Unit 2 Compendium 1- Maintenance of the Human Body

Table of Contents

I. Cardiovascular System: Heart and Blood Vessels

A. Overview of the Cardiovascular System

B. The Types of Blood Vessels

C. The Heart is a Double Pump

D. Features of the Cardiovascular System

E. Two Cardiovascular Pathways

F. Exchange at the Capillaries

G. Cardiovascular Disorders

II. Cardiovascular System: Blood

A. Blood: An Overview

B. Red Blood Cells and Transport of Oxygen

C. White Blood Cells and Defense Against Disease

D. Platelets and Blood Clotting

E. Blood Typing and Transfusions

F. Homeostasis

III. Lymphatic System and Immunity

A. Microbes and Pathogens

B. The Lymphatic System

C. Nonspecific Defenses

D. Specific Defenses

E. Acquired Immunity

F. Hypersensitivity Reactions

IV. AIDS Supplement

A. Origin and Prevalence of HIV

B. Phases of an HIV Infection

C. HIV Structure and Life Cycle







I. Cardiovascular System: Heart and Blood Vessels

A. Overview of the Cardiovascular System

1. Contractions of the heart generates blood pressure, which moves blood through blood vessels.

2. Blood vessels transport blood, which moves from the heart into arteries, capillaries, and veins, before returning to the heart.

3. Exchanges at the capillaries (the smallest of the blood vessels) refreshes blood and then tissue fluid, sometimes called interstitial fluid.

4. The heart and blood vessels regulate blood flow, according to the needs of the body.

B. The Types of Blood Vessels

1. Arteries: blood flows from the heart to the body.

2. Capillaries: moves blood from the Arteries to the Veins.

3. Veins: blood flows from the body to the heart.

C. The Heart is a Double Pump

1. The heart has a right and left side, each having an Atrium and a Ventricle. Valves keep the blood moving in the correct direction.

2. Passage of blood through the heart.

a. The right atrium recieves O2 poor blood from the body, and the right ventricle pumps it into the lungs.

b. The left atrium recieves the O2 rich blood from the lungs, and the left ventricle pumps it to the rest of the body.

3. The heart beat is controlled.

a. The SA node initiates the heartbeat by causing the atria to contract, then the AV node conveys the stimulus to the ventricles, causing them to contract.

b. "Lub-Dub" is caused from the closing of the atrioventricular valves, followed by the closing of the semilunar valves.

D. Features of the Cardiovascular System.

1.Pulse- rythmic expansion and recoil of an atrial wall; felt at radial or carotid artery.

2. Blood Pressure- pressure of blood against the wall of a blood vessel.

a. Systolic pressure- Arterial blood pressure during the systolic phase of the cardiac cycle; ejection of blood from the heart.

b. Diastolic pressure- Arterial blood pressure during the diastolic phase of the cardiac cycle; relaxation of the heart ventricles.

E. Two Cardiovascular Pathways.

1. Pulmonary Circuit: Exchange of Gases- O2 poor blood leaves the heart through the pulmonary artery, exchanges CO2 for O2, and then travels back to the heart through the pulmonary vein.

2. Systemic Circuit: Exchanges with Tissue Fluid- 60,000 miles of veins and arteries.

a. Tracing the path of blood- Left Ventricle-> Aorta-> Common Iliac Artery-> Femoral Artery-> Lower Leg Capillaries-> Femoral Vein-> Common Iliac Vein-> Inferior Vena Cava-> Right Atrium.

b. Coronary Arteries- supply blood to the wall of the heart; connected to the Aorta.

Hepatic Portal Vein- takes blood from the capillary bed of the digestive tract to a capillary bed in the liver.

F. Exchange at the Capillaries.

1. Water, oxygen, amino acids, and glucose leave the capillary when there is more blood pressure and less osmotic pressure (on the artery side).

2. Carbon dioxide, wastes, and water enter the capillary when there is less blood pressure and more osmotic pressure (on the vein side).

