Circulatory System Reveiw

1. Explain the concept of homeostasis and its critical nature to living things.

 Homeostasis: the bodys maintenance of a relatively stable internal physiological environment; the steady state resulting from conditions inside every cell remaining nearly constant.

Homeostasis is critical to living things because multicellular organisms must maintain near constant conditions throughout their internal environment so that all of their individual cells can continue working together. Example: the cells of the human body are surrounded by a fluid having a salinity nearly equal to that of the Earths oceans. The salinity and pH of the interstitial fluid, or fluid in the pores between our cells, must be relatively constant in order for the cells of the body to remain healthy.

2.     Explain the importance of temperature regulation in maintaining a homeostasis with reference to negative feedback loops and positive feedback loops.

A negative feedback loop is a process that detects and reverse deviations from normal body constants. This process involves three parts: a receptor, and integrator and an effector. The function of the sensory receptors is to send nerve impulses 9stimuli) to the brain in response to environmental information. They monitor the bodys internal conditions, such as temperature. For instance, when the bodys temperature begins to drop or rise, specialized receptors in the skin detect the change and signal the hypothalamus.

The brain is an integrator. It sends messages to the effectors. Effectors, in turn, cause a change in internal conditions. In this case, the brain sends messages to various tissues and organs that cause the body to either generate or conserve heat.

Positive feedback loops also exist, but they are usually associated with disease or change. (for example, drug addiction) and are therefore rare in healthy bodies. Positive feedback loops act to increase the strength in the stimuli, whereas negative feedback loops decrease and reverses effects of the stimuli. A negative feedback loop moves a system toward balance and stability, while a positive feedback loop pushes a system away from it.

3.     Explain the need for a transport system.

The transport system helps maintain healthy conditions in the interstitial fluid surrounding each cell by transporting nutrients, respiratory gases and wastes.

Artery: blood vessel that carries blood away from the heart.

Vein: in animals, a blood vessel that carries blood to the heart.

Capillary: tiny blood vessel with a wall only a single cell think. Gases and other substances are exchanged between the circulatory system and the tissues of the blood across the capillary walls.

6. Identify the main components of the human heart and explain the role of each:

Atria: has the job of pushing blood into the adjacent ventricles. It has relatively thin walls and do not generate much force.

Ventricles: have thicker walls than the atria with muscular walls that can push blood out through blood vessels and capillary beds in the pulmonary and systemic circulatory systems.

Bicuspid Valve: the valve located between the left atrium and the left ventricle of the heart; called bicuspid because the valve has two parts. One of the valves that prevent blood from flowing the wrong way through the cardiac cycle.

Tricuspid Valve: the valve located between the right atrium and the right ventricle of the heart; called tricuspid because the valve has three parts. One of the valves that prevent blood from flowing the wrong way through the cardiac cycle.

Pulmonary Semilunar Valve: located at the beginning of the pulmonary artery. It permits blood flow in only one direction, allowing blood to flow out of the right ventricle, but prevent it from backflowing into the ventricle.

Aortic Semilunar Valve: situated at the beginning of the aorta. It permits blood to flow in one direction, allowing blood to flow out of the left ventricel up into the aorta, but prevent backflow into the ventricle.

Aorta: The major artery carrying oxygenated blood away from the heart.

Pulmonary Artery: arteries that can carry deoxygenated blood to the lungs from the heart.

Pulmonary Vein: veins that carry oxygenated blood from the lungs to the heart.

7 Trace the flow of blood through the heart (Cardiac pathway) an then describe the systemic and pulmonary pathways.

(Starting with right atrium) Right atrium, right ventricle, pulmonary artery to lungs, pulmonary veins, left atrium, left ventricle, aorta to body cells to vena cava and repeat.

Pulmonary Circulation: the pathway of the blood from the heart to the lungs and back. One of the three primary cycles in the mammalian circulatory system.

Systemic Circulation: the path taken by the blood as it flows from the heart to the rest of the body and back. One of the three primary cycles in the mammalian circulatory system.

8. Describe disorders linked to the circulatory system and their effect on the homeostasis of the system and the organism as a whole:

Hypertension: chronically elevated blood pressure, often associated with a number of health problems such as greatly increased risk of stroke and heart disease.

Atherosclerosis: narrowing if the arteries due to the deposit of cholesterol-rich plaques on the innermost layer of the all of an artery; results in decreased blood flow.

