A fever is a neurological response that unwraps proteins and increases metabolism. It unravels pathogens too to make them easier to kill. However temps too high for too long can be irriversible and cause more damage than good
What kind of surface barriers do we have?
Protective chemicals to inhibit or destroy microorganisms
Skin acidity- keratin
-lipids in sebum and dermcidin in sweat
-HCl and protein digestion enzymes in our gut
-Lysozyme in saliva and lacrimal fluid
Name two kinds of macrophages
Aleolar- free macrophages wander through tissues spaces
Kupffer cells (liver) and microglia (brain)- fixed macrophages that are perminate residents
How does phagocytosis operate?
-phagocyte forms around the microbe
-lysosomes fuse with phagocytic vesicle
-microbe is broken down and deposited out of the cell in exocytosis
What are natural killer cells?
-Large granular lymphocytes
-targets cells that lack self receptors
-induce apoptosis in cancer and virus infected cells
-secrete potent chemicals that enhance the -imflammatory response
Describe what happens during the healing process.
l-eukocytosis- chemical response to increase WBC
-diapedesis- move from capillary to tissues -chemotaxis
-pus from macrophages
Primary mechanisms of defense
1. Phagocytosis- digest viruses by macrophages
2. memory cell activation- recall pathogens we have had previously
3. antibody mobilization- neutrilize and stop pathogen from hurting us
What is margination?
rolling along membrane to find signal to leave capillary
What do interferons do?
-activate macrophages and mobilize NK.
-virus enters cell
-interferon genes get switched on
-cell produces interferon molecules
-antiviral proteins block viral reproduction
-interferon binding stimulates cell to turn on geses for antiviral proteins
-cell dies after interferon
What are complements?
-about 20 blood proteins that circulate in an inactive form
-amplifies all aspects of the inflammatory response- helps create chemical trail and clumps pathogens
-kills bacteria and certain cell types by cell -lysis
-enhances both non specific and specific defenses
How exactly does a fever start?
leukocytes and macrophages secrete pyrogens which reset the bodies thermostat upwards
Why is a fever dangerous?
It unwinds proteins so we can access protein molecules faster but unprotected and unwound the proteins can fracture or break.
What two organs can sequester Fe/Zn during a fever?
spleen and liver
Specific, systemic, has memory
1. Humoral (antibody-mediated) immunity B cells Dont attack
2. Cellular (cell-mediated) immunity T cells attack
Where do they lymphocytes originate and mature?
-Originate in red bone marrow
-b cells mature in red bone marrow
-t cells mature in the thymus
-Immature cells live in lymph nodes have not yet come in contact with viruses yet
When they mature, cells have...
Immunocompetence- they are able to recognize and bind to a specific antigen
self-tolerance- unresponsive to self antigens
What are antigens?
-markers of things that exist, belong or dont belong
-bacteria and virus look for specific cells to infect by locating their antigens and our cells attack viruses and bacteria by identifying their antigens
What are antibodies?
-have and affinity for antigens
-bind and identify
-if antigens don't belong- neutralization, agglutination, and precipitation
What is positive selection?
-T cells must recognize self major histocompatibility proteins
-matching is good/ no match = cell death
What is negative selection?
-T cells must not recognize self antigens- if it recognizes its own cell apoptosis occurs-if it doesnt match up then it goes to maturation
Explain B cells
-bind with antigens it identifies
-replicates to plasma cells and memory cells
-antibodies are made from plasma cells
-2nd response is greater and faster
Immunological memory- Primary immune response
-Occurs in first exposure to a specific antigen
-lag period is 3-6 days
-peak levels of plasma antibody are reached in 10 days
-antibody levels then decline
Immunological memory- secondary immune response
-Occurs on re-exposure to the same antigen
-sensitized memory cells respond within hours
-antibody levels peak in two to three days -at much higher levels
-antibodies bind with greater affinity
-antibody level can remain high for two weeks to two months
Name four ways we can acquire immunity.
