Everything You Wanted to Know About the Immune System

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Everything You Wanted to Know About the Immune
SystemAnd More!!!
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Keeping Pathogens OUT!!!

• Always exposed to pathogens!
• Body destroys most all of them
• Remember- some can be good!
• But many are bad news!

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1st Line of Defense

• 5 major barriers

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5 Barriers

• Tears- wash them away, chemicals that kill them
• Saliva- in your mouth
• Skin- protective barrier (can enter through cut,
  burn, or scrape)
• Mucus Membranes- tissues line nose, throat,
  mouth, eyes, openings (they trap pathogens)
• Stomach Acid- acid destroys it

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Immune System

• Immune System- combo of body defenses that are
  made up of cells, tissues, and organs that fight
  off pathogens.
• kicks in when these 5 barriers
• dont work
• 1. Non-Specific Response
• 2. Specific Response

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Non-Specific Response

• When pathogens enter the body, immune system
  ATTACKS!
• SAME no matter the pathogen
• Inflammatory Response- if pathogen gets past 5
  barriers (What are they??)
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• Phagosytes- special white blood cells that kill
  pathogens!
• How?
• - High blood pressure releases proteins that
  defend the body
• Interferons.- the proteins that stop the
  pathogen from reproducing and helps the cells
  fight infection.

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Phagocytes
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Non-Specific

• Inflammation- bodys response to injury or
  disease, resulting in a condition of swelling,
  pain, heat, and redness.
• Occurs in the blood and the tissues 
• -Fever- happens when the infection spreads
  through your body. Body heats up- tells your
  body to make more white blood cells so its
  harder for pathogens to reproduce (fight the
  disease harder)

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Specific Response

• The pathogen just got through 5 barriers and
  Non-Specific
• This defense tailored to fight a specific
  pathogen
• Immune system both fights and remembers the
  pathogen so it is more likely to fight it off
  right away if it ever enters your body again
• Lymphatic System the body uses this system to do
  its specific fighting

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Lymphatic System

• Secondary circulatory system that helps the body
  fight pathogens and maintain its fluid balance.
• This system circulates lymph, which has many
  lymphocytes and macrophages in them.
• Lymphocytes- Special white blood cells in lymph
• B Cells- formed in bone marrow (stop viruses from
  getting into cells to reproducing)
• T Cells- thymus gland (fight existing pathogens)
• NK Cells- Natural Killer Cell (attacks cancerous
  growths)
• Macrophages Phagocytes that help lymphocytes
  identify these invaders

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• These Lymphocytes are activated when these
  macrophages recognize the part of a pathogen
  known as an antigen.
• Antigen- substances (part of the pathogen) that
  send the immune system into action.
• Body reacts to these antigens by making
  Antibodies
• Antibodies- proteins connect to antigens, keeping
  them from harming the body. Makes the antigen so
  it cant reproduces

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Immunity

• Thats why we get vaccinated- so we can develop
  antibodies. 
• Immunity- your bodys ability to resist the
  pathogens that cause a particular disease
• Virus mutes and changes, therefore the previous
  vaccines are ineffective.