2 Physical and Chemical Defenses Skin- Both a physical and chemical barrier. Sweat contains acids that kill many bacteria. Skin cells shed constantly and pathogens on those skin cells shed with them.Mucous Membranes- Openings such as mouth, eyes, and nose. Secrete liquid called mucus, which trap pathogens and washes them away. Also contains chemicals that attack pathogens.
3 Cilia- Tiny hair like projections. Line mucous membranes. Ex Cilia- Tiny hair like projections. Line mucous membranes. Ex. Breathing in dust.Saliva and tears- Contain chemicals and also wash away pathogensDigestive system- Chemicals such as acid, the motions of the digestive system, and excretion all help get rid of pathogens
4 Inflammation This is your bodies general response to injuries Phagocytes- White blood cells that leak out of cells when injury occursPhagocytes engulf and destroy pathogens while the area is inflamedPhagocytes also give off substances that promote healing.
5 The Immune SystemWhite blood cells called Lymphocytes carry out most of the immune system’s functionsImmunity is when the body is already equipped to destroy pathogens that enter the body
6 Lymphocytes Killer T cells- Destroy pathogen Helper T cells- Produce chemicals that stimulate other T cells and B cells to fight off infectionSuppressor T cells- turn off other immune system cells when an infection has been brought under control
7 B cells produce antibodies. Antibodies are proteins that attach to the surface of pathogens or to the toxins produced by pathogens.
8 The Lymphatic SystemA network of vessels that collect fluid from your tissues and return it to the blood stream. This fluid is called lymph fluid.Have hundreds of small stations called lymph nodesLymph nodes act as a sort of filterPhagocytes and lymphocytes are contained in the lymph node and attack pathogens
9 Passive and Active Immunity Passive: Immunity acquired by receiving antibodies from a source other then one’s own immune system. This is temporary and not life long.Ex. Babies receive antibodies from the mother’s milkActive: Results from having a disease or receiving a vaccine.
10 Common Infectious Diseases Bacterial DiseasesStrep Throat: Found usually in the nose and throat. Symptoms: Swollen lymph nodes, sore throat, head ache, and fever. Diagnosed by swabbing the throatLyme Disease: contracted when bitten by a tick. Symptoms: red rash at bite site, fevers, chills and body aches.
11 III. Bacterial Meningitis: Infection of the spinal cord and the fluid that surrounds the brain. Symptoms: high fever, headache, vomiting, and stiff neck. IV. Tuberculosis (TB): Transmitted when droplets of an infected persons cough or sneeze are inhaled. Symptoms: Fatigue, mild fever, and a constant cough. The disease may not show up for years after contraction.
12 Treating Bacterial Infections Antibiotics are used to treat bacterial infectionsAntibiotic resistance can happen when a person does not take all of their prescribed medicine.
13 Viral InfectionsCommon cold: Symptoms include sneezing, sore throat, coughing, chest congestion, head aches and muscle aches. Most last three to seven days. Colds spread when a person touches a contaminated object or inhales droplets from a sneeze or a cough.Influenza: Infection of the upper respiratory system. Symptoms: High fever, sore throat, headache, and a cough. Spread same as cold.
14 Pneumonia: People who have heart disease or are elderly may experience their flu turn into pneumonia.Hepatitis:Type A: Transmitted through human wastes or contaminated water.Type B: More severe then type A. Transmitted through blood or sexual contact.Type C: Transmitted through blood or sexual contact. Type C is the number one reason for liver transplants in the U.S
15 Treatment of Viral Infections In most cases there are no particular medicine that can cure a viral infection.Best treatments are : rest, a well-balanced diet, and plenty of fluids.There are also many medicines that treat viral symptomsThese medicines make a person feel better but do not rid the body of the virus.
16 When Should I See a Doctor? Extremely sore throat, earache, vomiting, diarrhea, or temperature of 101 F that lasts for more then two daysMucus from your nose or throat is thick and yellowDifficulty breathing, or severe pain anywhereA cut or scrape that does not heal as it shouldAn illness that lasts longer then usual
17 PreventionWash HandsDo not share items that transfer pathogens (towels, eating utensils, cups or hair brushes)Cook and store food properlyAvoid close contact with infected individualsStay home when not feeling wellLearn to manage stress in healthful waysSleep at least 8 hours a nightAvoid unhealthful substances. Ex: Drugs