Arteriosclerosis: a condition related to athersclerosis in which cholesterol or fatty material becomes deposited under the inner lining of the arteries; results in blockage of blood flow in the artery.

Coronary Blockage:

9.     Describe the treatment of circulatory disorders with reference to such techniques as Shunts, Angioplasty and Clot busting.

Angioplasty: surgical procedure in which a cardiologist inserts a fine plastic tubes into a clogged artery and then inflates part of the tube, opening the artery.

Coronary Bypass: surgical procedure that involves removing a segment of healthy blood vessel from another part of the body and using it to create a new pathway (shunt) around the blockage in a blood vessel near the heart.

Clot busting: medicines that open up the coronary arteries, restoring blood flow to the heart, increasing the oxygen level in the heart, and preventing tissue death.

5.     Identify the main components of blood and explain the characteristics and role of each:

Erythrocyte: also known as a red blood cells. Blood cells that are specialized for oxygen transport.

Leukocyte: white blood cells that protect the body from invasion of foreign substances such as bacteria.

Platelets: component of the blood consisting f fragments of cells that were created when larger cells in the bone marrow broke apart.  They contain no nucleus and break down quickly in the blood.

Plasma: fluid portion of the blood. Plasma is made up of water plus dissolved gases, proteins, sugars, vitamins, minerals, and waste products.

Excretory System Reveiw

1. How do the following act as organs of excretion:

Lungs: remove carbon dioxide from the body

Liver: removes metabolic wastes

Skin: removes excess heat and maintains a balanced body temperature

Kidney: look at number 2

2. The kidneys principal function is to filter the blood in order to remove cellular waste products from the body. This organ is usually associated with the excretion of cellular waste. The main metabolic wastes are urea, uric acid, and creatinine, all of which have nitrogen as a major component.

6. Disorders:

Bladder infections:

One of the most common disorders of the excretory system is a urinary tract infection. If the bladder is infected, the disorder is called cystitis. If only the urethra is affected, it is called cystitis. Urinary infections are more common in women then in men, due to the fact that in females the urethral and anal openings are closer together.

The symptoms include painful urination with a burning sensation, a need to urinate frequently even if no urine is present, and bloody or brown urine. The upper abdomen or lower back may be tender, and chills, fever, nausea and vomiting may be present.

Kidney infections:

If the infection of the urinary tract reaches the kidneys, the disorder is called pyelonephritis. Some causes are an obstruction in the prostate, and an infection that has travelled from elsewhere in the body, often the bladder. The most common cause in children is a problem with the connection between the tube that drains urine from the kidneys and the bladder. It can usually be treated with antibiotics, but in a serious case, surgery may be needed. Preventative measures include maintaining hygienic personal behaviours.

Kidney Stones

Kidney stones form when chemicals in the urine precipitate out and form crystals. They are more common in men. Common factors include recurrent urinary tract infections, insufficient water, consumption, low activity levels, and the intake of too much vitamin C and D. They often reoccur, so its important to follow medical advice to avoid forming more. Symptoms include severe pain in the small of the back or the abdomen, blood in the urine, nausea and vomiting. Many stones will pass through on there own or to can be treated with lithotripsy. If the stones are larger, surgery may be needed to remove them.

Respiratory System

Respiratory Illnesses

Lung Cancer

Passage of air through human respiration system

nasal cavity pharynx epiglottis -  larynx esophagus trachea bronchus bronchiole alveoli

Role of the Lung

All lung systems consist of three basic elements: one or two lungs that have a moist respiratory surface; some means of forcible bringing air in contact with the lung surface; and a circulatory system to carry the gases between the lungs and the other cells of the body.

Requirements of the respiratory system

The surface area available for gas exchange, or respiratory surface, must be big enough for the exchange of oxygen and carbon dioxide to occur at a rate that will meet the organisms metabolic needs. Second, respiration must take place in a moist environment, so that the oxygen and carbon dioxide are dissolved.

Gas exchange

The wall of each sac (alveoli) is one cell thick and is adjacent to a network of tiny capillaries. These capillaries are the site for the exchange of oxygen and carbon dioxide in the body. While most of the exchange takes place through simply diffusion, a process of facilitated diffusion accounts for some of the oxygen transfer. This allows the blood to take up oxygen more quickly than would otherwise be possible. (Fig. 10.7 p.337)

The mechanics of inhalation and exhalation of breath

Circulatory and Respiration Terms

Chapter 9

Homeostasis: the bodys maintenance of a relatively stable internal physiological environment; the steady state resulting from conditions inside every cell remaining nearly constant.

