RAT 13 Flashcards
what are the three main ways that the immune system can malfunction?
- can overreact and damage tissues, results in hypersensitivity disorder
- one or more components may fail, which is an immunodeficiency
- may treat self antigens as foreign and attack the body’s disorder own tissues, which is an autoimmune disorder
what is the common term for the most common type of hypersensitivity?
allergies
what is the term for a life-threating hypersensitivity reaction?
anaphylactic shock
what occurs during anaphylactic shock?
- serve spasm of the smooth muscle in the larynx
- systemic vasodilation, which causes blood pressure to drop and decreases blood flow to all organs including the brain
- increased capillary permeability in all the body’s capillaries, which further lowers blood pressure and causes the body wide swelling and massive loss of fluid to the lungs
what medication helps to combat anaphylactic shock?
epinephrine
how does epinephrine help with the responses of anaphylactic shock?
causes relaxation of the smooth muscle of the airways and systemic vasoconstriction
what are the two main types of immunodeficiency disorders?
- primary immunodeficiencies
- secondary immunodeficiencies
describe primary immunodeficiencies.
- genetic or developmental in nature
- may effect innate or adaptive immunity
- serve combined immunodeficiency (SCID)
- leukopenia
describe secondary immunodeficiencies
- acquired through infection, trauma, cancer, or certain medications
- acquired immunodeficiency syndrome (AIDS)
- HIV-1
signs and symptoms of AIDs are largely due to the destruction of which cell type?
helper T cells
how does destruction of helper T cells (due to AIDs) impact the performance of the immune system?
causes the entire adaptive immunity response to fail, leading to recurrent infections
what is an autoantibody?
antibodies that bind to self-antigens
list four examples of autoimmune disorders
- release of self antigens not previously encountered by T cells
- foreign antigens mimic self antigens
- cells may inappropriately express class II MHC molecules
- certain pathogens nonspecifically activate B cells
what is gas transport?
the movement of gases in the blood
what percentage of oxygen in the blood travels dissolved in the plasma?
1.5%
how is most oxygen transported in the blood?
on the protein hemoglobin (Hb)
what is a loading reaction?
converts hemoglobin from deoxyhemoglobin to oxyhemoglobin
where do loading reactions take place?
pulmonary capillaries
what is an unloading reaction?
hemoglobin releases oxygen to the tissue cells
where do unloading reactions take place?
systemic capillaries
when is hemoglobin said to be partially saturated?
hemoglobin with 1-3 oxygen molecules
when is hemoglobin said to be fully saturated?
hemoglobin with 4 oxygen molecules
why is it important that the oxygen delivery to tissues match the metabolic demand?
if hemoglobin does not provide adequate oxygen, the cells will not be able to produce adequate ATP; too much will cause toxicity and cellular damage
what is the percent saturation of Hb?
the percentage of Hb bound to oxygen
if a hemoglobin has 4 oxygen molecules bound, what is its percent oxygen saturation? 3? 2? 1?
4 - 100%
3 - 75%
2 - 50%
1 - 25%
how saturated is hemoglobin when it leaves the lungs?
97-100%
How saturated is hemoglobin when it leaves the tissues?
~ 75%
how much carbon dioxide is transported in the blood dissolved in plasma?
7-10%
how much carbon dioxide is transported bound to hemoglobin? where does it bind?
- ~ 20%
- hemoglobin’s polypeptide chains
how is most carbon dioxide transported in the blood?
as bicarbonate ions
what is the name of the enzyme found in RBCs?
carbonic anhydrase (CA)
what two irons are exchanged during the chloride shift?
- bicarbonate ions
- chloride ions
why does the pH change very little when hydrogen ions are added?
because the hydrogen ions bind with buffers such as bicarbonate ions to form carbonic acid
why does removing hydrogen ions from the blood not have a large impact on the blood pH?
because the hydrogen is just released from the carbonic acid it’s stored on
explain why a buffer system helps to maintain a relatively stable pH in the body?
- carbonic acid works as the buffer
- too many hydrogen ions, then they bind to bicarbonate ions to form carbonic acid (so they are no longer free)
- when there are too few hydrogen ions, carbonic acid releases hydrogen ions
what is the major determinant of the amount of carbonic acid in the blood?
CO2
what two factors are the main determinants for Pco2?
- hyperventilation
- hypoventilation
how does hyperventilation impact Pco2?
Pco2 decreases
how does hyperventilation impact pH?
pH increases
how does hypoventilation impact Pco2?
Pco2 increases
how does hypoventilation impact pH?
pH decreases
explain how changes in breathing rate are a quick way to change blood pH?
breathing rate changes effect the levels of CO2 in blood which directly affects the pH of the blood as more or less hydrogen ions will be present
what are the two general categories of lung disease?
- restrictive
- obstructive
what characterizes restrictive lung diseases?
- decrease pulmonary compliance
- reduce effectiveness of inspiration
what characterizes obstructive lung diseases?
- increase airway resistance
- decrease efficiency of expiration
what are COPD’s?
- chronic obstructive pulmonary disorder
- persistent airway obstruction that is not fully reversible
list two common COPD’s.
- emphysema
- chronic bronchitis
what is the most common cause of COPD’s?
cigarette smoking
what happens when a person with asthma is exposed to a trigger?
- bronchoconstriction
- inflammation
- increased production of excessively thick mucus
- all which increases airway resistance
what is the number one cancer killer?
lung cancer
what is the number one risk factor for lung cancer?
cigarette smoking
