Immune system

What does immune mean

Free off (unaffected by something)

What are the four distinct categories of invaders (immunogens) that immune system will attack

• Live organism (bacteria, fungi, parasite, worms)

• Chemical toxins (poison ivy)

• Foreign cells (wrong blood type)

• Abnormal self-cells (cancer cells)

Two core functions of immune system

• Prevent invaders from entering our body

• attack them if they get in

The outline notes that our body defenses protect us using what four categories of weaponry

• Barriers, proteins, cells, and body processes

What does innate mean how and does this system respond to threats

• It means you are born with it

• Provides an immediate, localized, general (non-specific) defense against foreign invaders

What specialized tough protein fills the dead cells of the outer skin barrier, and why cant we rely on skin alone

• keratin

• it creates a tremendous physical shield, but because microscopic invaders can be super tiny, even tiny cut and can breach and allow to enter

Where are mucous membranes located, and how do they work with cilia

They line all body openings lacking skin (eyes, nose, mouth, ears, vajayjay, anvs) and deep internal tracts. Sticky mucus traps the invaders, and microscopic hairs called cilia sweep them along to be destroyed or removed.

What are the chemical barriers that helps surface defenses

• acid on the skin and in the stomach, enzymes in saliva and intestines, and bactericidal chemicals in tears and urine

What unique memory tool to remember the innate internal defenses

2-2-2 two cells, two proteins, two body processes

What are macrophages, and what internal organelle do they use to destroy pathogens

Giant phagocytic white blood cells “big eaters” they swallow invaders via phagocytosis and use enzyme lysosome organelle to digest them.

What aggressive cells are called the “pit bulls” of the immune systems and what is the technical term for cell death they cause.

Natural killers (NK). They drill holes into unrecognized cells, injecting enzymes that causes Apoptosis (programmed cell suicide)

What are interferons, and how do they act as cellular martyrs

Non living antimicrobial proteins secreted by virus-infected cells right before they die. They travel to healthy neighboring cells and interfere with virus replication by telling them how to block viral entry.

What is the complement system, and how does it eliminate bacteria?

Non-living plasma that circulate in the blood. When activated, they form a ring on an invader’s membrane, drill a physical hole, and use osmosis to force surrounding water to rush inside until the cell bursts

Why is inflammation an effective internal defense process, and what four components does blood bring to the site?

It rushes massive blood flow to an injured/infected area. The blood delivers

• RBC for oxygen

• Plasma for glucose (oxygen + glucose = energy for cellular repair)

• Platelets for clotting

• WBC to fight

5 signs of inflammation and rule about ice

• Red

• Hot

• Swollen

• Pain

• Decrease in movement

ice should only be used on occasion to slow down rapid inflammation

What is fever, what chemical generates it, and where does it act

• Pyrexia

• A rise in body temp. Kills heat sensitive microbes and speeds up tissue repair/wbc activity. Fighting release pyrogens (fever-generators) → signals brains hypothalamus to raise thermostat

What are the critical temperature milestones for an adult fever

• 98.6 (37) normal

• 102 above - fever reducing med (tylenol)

• 104 - doctor

• 107 above - ER (hyperpyrexia) denatures body enzyme

What three distinct advantage does the adaptive immune system have over the innate system

• Attacks specific invaders

• Has markers (SWAT) specific

• attacks faster and has memory

• covers multiple body system at once

Where do B-cells originate, where do they mature, and what does maturing mean

• B cells originate in Bone marrow, and mature in bone marrow

• maturing meaning immunocompetent (capable and trained to do their specific job)

What are antibodies (immunoglobulins), and do they directly kill pathogens

Y-shaped proteins secreted by activated B-cells (plasma cells). They do not directly kill invaders, they bind to foreign antigens to paralyze, inactivate, or clump them together

What is Opsonization, and why is it useful

Process of coating and tagging an invader with antibodies so that circulating macrophages can easily find, target, and engulf them

What are the 5 major classes of antibodies

lg (MAJGE)

lgA

found in external body fluids like saliva and tears

lgE

explicitly responsible for driving allergic overreactions

How do memory b cells alter the immune response during a secondary exposure to the same invader

They remember the specific antigen, skipping the slow initial primary phase to launch an immediate, prolonged defense that produces up to 1000 times more antibodies. → concept forms of immunization/vaccination

Where do T-cells mature, and what type of environment are they best suited to protect?

Grows in bone marrow, mature in thymus gland. Provides cell-mediated immunity, meaning they are our best defense once an invader gets inside our host body cells (like viruses)

What do Cytotoxic T-cells do, and how do they cause a sore throat during a common cold?

• They are the executioners that terminate infections directly. They bind to infected host cells and force them into apoptosis. During a cold, you get a sore throat because your own Cytotoxic T-cells are destroying your infected throat tissue cells to wipe out the virus inside them.

Why is Helper T-cells the most important immune cells in your body

They act as generals. They do not kill, but when invader is spotted, they release chemical messengers called cytokines that command and call for help from every single defense branch (inflammation, complement, macrophages, B-cells, and Cytotoxic t-cells)

How does HIV virus cause AIDS, and what does an AIDS patients actually die from?

HIV explicitly invades and destroy T-cells. Without these generals to release cytokines, the rest of immune systems never receives the call to fight. Patients do not die from HIV itself; they die from simple common colds mutating into severe pneumonia, or rare cancers that a healthy immune system would easily destroy

What are regulatory T-cells and what is their job

They act as the managers that deliberately slow down or stop the adaptive immune response once the invading threat has been successfully destroyed.

What is the difference between Active immunity and Passive immunity?

Active: Your own body actively builds defenses and memory cells in response to an antigen exposure

Passive: You passively borrow antibodies from an outside source; your body makes no memory cells and the protection is temporary

Given an example of Active natural vs active artificial immunity

active natural: accidentally catching a live cold or flu virus from a classmate

active artificial: getting a vaccination/flu (injecting a safe weakened antigen to force body to make memory cells)

Give an example of passive natural vs passive artificial

Passive natural: A mother passing natural antibodies to her baby across the placenta or through breast milk

Passive artificial: a doctor injecting a patient with manufactured antibody medicines to combat an active infections.

What exact biological chain reaction causes a localized allergy?

The immune system overreacts to a harmless allergen (like pollen) and produces too many lgE antibodies. these lgE antibodies bind to mast cells and basophils, forcing them to dump a massive flood of histamine

What is anaphylactic shock, and how does it differ from a standard localized allergy

It is a life-threatening, a whole body systemic allergic reaction when an allergen directly enters the bloodstream (eg bee sting, venomous bite). Widespread histamine releases causes universal blood vessel dilation, leading to a critical drop in blood pressure (severe hypotension) along with suffocating airway constriction

What medical tool is used to reverse anaphylactic shock what hormone does it contain and what does it do

Epipen, delivers epinephrine (adrenaline). It force the body fight or flight which beats heart faster, constricts blood vessels to raise blood pressure back to normal and dilates the lung airways so the patient can breathe