Dynamic equilibrium: state if balance achieved within an environment as the result of internal control mechanisms that continuously oppose outside forces that tend to change that environment.

homeotherm: animals that keeps its body temperature relatively constant, such as birds and  mammals.

Poikilotherm: animals that has a body temperature that fluctuates depending on the temperature of the animals environment.

Vasoconstriction: decrease in the diameter of blood vessels. The constriction of blood vessels near the skin conserves in the core of the body to keep the major organs functioning.

Vasodilation: expansion of the diameter of blood vessels. The dilation of blood vessels near the skin brings more blood to the surface to help reduce body temperature.

Negative Feedback loop: homeostatic mechanism that detects and reserves deviations from normal homeostasis levels. The mechanism consists of sensory receptors, an interator, and effectors.

Sensory receptors: cells or group of cells scattered throughout the body that work continually to receive information about the bodys internal conditions such as temperatures, pH, glucose levels and blood pressure.

Integrator: in the nervous system, describes the function of the hypothalamus in the brain that receives messages from receptors and sends instructions to effectors.

Effector: in the nervous system, structure the receives information from the homeostasis integrator, and makes changes to the bodys internal conditions.

Cardiac Circulation: the route taken by blood vessels in the heart. One of three primary cycles in the mammalian circulatory system.

Pulmonary Circulation: the pathway of the blood from the heart to the lungs and back. One of the three primary cycles in the mammalian circulatory system.

Systemic Circulation: the path taken by the blood as it flows from the heart to the rest of the body and back. One of the three primary cycles in the mammalian circulatory system.

Artery: blood vessel that carries blood away from the heart.

Vein: in animals, a blood vessel that carries blood to the heart.

Capillary: tiny blood vessel with a wall only a single cell think. Gases and other substances are exchanged between the circulatory system and the tissues of the blood across the capillary walls.

Plasma: fluid portion of the blood. Plasma is made up of water plus dissolved gases, proteins, sugars, vitamins, minerals, and waste products.

Erythrocyte: also known as a red blood cells. Blood cells that are specialized for oxygen transport.

Leukocyte: white blood cells that protect the body from invasion of foreign substances such as bacteria.

Macrophage: phagocytic cell that can pass through the walls of capillaries to engulf and digest pathogens such as bacteria circulating within the body.

Lymphocyte: type of blood cell that plays a role in the bodys acquired immune response, enabling the bodys to recognize and fend off specific pathogens.

Platelets: component of the blood consisting f fragments of cells that were created when larger cells in the bone marrow broke apart.  They contain no nucleus and break down quickly in the blood.

Fibrin: insoluble material that forms a mesh of strands around the area of an injury prevent the loss of blood from damaged blood vessels.

Superior Vena cava: the main blood vessel that collects from the systemic circulation of the body and returns it to the right atrium of the heart, which pumps the blood into the right ventricle.

Bicuspid Valve: the valve located between the left atrium and the left ventricle of the heart; called bicuspid because the valve has two parts. One of the valves that prevent blood from flowing the wrong way through the cardiac cycle.

Tricuspid Valve: the valve located between the right atrium and the right ventricle of the heart; called tricuspid because the valve has three parts. One of the valves that prevent blood from flowing the wrong way through the cardiac cycle.

Sinoatrial (S-A) Node: bundle of specialized muscle tissue (also known as the pacemaker), located in the wall of the right atrium of the mammalian heart. The S-A node generates an electrical impulse that stimulates the muscle fibers to contract and relax rhythmically, producing a regular heartbeat.

Atrioventricular (A-V) node: node, located near the atria of the partition  between the two impulse over the walls of the ventricle to start their contraction.

Cardiac Output: amount of blood pumped by the heart, usually measured in ml/min. Cardiac output= stroke volume * heart rate.

Stroke Volume: amount of blood forced out of the heart with each heartbeat.

Septum: in the heart, wall that separates the right and left ventricles.

Lymphatic Circulatory system: network of glands and vessels that carry lymph throughout the mammalian body.

Lymph: colorless or pale yellow fluid that circulates throughout the lymphatic circulatory system.

Systolic Pressure: the highest pressure in the cardiac cycle, generated by the contraction of the left ventricle as it forces blood out of the heart.