G. Cardiovascular Disorders

1. Disorders of the blood vessels.

a. Aneurysm, High Blood Pressure (Hypertension), Low Blood Pressure (Hypotension), Atherosclerosis, Thrombus, Embolus, Thromboembolism, Plaque, Stroke, Heart Attack, Angina Pectoris, Blood Clots.

b. Treating Artery Disorders- Coronary Bypass Operation, dissolve blood clots using t-PA or a blood thinner, Angioplasty, Stents.

2.Disorders of the Heart.

a. Bicuspid or Tricuspid regurgitation, heart failure, Atrium Fibrilation (A-fib), Ventricular Fibrilation (V-fib).

b. Treatment of Heart Disorders- Heart transplant, artificial valves, pacemaker, artificial heart.

II. Cardiovascular System: Blood

A. Blood: An Overview

1. Functions- primary transport for O2 and CO2, defends the body against invasion by pathogens, and helps regulate body temperature through it'd pH.

2. Composition of Blood.

a. Formed Elements- Red blood cells, white blood cells, and platelets.

b. Plasma- plasma proteins, osmotic pressure, albumins, globulins, and fibrinogen.

B. Red Blood Cells and Transport of Oxygen.

1. Blood carries O2 through Hemoglobin (makes red blood cells red); The globin portion of the hemoglobin is a protein that contains 4 highly folded polypeptide chains, while the heme part of hemoglobin is an iron-containing group in the center of each polypeptide chain (iron accepts the O2 in the lungs and lets go of it in the tissue).

2. Blood transports CO2 through plasma- 7% is dissolved in the plasma, 25% is transported by the globin in the blood cell, and the left over 68% is transported as bicarbonate ions (HCO3-) in the plasma.

3. Red Blood Cells are produced in Bone Marrow.

a. Blood Doping- delivers O2 more efficiently and reduces fatigue- A low O2 blood level makes the kidneys increase production of erythropoietin, which makes the stem cells increase red blood cell production. Increase in RBC production makes the O2 level normal again.

4. Red blood cell disorders.

a. Anemia (low iron), Hemolysis (rupturing RBCs), Sickle-Cell Disease.

C. White Blood Cell and Defense Against Disease.

1. Types of WBCs: Granular and Agranular Leukocytes.

a. Granular Leukocytes- neutrophils, eosiniphils, and basophils. Neutrophils are abundant and respond to infections first. They phagocytize pathogens.

b. Agranular Leukocytes- monocytes and lymphocytes. Monocytes are the largest WBC and can become macrophages the phagocytize pathogens and cellular debris. Lymphocytes (B and T cells) are responsible for specific immunity.

D. Platelets and Blood Clotting.

1. When a blood vessel is puctured, platelets congregate and form a plug. Then platelets and damaged tissue cells release prothrombin activator, which initiates a cascade of enzymatic reactions (prothrombin to thrombin, and fibrinogen to fibrin threads). Finally, fibrin threads form and trap red blood cells.

2. Disorders related to blood clotting.

a. Thrombocytopenia (low platelet count), Thromboembolism (blood clot), Hemophilia (lack of clotting factor).

E. Blood Typing and Transfusions.

1. ABO blood groups

a. Type A blood- have type A surface antigens, and anti- B antibodies in the plasma.

b. Type B blood- have type B surface antigens, and anti- A antibodies in the plasma.

c. Type AB blood- have type A and type B surface antigens, and no anti- A or anti- B antibodies.

d. Type O blood- has no surface antigens, and both anti-A and anti-B antibodies in the plasma.

2. Blood compatability for transfusions.

a. Blood compatability is very important when transfusions are done. Blood- type matching must be done before a blood transfusion is performed to observe whether agglutination will occur between the donor and recipients blood.

3. Rh blood groups.

a. the Rh factor determines the positive or negative in blood type.

b. In a pregnancy where the child is Rh+ and the mother is Rh-, the Rh+ RBCs leak across the placenta into the mother's blood stream, where she forms anti- Rh antibodies. The antibodies then cross the placenta into the child and attack it's RBCs, causing Hemolytic disease of the newborn (HDN), which can lead to brain damage, mental retardation, or death.

