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Piggy G, Pikachu, Reeses, Tiny Group 1: Outline the role of skin and mucous in define pathogens, active v. passive

Outline: 1 min - apple (cut, food coloring, wrap) 10 or less - pwr point (~10 slides) 4 min - videos 2 min - demo (3 volunteers: 1 "vulnerable" in back, "mucus" in front of him w/ velcro mit, "skin" in front of him w/ something flat) 1 min - apple conclusion (2 min - transitions)

ALLISON: can you bring all the stuff for the apple demo?

Brainstorming- Dodgeball - velcro mit/something that bounces the ball off/tennis ball ninja fight demonstration of some sort acting something out (with or without volunteers) How Does Skin Protect Humans? Cut an apple in half. Cover one half of the apple with plastic food wrap and leave the other half uncovered. Using a dropper, release several drops of food coloring on each half of the apple.

Videos: [] anatomy of skin: []

[] (!!!!!!)


 * Pathogen:** An agent of disease. A disease producer. The term pathogen most commonly is used to refer to infectious organisms. These include [|bacteria] (such as [|staph]), [|viruses] (such as [|HIV]), and fungi (such as [|yeast]). Less commonly, pathogen refers to a noninfectious agent of disease such as a chemical. The term pathogen was devised about 1880 and was compounded from [|patho-] meaning disease + -gen indicating a producer. Hence, a disease producer.


 * mucous:** mucous membrane is a part of body defense just like our skin but it lines the inner surface of our body it protects the body against the acids production and ph changes in side our body since it is a thick layer it also act as shock absorber.

Active and Passive Immunity
Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response. Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen. A vaccine stimulates a primary response against the antigen without causing symptoms of the disease (see [|vaccination]). Artificially acquired passive immunity is a short-term immunization by the injection of antibodies, such as gamma globulin, that are not produced by the recipient's cells. Naturally acquired passive immunity occurs during pregnancy, in which certain antibodies are passed from the maternal into the fetal bloodstream. Immunologic tolerance for foreign antigens can be induced experimentally by creating conditions of high-zone tolerance, i.e., by injecting large amounts of a foreign antigen into the host organism, or low-zone tolerance, i.e., injecting small amounts of foreign antigen over long periods of time.

What are the Physical Components of the Skin’s Defense?
Our body’s first line of defense is nonspecific (doesn’t fight specific antigenic invaders), and includes structures, chemicals, and processes that work to prevent pathogens entering the body. These first line defenders include the skin and mucous membranes of the respiratory, digestive, urinary, and reproductive systems. Did you know your skin is comprised of two main layers? The epidermis is composed of multiple layers of tightly packed cells, which few pathogens can penetrate on their own. In addition to this structural barrier, the natural shedding of dead skin cells removes many attached microorganisms. Then there are other cells called epidermal dendritic cells that actively patrol the skin to phagocytize (engulf and digest) pathogens. The dermis is situated beneath the epidermis and contains protein fibers called collagen. Collagen is a tough fibrous protein which gives skin the strength and pliability to resist abrasions that could introduce microorganisms.
 * epidermis
 * dermis
 * //The Epidermis//**
 * //The Dermis//**

What are the Chemical Components of the Skin's Defense?
Secreted by the skin’s sweat glands, perspiration contains salt and enzymes. Few microbes can live in a highly saline environment, like that of the skin’s surface. The lysozymes in sweat are a type of enzyme that can destroy the cell walls of bacteria. Sebusm is secreted by skins sebaceous (oil) glands. The oil helps keep skin pliable and less likely to break or tear and also lowers the pH of the skin to a more acidic level that inhibits the growth of many types of bacteria.
 * //Perspiration//**
 * //Sebum//**

What about the Role of Mucous Membranes?
Mucous-secreting membranes line all of our body cavities that are open to the outside environment. Unlike the skin’s surface epidermal cells, the epithelial cells on the outermost layer of mucous membranes are living. But like epidermal cells, epithelial cells are tightly packed together, preventing entry of pathogens into the body. Epithelial cells are also continually shedding, the discarded cells carrying away any attached microorganisms. Come visit the science and nature forums and where we can talk about the mad skills of the human body!