Diastolic Pressure: pressure in the circulatory system when it reaches its lowest point immediately before another contraction of the ventricles.

Hypertension: chronically elevated blood pressure, often associated with a number of health problems such as greatly increased risk of stroke and heart disease.

Atherosclerosis: narrowing if the arteries due to the deposit of cholesterol-rich plaques on the innermost layer of the all of an artery; results in decreased blood flow.

Arteriosclerosis: a condition related to athersclerosis in which cholesterol or fatty material becomes deposited under the inner lining of the arteries; results in blockage of blood flow in the artery.

Angioplasty: surgical procedure in which a cardiologist inserts a fine plastic tubes into a clogged artery and then inflates part of the tube, opening the artery.

Coronary Bypass: surgical procedure that involves removing a segment of healthy blood vessel from another part of the body and using it to create a new pathway (shunt) around the blockage in a blood vessel near the heart.

Chapter 10

Aerobic: requiring molecular oxygen (O2) to maintain cellular functions.

Gas Exchange: process of exchanging respiratory gases. Gas exchange is the fundamental objective of all respiratory systems.

respiratory Surface: any surface across which gases are exchanged for the purpose of respiration.

Lung: respiratory structure contained entirely within the body of an animal, and connected to the outside air by means of internal passageways.

Trachea: in vertebrates, tube that carries air from the nasal passages or mouth to the lungs; also known as the windpipe.

Pharynx: structure located just behind the mouth that connects the mouth and nasal cavity t the larynx and esophagus.

Glottis: in mammals, the opening of the trachea through which air enters the larynx.

Epiglottis: in mammals, a flap located over the entrance to the trachea. The epiglottis closes the respiratory tract.

Larynx: in mammals, a structure within the upper respiratory tract that contains the vocal cords. Also commonly known as the voicebox.

Bronchi: in a mammal, the passageways that branch from the tracheae into the lungs. One bronchus carries air into each lung.

Bronchioles: in a mammal, the passageways that branch from the bronchi into the separate lobes of the lungs. The bronchioles divide into smaller and smaller passageways that carry air into all portions of the lungs

Alveoli: the gas exchange structures within mammalian lungs. Alveoli are tiny air pockets with walls made of a membrane a single cell thick. Respiratory gases are exchanged across these membrane walls.

Pleura: the membrane that envelop the lungs. Each lung is encased in two separate pleural membrane separated by a thin layer of fluid.

Intercostal Muscles: muscles of the rib cage. In mammals, these muscles help to expand and contract the rib cage and play an important role in breathing.

Diaphragm: in mammals, a muscle layer that forms the floor of the thoracic cavity. The contraction of the diaphragm contributes to inspiration by increasing the volume of the thoracic cavity.

Lung Capacity: volume of air drawn in or pushed out by the lungs.

Tidal Volume: volume of air drawn in and pushed out by the lungs in a normal breathing movement.

Inspiratory reverse Volume: additional volume of air that can be forcibly taken in by the lungs, beyond a regular, or tidal, inhalation.

Expiratory Reserve Volume: additional volume of air that can be forced out by the lungs, beyond a regular, or tidal, exhalation.

Vital capacity: total volume of gas that can be moved in or out of the lungs. It can be calculated as tidal volume+inspiratory reserve volume + expiratory reverse volume = vital capacity.

Residual Volume: amount of gas that remains in the lungs and the passageways of the respiratory system even after a full exhalation.

respiratory Efficiency: rate at which oxygen can be transferred from the respiratory surface to the internal transport system or tissues of an animal.

Lung Cancer: uncontrolled and invasive growth of abnormal cells in the lungs.

Carcinoma: malignant tumor.

Carcinogens: cancer-causing agents.

Pneumonia: disease of the lungs that causes the alveoli (air sacs) in the lungs to inflame and fill with liquids. This impairs their ability to take in oxygen, so body cells become oxygen starved.

Mycoplasma pneumonia: type of pneumonia caused by mycoplasmas, which are the smallest free-living agents of disease in humans.

Asthma: chronic obstructive lung disease that can develop at any age; characterized by extreme sensitivity of the lungs to certain triggers that cause the airways to react and become obstructed.

Chronic Bronchitis common obstructive respiratory disorder in which the airways are inflamed and filled with mucous. Commonly, a cough brings up the mucous and infection is likely to occur.:

Emphysema: chronic, incurable obstructive respiratory disorder in which the alveoli are distended and their walls so damaged that the surface available for gas exchange is reduced and less oxygen is available to the brain and tissues.