F. Homeostasis- Maintenance of normal internal conditions in a cell or an organism by means of self-regulating mechanisms.

1. What each system does:

a. Cardiovascular System- blood vessels transport O2 and nutrients to the cells of all organs and transports wastes away from them.

b. Nervous System- nerves help regulate the contraction of the heart and the contraction/ dilation of blood vessels.

c. Endocrine System- blood vessels transport hormones from glands to their target organ.

d. Respiratory system- blood vessels transport gases to and from the lungs.

e. Digestive system- blood vessels deliver nutrients from the digestive tract, which provides the molecules needed for plasma protein formation and blood cell formation, through the blood.

f. Urinary system- kidneys excrete wastes, through the blood vessels, and help regulate the water- salt balance necessary to maintain blood volume and pressure and help regulate the acid- base balance of the blood.

g. Lymphatic system- helps maintain blood volume by collecting excess tissue fluid and returning it via lymphatic vessels to the cardiovascular veins.

h. Muscular system- muscles contract to keep blood moving through the heart and blood vessels, particularly veins.

i. Skeletal system- the rib cage protects the heart, red bone marrow produces blood cells, and bones store Ca2+ for blood clotting.

III. Lymphatic System and Immunity

A. Microbes and Pathogens.

1. Bacteria- single celled prokaryotes that don't have a nucleus.

a. Shapes of bacteria: Bacillus (rod), Coccus (spherical), and Spirillum (curved).

2. Viruses- acellular (not composed of cells), obligate parasites that do not live independently.

a. Viruses cause: colds, flu, measles, chicken pox, polio, rabies, AIDS,genetal warts, herpes.

3. Prions- proteinaceous infectious particles, cause a group of degenerative diseases of the nervous system.

a. Prions cause: Creutzfeldt- Jakob disease (CJD) in humans, Scrapie in sheep, and Bovine Spongiform Encephalopathy (Mad Cow Disease).

B. The Lymphatic System.

1. The Primary Lymphatic Organs.

a. Red Bone Marrow- produces all types of blood cells.

b. Thymus Gland- lymphatic tissue where T lymphocytes mature.

2. Secondard Lymphatic Organs.

a. Spleen- filters the blood.

b. Lymph Nodes- cleanse lymph and alert the immune system of pathogens.

c. Lymph Nodules- concentrations of lymph tissue.

d. Tonsils- same function as lymph nodes, but are the first to encounter pathogens and antigens, by way of the nose and mouth.

e. Peyer's patches- encounter pathogens by way of the intestinal tract.

C. Nonspecific Defenses

1. Immunity- the ability to combat diseases and cancer, includes lines of defense.

a. Barriers to entry.

b. The inflammatory reaction, which involves the phagocytic neutrophils and macrophages.

c. Protective proteins.

D. Specific Defenses

1. B cells and Antibody- Mediated Immunity

a. After activation, the B cells combine with a specific antigen, then undergo clonal selection, which produces plasma cells and memory B cells.

b. Plasma cells secrete antibodies and undergo apoptosis (the process of programmed cell death); Plasma cells are responsible for antibody- mediated immunity.

c. Memory B cells stay in the body to produce antibodies if the same antigen enters the body at a later date.

2. T cells and Cell- Mediated Immunity.

a. T cells recognize an antigen if it is presented by a macrophage with an HLA (Human Leukocyte Antigen).

b. Activated T cells undergo clonal expansion until the illness has been stemmed. Most undergo apoptosis, the rest stay as memory T cells.

c. Two main types of T cells: Cytotoxic (kill virus- infected cells on contact), and Helper (produce cytokines and stimulate other immune cells).

E. Aquired Immunity

1. Active Immunity

a. Immunizations, or Vaccines, are substances that contain an antigen to which the immune system responds.

2. Passive Immunity

a. Gamma Globulin Injection- serum that contains antibodies.

b. Cytokines- sinaling molecules produced by T lymphocytes, macrophages, and other cells, that regulate while blood cell formaton and/ or function.