Active- infection- contact with pathogen
Passive- antibodies pass from mother to fetus
Passive- injection of immune serum -antibiotics
Basic antibody structure
-IgM- fixes and activates complement
-IgA- helps prevent entry of pathogen
-IgD- Function as a B cell receptor
-IgG- fetus development
-IgE- causes mast cells and basophils to release histamine
Functions of Antibodies
-leads to inflammation or phagocytosis
-fixes complement- leads to cell lysis or inflammation
Complement proteins do what three things
-utilized to enhance function
-used as weapon
Name two types of T Cells
CD8 and CD4
-activated cytotoxic cells
-activated helper cells
-recruits macrophages and NK cells to kill specific cells
-cytokin can initiate b cell pathway and b cells can activate helper t cells
Name four varieties of Organ Transplants
Autographs: one body site to another in the same person
Isografts: between identical twins
allografts: between human to human
xenografts: another animal species to human
Prevention of rejection
-depends on tissue similarity
-cartilage and cornea and ligament- 0 blood flow
-more blood flow= higher chance of rejection
-treated with immunosuppressive therapy, corticosteroid- suppress inflammation, antiproliferative
What does the conducting zone do?
passage of air. Moisten and warm air, filter, resonation chamber, and smell receptors.
Why do we have three concha and meatus?
to increase surface area.
Functions of Nasal Mucosa and Conchae
-During inhalation, the conchae and nasal mucosa- filter, heat, and moisten air
-During exhalation these structures
-reclaim heat and moisture
Name 3 Larynx functions
1. Open airway
2. route food and air
What is the Valsalva's Maneuver?
Vocal cords can prevent air passage- intermittent release of air-
-opens and closes- tense cords-
-fast vibration and high pitch
What two layers line the lumen of the trachea?
1. pseudostratified ciliated columnar epithelium
2. seromuccous glands in submucosa
How many segments are in the lung?
10 segments in the right lung9 segments in the left lung
What is the point of avleolar pores?
to relieve pressure in the lungs
Describe the alveoli.
-small sacs of air
-300 million alveoli
-elastic fiber contracts
- capillaries surround each aveoli
What are two cell types in the Alveoli?
Type I. squamous epithelium each alevolar is only made up of simple squamous ethithelium for gas exchange
Type II. Surfactant secreating cell surfactant- weaken surface tension between water molecules
What role does water play in alveoli?
-water resists helps in exhange
-water tension puts resistance in alveolus
How do the parasympathetic and sympathetic systems affect the lungs?
-Parasympathetic fibers constrict air tubes
-Sympathetic fibers dilate air tubes
Explain the pressure residing in the chest cavity.
-The visceral tissue lines the organ.
-The parietal tissue lines the ribs.
-The serous fluid in the pleural cavity is in between.
Explain how the lungs get blood to function.
-Systemic circulation (high pressure, low volume)
-fed by bronchial arteries/ capillaries
-enter lungs at hilum
-bronchial veins anastomose with pulmonary veins
What is the Pleurae?
-A thin, double-layered serosa
-parietal pleura on thoracic wal and superior face of diaphragm
- Visceral pleura on external lung surface
-pleural fluid fills the pleural cavity and provides lubrication and surface tension
Diaphragm contracts, interxostals contract lifting the rib cage, moves sternum and rib cage
passive, intercostals and diaphragm relax, no muscles
Explain what Intrapleural Pressure is
-Negatice interpleural pressure is caused by opposing forces.
- Two inward forces promote lung collapse- elastic recoil of lungs decreases lung size and surface tension of alveolar fluid reduces alveolar size
-one outward force tends to enlarge the lungs, elasticity of the chest wall pulls the thorax outward
Which pressure should always be higher?
Intrapleural pressure should always be less than intrapulmonary pressure.
Intrapulmonary (inside the lung) should be higher
higher pressure = lower volume
lungs at rest = 1 atm
when volume increases= pressure drops
move from high pressure to low pressure
Explain the relationship between transpulmonary pressure and intrapulmonary pressure.
The difference stays relatively the same throughout breathing.
Explain the four individual volumes the lung contains.
1. Tidal volume- vol of air moving in and out normally
2. inspiratory volume- amount of air that can be forcibly inhaled
3. Expiratory volume- amount of air that can be forcibly exhaled
4. Residual volume- remains even after strenous expiration