Stephanie'sChapter16

__Chapter 16 The Human Animal: Maintenance of Internal Environment__

__Circulation__

__16.1 The Heart Pumps Blood Through a Series of Tubes (p424-p427)__ Arteries – a vessel that transports blood away from the heart Vein – a vessel that carries blood toward the heart Capillaries – a microscopic blood vessel that that penetrates the tissues and that has walls consisting of a single later of cells that allows exchange between the blood and tissue fluids Atrium – a camper of the heart that receives blood from veins Ventricle – one of two chambers of the heart the blood out the heart __16.2 Plasma Contains Blood Cells and Other Substances (p427, p428)__ Plasma – the liquid portion of the blood in which the cells are suspended Blood is 90% water and 10% other dissolved substances. These substances include essential elements, absorbed food molecules (single sugars, amino acids and fatty acids), respiratory gasses (oxygen and carbon dioxide), waste product, and regulatory substances (hormones and enzymes). Haemoglobin –the pigment in red blood cells responsible for transport of oxygen; contains iron White blood cells are the other kind of blood cell in humans. Red and white cells help to make bone marrow Red blood cells have a live span of 110-120days __16.3 Clotting Is an Interaction between Platelets and Plasma Proteins (p428, p429)__ Clotting involves 30 proteins and small cell fragments of platelets Platelets – a small plate-shaped blood factor that contributes to blood clotting at the site of a wound; platelets release substances that begin formation of a network in which the platelets are caught forming a clot __16.4 Some Cells and Materials Move Between Blood Vessels and Tissue (p429)__ White blood cells, water, nutrients, and plasma can move freely between blood vessels and tissues. Red blood cells cannot Fluids from tissue cells(callled lympth) can ooz into the blood capilliaries Lympth vessels in the small intestine absorb fats Metabolic wastes from cells also passes into the lympths Lympths have a higher fat content and waste content then blood All this is part of the Lympathatic system. The Lympathatic system:
 * Circulation
 * Step 1: oxygenated blood leaves the heart through arteries and is pumped to different parts of the body.
 * Step2: Blood makes it to capillaries where it passes from the arteries to the veins though the capillaries. The blood going into the veins has no oxygen in it.
 * Step3: Blood travels through the veins back to the heart.
 * Step4: The de-oxygenated blood is pumped from the heart to the lungs.
 * Step5: The lungs re-oxygenate the blood and it is returned to the heart and the steps are repeated
 * is divide intotine twisted passageways
 * these passageways make up LYMPH NODES
 * lymph pass slowely through the nodes
 * pathogens and foreign matteral can be engolfed by white blood cells in the nodes
 * all lympth vessel join forming a duct near the left shoulder
 * the duct joins with capilliars and the fluids are returned to the blood and pumped into the heart

__Immunity__ __16.5 The Body Has Several Defenses Against Foreign Invaders (p430, p431)__ Immunity – the capacity of the human body to resist most pathogens that might damage tissue and organs. The body has to types of immunity: If the barrier made by the nonspecific protective shield is broken and substances do enter the circulatory system the specific immune response takes over. __16.6 Protect by the Immune System Is Specific (p431-p434)__ The immune system is made up of many structures that interact with the white blood cells. These structures include:
 * 1) Nonspecific protection – skin the covering the body, mucous membranes that line the digestive and respiratory tracts and inflammatory process
 * 2) Specific immune response – which is the immune system

