranial nerves are a major part of the PNS.

103 A Closer Look: The Neuron

104 A Closer Look: Reflex Arc
Stimulus received from outside stimulates sensory neuron to transmit signal to the spinal cord which conveys the message to a motor neuron which causes a muscle to move.

105 A Closer Look: The Brain

106 Sodium, Potassium, Action: The Physiology of a Nerve Impulse
Polarization of the neuron's membrane: Sodium is on the outside, and potassium is on the inside.  The outside of the cell contains excess sodium ions (Na+); the inside of the cell contains excess potassium ions (K+).

107 The Physiology of a Nerve Impulse
2. Resting potential allows neuron to wait for stimuli. When the neuron is inactive and polarized, it's said to be at its resting potential. It remains this way until a stimulus comes along.

108 The Physiology of a Nerve Impulse
3. Action potential: Sodium ions move inside the membrane. Stimulus allows gated ion channels to open suddenly and allow the Na+ that was on the outside of the membrane to go rushing into the cell. As this happens, the neuron goes from being polarized to being depolarized. Each neuron has a threshold level — the point at which there's no holding back.

109 The Physiology of a Nerve Impulse
Repolarization: Potassium ions move outside, and sodium ions stay inside the membrane. After concentration of Na+, the gated ion channels on the inside of the membrane open to allow the K+ to move to the outside of the membrane. With K+ moving to the outside, the membrane's repolarization restores electrical balance, although it's opposite of the initial polarized membrane that had Na+ on the outside and K+ on the inside. Just after the K+ gates open, the Na+ gates close; otherwise, the membrane couldn't repolarize. Hyperpolarization: More potassium ions are on the outside than there are sodium ions on the inside. When the K+ gates finally close, the neuron has slightly more K+ on the outside than it has Na+ on the inside. This causes the membrane potential to drop slightly lower than the resting potential, and

110 The Physiology of a Nerve Impulse
Refractory period puts everything back to normal: Potassium returns inside, sodium returns outside. The refractory period is when the Na+ and K+ are returned to their original sides: Na+ on the outside and K+ on the inside.

111 Neurotransmitters Neurotransmitters are chemicals that transmit signals from a neuron to a target cell across a synapse. Neurotransmitters are packaged into synaptic vesicles  on the presynaptic side of a synapse. They are released into and diffuse across the synaptic cleft, where they bind to specific receptors in the membrane on the postsynaptic side of the synapse. Release of neurotransmitters usually follows arrival of an action potential at the synapse, but may also follow graded electrical potentials.

112 Neurotransmitters: IPSP vs. EPSP
Less likely to generate action potential Associated with influx of Cl- or efflux of K+ Moves farther from the threshold. -Types of synaptic potential gradients. More likely to generate action potential Associated with influx of Na+ Moves closer to the threshold.

113 Disorders of the Nervous System
Alzheimer’s Disease Progressive disease that destroys memory and other important mental functions. Most common cause of dementia — a group of brain disorders that results in the loss of intellectual and social skills. Connections between brain cells and the brain cells themselves degenerate and die, causing a steady decline in memory and mental function.

114 Disorders of the Nervous System
Alzheimer’s Disease: Signs & Symptoms Forgetfulness and/or mild confusion Memory lapses Disorientation and misinterpreting spatial relationships Trouble speaking and writing, thinking and writing, making judgments and decisions, performing familiar tasks Personality changes Depression Social withdrawal Mood swings Distrust in others Irritability and aggressiveness Changes in sleeping habits Wandering Loss of inhibitions Delusions, such as believing something has been stolen

115 Disorders of the Nervous System
Alzheimer’s Disease: Prevalence Estimated 5.4 million Americans of all ages have AD(2012). 5.2 million people age 65 and older, 200,000 individuals under age 65 who have younger-onset Alzheimer’s. One in eight people age 65 and older Nearly half of people age 85 and older Most are non-Hispanic Caucasian Americans

116 Disorders of the Nervous Sytem
Alzheimer’s Disease: Treatment AD is not curable, but can be offset. Drugs Cholinesterase inhibitors Memantine Creating a safe & supportive environment Exercise & nutrition


118 Disorders of the Nervous System
Multiple Sclerosis Multiple sclerosis (MS) is a potentially debilitating disease in which your body's immune system eats away at the protective sheath (myelin) that covers your nerves. Damage to myelin causes interference in the communication between your brain, spinal cord and other areas of your body. This condition may result in deterioration of the nerves themselves, a process that's not reversible.

119 Disorders of the Nervous System
Multiple Sclerosis: Signs & Symptoms Various types of symptoms, including: Numbness or weakness in one or more limbs Partial or complete loss of central vision, usually in one eye, often with pain during eye movement (optic neuritis) Double vision or blurring of vision Tingling or pain in parts of your body Electric-shock sensations that occur with certain head movements Tremor, lack of coordination or unsteady gait Slurred speech Fatigue Dizziness Heat sensitivity

120 Disorders of the Nervous System
Multiple Sclerosis: Prevalence Affects more than 350,000 people in the United States and 2.5 million worldwide. In the United States, 90 per 100,000 population. MS symptoms can start anywhere between 10 and 80 years of age, but usually between 20 and 40 years. Women outnumber men by a ratio of almost 2 to 1 Affects Caucasians more than African Americans

121 Disorders of the Nervous System
Multiple Sclerosis: Treatment Drugs Corticosteroids and plasma exchange treat MS attacks Beta interferon, glatiramer acetates, fingolimod, natalizumab, mitoxantrone, and teriflunomide slow progression of the disease Physical therapy and muscle relaxants target physical symptoms

122 Bibliography

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