Digestion, Excretory and Immunity Terms

Essential Nutrients: chemical substances taken or derived from food than can be used by an organism to sustain its life processes

Heterotrophs: organism that must derive some of its nutrients from organic molecules formed  by autotrophs.

Autotrophs: organism that can produce organic molecules from simple inorganic molecules and thus make it own food.

Digestive System: system inside animals in which food is taken in and broken down to the point at which useful substances can be absorbed into and transported by the circulatory system to individual cells.

Balanced Diet: a healthy diet containing six essential nutrients (carbohydrates, fats, proteins, minerals, vitamins, and water) in the amounts that keep body and mind functioning at their best.

Complete Protein: protein that contains all of the eight essential amino acids. It can be found in meat, legumes, eggs, cheese, milk, and whole grain products.

Minerals: inorganic compounds that the body needs in small amounts to enable certain chemical reactions and the building bones and cartilage.

Vitamins: essential requirement of a healthy diet; required in the body in relatively small amounts, but act as coenzymes and are involved in tissue development and growth and in helping the body to fight and resist disease.

Coenzymes: organic co-factors needed to make enzymes function. Vitamins are part of many coenzymes.

Mechanical digestion: initial stage in digestion, physically breaking down food into smaller pieces.

Chemical Digestion: second main stage in digestion, the separation of food into its molecular components by chemical means. Begins in the mouth, with the secretion of digestive enzymes; continues in the stomach and is completed in the small intestine.

Papillae: tiny pimple-like structures on the upper surfaces of mammalian tongues that house taste buds.

Uvula: small fleshy V-shaped extension of the small palate that hangs above the tongue at the entrance to the throat. Prevents food from entering the pharynx when swallowing.

Saliva: watery secretion of the salivary glands; in addition to containing a starch- digesting enzyme, saliva helps lubricate food so it may be swallowed more easily.

Salivary Glands: three pairs of glands, the parotid, sublingual, and submaxillary, that secrete saliva into the mouth.

Esophagus: tube that connects the mouth to the stomach, lined with both circular and longitudinal muscles.

Stomach: J- shaped sac lying between the esophagus and small intestine whose muscles work to physically break down food; its inner lining also contains millions of gastric glands that release gastric juice, which begins the chemical breakdown of proteins.

Chyme: thick liquid mixture of partially broken down food and gastric juice that passes from the stomach into the duodenum.

Pyloric Sphincter: circular muscle opening that has a single ring structure. The nucleotide bases thymine, cytosine, and uracil are derived from pyrimidines and always bond with purines in DNA

Small intestine: narrow diameter length of the digestive tract between the stomach and the large intestine, comprised of the duodenum, jejunum, and ileum; most products of digestion are reduced to nutrients and absorbed along its length.

Duodenum: shortest, widest, and first section of the small intestine following the stomach; bile and pancreatic juice enter the small intestine here.

Villi: finger- like projections that line the folds of the small intestine and greatly increase its absorptive surface area.

Jejunum: part of the small intestine following the duodenum, contains more folds and intestinal glands than the duodenum.

Ileum: portion of the small intestine, about 3 m long, attached to the large intestine; contains fewer and smaller villi. It absorbs more nutrients as well as pushing remaining undigested food into the large intestine.

Large intestine: final portion of the digestive system, about 1.5 m long, consisting of the caecum, colon, rectum, and anal canal.

Caecum: sac- like portion of the large intestine near the small intestine that has a blind end.

Appendix: appendage that hangs from the caecum portion of the large intestine. It has no role in digestion but may help fight infection.

Colon:

Rectum: with the anal cavity, comprises the last 20 cm of the large intestine.

Anal Canal: the last portion of the large intestine that opens to the anus.

Anus: the opening of the digestive system through which waste passes out of the body.

Peristalsis: movement of food through the digestive tract, accomplished by a series of wavelike contractions and relaxations of the circular and longitudinal muscles that surround the various parts of the digestive tract.

Liver: organ that has many roles in the body. It makes bile salts from cholesterol, stores some excess chemicals collected from the bloodstream, breaks down old red blood cells, and has many roles in digestion, such as stimulating duct cells to release an alkaline fluid containing sodium carbonate and sodium bicarbonate.