Antigen - a macromolecule that is recognises foreign and elicits an immune response Memory Cells: B or T cells, produced in response to a primary immune response, that remains in the circulation and can respond rapidly of the same antigen is encountered in the future Vaccines are prepared from weakened, dead or closely related or modified pathogens. These are then injected into the body to stimulate production of plasma and memory cells usually without causing system of the disease. __16.7 Many Problems Can Arise with the Immune System (p437 – p440)__ Autoimmune – a response t in which antibodies are produced against some of the body’s own cells __Gas Exchange and Excretion__ __16.8 Cellular Respiration and Gas Exchange Are Not the Same__
 * Lymphocytes – a type of white blood cell that is important thing in the immune system
 * primary cells in the immune system
 * specialize in recognition of foreign substance || [[image:immuesystem.jpg]] ||
 * **B **cells – type of lymphocytes that are formed in the **B **one marrow.
 * They produce antibodies ||^  ||
 * T cells – is type of lymphocytes that migrates to the thymus gland to become a T cells
 * 2 types of T cells:
 * 1) Killer T Cells – Attack infected host directly
 * 2) Helper T Cells – interact with the B cells to make antibodies ||^   ||
 * Macrophage – a large white blood cell that ingest pathogen and dead cells ||^  ||

Cellular respiration is part of gas exchange Diaphragm – the sheet of muscle that separates the chest and abdominal cavity in mammal and, along rib muscles that is important for breathing When you breath in Step 1:diaphragm moves down and your ribs move up and out the chest cavity enlarges. Step 2: When this happens pressure in the cavity falls. Step 3:This causes air to rush in. When you breath out Step 1: volume of the chest cavity is reduced Step2: the pressure increases and air is pushes out Trachea – the windpipe of an air-breathing vertebrate, connecting the air passage in the throat with the lungs. This cleans the air. Alveoli – air sacs in the lungs __16.9 Respiratory Gases Are Transported in the Blood (p443)__ Once oxygen is in the blood it needs to be transported around the body. Hemoglobin is need to do this __16.10 The Kidneys Are Major Homeostatic Organs (p444, p445)__

Kidneys excrete nitrogen compounds, regulate ion concentration and maintain water balance. Nephrons – a functional unit of a kidney, consisting of a long, coiled tubule, one end which forms a cup that encloses a mass of capillaries and the other end of which opens into a duct the collects urine; entire nephron is surrounded by a network of capillaries Glomerulus – a ball of capillaries surrounded by a capsule in the nephron and serving as the site of filtration in the kidney

__16.11 Nephron Filter the Blood (p447, p448)__ Function of a nephron: __Temperature Regulation__ __16.12 The Rate of Chemical Reactions Is Influenced By Temperature (p449)__ Reactions in the body slow down at low temperature and speed up when the body is warmed up. Maintains a constant temperature internally is important for efficient reactions When you wake up your temperature is about 36.2 degrees Celsius and gets to about 37.6 making the average temperature about 37. The body must be able to balance the heat it produce with the lost amount Cellular respiration lets off heat, muscles and organs are the most active tissues in the body, how active they are equals more or less cellular respiration __16.13 Major Heat Loss Occurs Through Evaporation and Radiation (p449, p450)__ 80% or more of the body’s heat is lost mostly through the skin but also in normal functions like respiratory, digestive, and excretory system Evaporation is the way the body cools itself, the more humidity the hard it is for the body to do this Radiated heat is from one object is transferred to another (ex we can feel heat off the sun). This can make us feel heat or the lack of it(cold). __16.14 Internal Temperature Is Controlled by the Brain (p450)__ Heat loss or gain can be affected by anything from the food/drinks we consume to a breeze. Body temperature can only be constant if the rate of heat produced is the same as heat lost It only takes a change of .01 degree Celsius to cause the body to change how much heat it is keeping of losing. If the temperature is raised the body sweets more if the temperature is dropped the body slows the amount it sweets and constricts blood flow to extremities.
 * 1) Filtration – occurs in the glomerulus, fluid portion of blood is forced into the glomerular capillaries the plasma proteins in blood are retained here. In this process the glomerulus capsule contains nitrogenous waste, ions, and much of the bloods water.
 * 2) Secretion – happens in the nephron tubule. As the fluid moves through the tubule secretion selectively removes substance still left in the plasma
 * 3) Reabsorption – also occurs in the tubule walls. It returns glucose, amino acids, essential ion and water to the body. 99% of reabsorbed into the blood