Lecture 23

Question 1

List some (7) factors affecting the individual and general health that contribute towards defense mechanisms against disease

Answer 1

1. age
2. gender
3. mental state
4. living conditions
5. occupation
6. fatigue
7. nutrition

Question 2

Why are the very old more susceptible to disease?

Answer 2

they have underlying illnesses

they may not eat right or exercise enough

may smoke

have a decreased antibody production

Question 4

Name the (3) different types of genetic defense mechanisms

Answer 4

1. species immunity
2. racial immunity
3. individual immunity

Question 4

What is the ID50 for Salmonella typhimurium?

Answer 4

food poisoning need 100,000 bacilli

Question 5

Give some examples of the species immunity/barrier

Answer 5

• small pox- a human only disease
• typhoid- human only disease
• hand, foot, and mouth disease for humans VS. hoof and mouth disease for cows

Question 5

Give some examples of racial immunity

Answer 5

• TB- highest in native americans (due to poor nutrition)
• malaria- most common in black Africans

Question 6

What are residents and transients?

Answer 6

• 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

Question 7

why are the very young more susceptible to disease?

Answer 7

• 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

Question 7

What disease are firefighters exposed to?

Answer 7

Hepatitis C because it is transmitted through blood

Question 8

How are eyes considered a first line of defense?

Answer 8

• 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+)

Question 9

Why is the skin considered a first line of defense?

Answer 9

• it sloughs off regularly, taking the microorganisms with it
• skin is also acidic

Question 10

Why are females more susceptible to UTI infections?

Answer 10

Females have a shorter urethra than males

Question 12

Name some natural defenses people have developed against malaria

Answer 12

• 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

Question 13

How does the GI system act as a first line of defense against microbes?

Answer 13

• 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

Question 14

What is the ID50 for Salmonella typhi?

Answer 14

typhoid fever 1,000-10,000 bacilli

Question 15

What takes advantage of you when you’re tired?

Answer 15

• cold sores (herpes simplex 1)
• genital herpes (herpes simplex 2)
• mononucleosis

Question 16

What is your first line of defense against microorganisms?

Answer 16

natural barriers including:

1. skin
2. mucous membranes
3. GI system
4. eyes
5. genito-urinary system

Question 18

What is CCR5? How does it relate to delta 32?

Answer 18

• 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

Question 19

How do mucous membranes act as a first line of defense?

Answer 19

the mucous traps the organisms and the cillia slowly push it towards our GI tract

Question 20

Give examples of individual immunity

Answer 20

• athlete’s foot
• MS
• rheumatic fever