F. Hypersensitivity Reactions

1. Allergies- Hypersensitivity to substances, such as pollen, food, or animal hair, that ordinarily would not harm the body.

a. Anaphylactic shock- an immediate and life threatening allergic response that occurs because the allergen, such as a bee sting or penicillin shot, has entered the bloodstream, and requires immediate medical attention.

2. Tissue Rejection- recipient's immune system recognizes that the transplanted tissue is not its own, and rejects the transplant.

3. Disorders of the Immune System

a. Auto-immune disease, myasthenia gravis, multiple sclerosis (MS), systemic lupus erythematosus (SLE), rheumatoid arthritis, AIDS, and severe combined immunodeficiency disease (SCID).

IV. AIDS Supplement

A. Origin and Prevalence of HIV

1. Pandemic- the disease is prevalent in the entire human population around the world.

a. Sub-Saharan Africa (24.5 million infected) and Asia (8.3 million)

b. Latin America (1.6 million) and the Caribbean (330,000)

c. North America (1.3 million), Europe and Central Asia (3.5 million)

d. North Africa and the Middle East (440,000)

e. Oceania (78,000)

B. Phases of an HIV Infection

1. Category A: Acute Phase

a. no apparent symptoms, highly infectious, and a CD4 T cell count never below 500 cells per mm³ of blood.

b. An HIV antibody test usually comes up negative because it usually takes about 25 days for detectable levels of HIV antibodies in body fluid.

2. Category B: Chronic Phase

a. CD4 count between 499 and 200 cells per mm³, and one or more symptoms related to an impaired immune system.

1. Yeast infection of the mouth or vagina, cervical dysplasia, prolonged diarrhea, hairy leukoplakia, shingles, swollen lymph nodes, unexplained persistant or recurrent fevers, fatigue, and/or cough.

3. Category C: AIDS

a. CD4 cell count below 200 cells per mm³, or has one or more of the 25 AIDS defining illnesses.

b. Some opportunistic infections:

1. Pneumocystis Jiroveci Pneumonia- a fungal infection of the lungs.

2. Mycobacterium Tuberculosis- a bacterial infection usually of lymph nodes or lungs but may be spread to other organs.

3. Toxoplasmic Encephalitis- a protozoan parasistic infection, often seen in the brain.

4. Kaposi's Sarcoma- an unusual cancer of the blood vessels, which gives rise to reddish purple, coin- sized spots and lesions on the skin.

5. Invasive Cervical Cancer- a cancer of the cervix, which spreads to nearby tissues.

C. HIV Structure and Life Cycle

1.HIV is made up of: two single strands of RNA, various proteins, an envelope that it gets from the host cell, and three protective protein coats (nucleocapsid, capsid, and matrix).

2. Three important enzymes within the matrix.

a. Reverse Transcriptase- catalyzes reverse transcription, which is the conversion of the viral RNA to viral DNA.

b. Integrase- catalyzes the integration of viral DNA into the DNA of the host cell.

c. Protease- catalyzes the breakdown of the newly synthesized viral polypeptides into functional viral proteins.

3. HIV Life Cycle

a. Attachment, fusion, entry, reverse transcription, integration, biosynthesis and cleavage, assembly, and budding.

4. Transmission and Prevention of HIV

a. Transmission

a1. Sexual contact (vaginal, rectal, or oral), needle- sharing with intravenous drugs, genetic passdown, and, very rarely, from a blood or clotting factor transfusion.

a2. Highest concentration of HIV is in blood, semen, vaginal fluid, and breast milk.

5. HIV Testing and Treatment

a. HIV tests do not test for HIV, they test for the presence of HIV antibodies.

a1. Antibodies do not show until 2 weeks to 6 months after infection occurs, and test results can take weeks.

b. Drug Therapy

b1. There is no cure for AIDS, but the Highly Active Antiretrovirus Therapy (HAART) will usually slow down the progression of the virus, giving the patient extra years of life. Hoever, the patient must stay on a regimen or the virus will become drug resistant.

c. Vaccines

c1. In 2006, 27 preventative vacines were used in human trials, but the results will not be in until 2010.