Lecture 23 Flashcards
Defense mechanisms against disease part 1
List some (7) factors affecting the individual and general health that contribute towards defense mechanisms against disease
- age
- gender
- mental state
- living conditions
- occupation
- fatigue
- nutrition
Why are the very old more susceptible to disease?
they have underlying illnesses
they may not eat right or exercise enough
may smoke
have a decreased antibody production
Name the (3) different types of genetic defense mechanisms
- species immunity
- racial immunity
- individual immunity
What is the ID50 for Salmonella typhimurium?
food poisoning need 100,000 bacilli
Give some examples of the species immunity/barrier
- small pox- a human only disease
- typhoid- human only disease
- hand, foot, and mouth disease for humans VS. hoof and mouth disease for cows
Give some examples of racial immunity
- TB- highest in native americans (due to poor nutrition)
- malaria- most common in black Africans
What are residents and transients?
- residents are organisms that are normal flora on your skin, they take up space and secrete fatty acids
- Transients are not normally found on skin
why are the very young more susceptible to disease?
- the very young have decreased antibody production and low levels of complement (proteins in the blood that help identify foreigners)
- because of their lack of exposure
What disease are firefighters exposed to?
Hepatitis C because it is transmitted through blood
How are eyes considered a first line of defense?
- tears mechanically flush away organisms
- tears contain immunoglobulin A, an antibody that helps to protect against recurring infection
- tears also contain lysozymes (more effective on G+)
Why is the skin considered a first line of defense?
- it sloughs off regularly, taking the microorganisms with it
- skin is also acidic
Why are females more susceptible to UTI infections?
Females have a shorter urethra than males
Name some natural defenses people have developed against malaria
- sickle cell anemia- can’t develop in these cells
- lack of a duffy factor- lack of the factor means malaria can’t get into the red blood cell and develop
How does the GI system act as a first line of defense against microbes?
- the stomach has a pH of 1-3 which inhibits the growth of most microbes
- the small intestine produces bile which inhibits most G+ bacteria
- The large intestine poops out the bacteria in it
What is the ID50 for Salmonella typhi?
typhoid fever 1,000-10,000 bacilli
What takes advantage of you when you’re tired?
- cold sores (herpes simplex 1)
- genital herpes (herpes simplex 2)
- mononucleosis
What is your first line of defense against microorganisms?
natural barriers including:
- skin
- mucous membranes
- GI system
- eyes
- genito-urinary system
What is CCR5? How does it relate to delta 32?
- a co-receptor to AIDS which the virus binds to
- a delta 32 mutation breaks this and the AIDS virus can’t get into the cell
- most common in white Europeans
How do mucous membranes act as a first line of defense?
the mucous traps the organisms and the cillia slowly push it towards our GI tract
Give examples of individual immunity
- athlete’s foot
- MS
- rheumatic fever