Pancreas: small gland near the small intestine, which is made up of two types of tissues that independently function as exocrine and endocrine glands. As an exocrine organ, the pancreas secretes digestive enzymes into the duodenum. As an endocrine organ, it produces insulin and glucagons.

Gall Bladder: organ that stores bile produced by the liver.

Ulcer: slow- healing sore resulting from stomach acid penetrating the protective mucus layer of the stomach wall and causing the wall to begin to erode.

Gallstones: small, hard masses that form in the gallbladder, resulting from cholesterol precipitating out of the bile to form crystals that grow in size.

Ileitis: inflammation of the ileum.

Colitis: inflammation and ulceration of the innermost lining of the colon.

Anorexia Nervosa: eating disorder characterized by a morbid fear of gaining weight, which causes the person to go on a very restrictive diet. Sufferers typically have a body mass less than 85 percent of their normal mass and, due to a distorted body image, see themselves as fat even when emaciated.

Bulimia Nervosa: dangerous eating disorder characterized by recurring episodes of binge eating followed by purging, usually through vomiting or taking laxatives; may be associated with obesity and anorexia nervosa.

Kidney: in vertebrates, either of the two organs that filter the blood to remove nitrogenous waste (which is excreted in the urine) and adjust the concentrations of salts in the blood.

Ureter: in mammals, either of a pair of ducts that carry urine from the kidneys to the bladder.

Cortex: the outer part of the kidney, where the glomerulus, Bowmans capsule, proximal tubule, and distal tubule of the nephrons are located.

Medulla: the inner part of the kidney, where the loop of Henle and the collecting ducts of the nephrons are located.

Pelvis: part of the kidnet where urine accumulates before moving through the ureters.

Nephron: there are about 1 million of there filters in each kidney, each filter consisting of a Bowmans capsule, the glomerulus, a proximal tubule, the loop of Henle, the distal tubule, and a collecting duct.

Bowmans Capsule: the receiving end of the renal tubule at which water and small solutes from the blood wnter the proximal tubule from the glomerulus.

Glomerulus: the blood vessel inside the Bowmans capsule, from which water, salts, nutrient molecules, and water molecules leave the blood to be filtered by the kidney.

Nephrite Filtrate: urine. About 20 percent of the blood plasma that enters the kidneys becomes nephrite filtrate.

Proximal tubule: in a kidney, the tube between the Bowmans capsule and the loop of Henle.

Loop of Henle: the long loop of the nephron that extends into the medulla of the kidney between the proximal tubule and the distal tubule.

Distal Tubule: in a kidney, the tube that connects the loop of Henle to the collecting duct.

Tubular Secretion: process that uses active transport to draw substances, such as hydrogen ions, creatine, and drugs (e.g. penicillin) out of the blood and into the filtrate of the kidney.

Renal Failure: the condition in which an individuals kidneys no longer work properly and wastes accumulate in the blood.

Hemodialysis: or kidney dialysis, medical treatment of kidney failure; the process of removing blood substances, and returning it to a vein.

Immune System: a homeostatic mechanism comprising a variety of white blood cells and proteins that attack foreign invaders such as bacteria and viruses; recognizes and destroys damaged cells and irregular growths.

Immunity: the ability to resist a disease after having been exposed to it in the past.

Non-specific defence: the ability to resist a disease, even if there has been no prior exposure to it.

Pathogens: disease-causing agents (e.g., bacteria or viruses.)

Phagocytosis: process in which a cell swallows and devours another cell, bacterium, or chunk of organic matter through endocytosis.

Macrophage: phagocytic cell that can pass through the walls of capillaries to engulf and digest pathogens such as bacteria circulating within the body.

Neutrophil: small white blood cells (leucocytes) that engulf bacteria through phagocytosis as an immediate immune response.

Monocyte: white blood cell from which neutrophils and macrophages are derived.

Specific Immune system: wide variety of cells, developed through exposure to disease, that recognize certain foreign substances and act to neutralize or destroy them.

Lymphocytes: type of blood cell that plays a role in the bodys acquired immune response, enabling the body to recognize and fend off specific pathogens.

Antibody: a Y- shaped protein molecule that is made up of a heavy polypeptide chain bound to a light polypeptide chain. (Fig 11.27 on 384.)

Antigen: protein or other large molecule in the surface of a non-self cell (attacking or unfamiliar cell) that helps the body recognize the cell as non-self

Histamines: chemicals that increase the permeability of blood vessels, causing reddening and swelling of an area.