HW 11-13 Flashcards
The LD50 of a pathogen is defined as:
1)The number of pathogen cells introduced per host required to kill 50% of host organism
2)The length of time required for a pathogen to kill 50% of host organisms
3)The number of pathogen cells required to generate symptoms in 50% of host organisms
4)The probability that an infection with a particular pathogen will lead to death of the host.
The number of pathogen cells introduced per host required to kill 50% of host organism
Bacteroides
Very active in digesting complex polysaccharides
Staphylococcus
The most abundant genus in the skin microflora
Helicobacter
Causes gastric ulcers and cancer
Clostridium
Causes severe disease if parts of the microbiome are depleted
Methanobrevibacter
A rare Archaea in the microbiome
Siderophore
Iron acquisition by the pathogen
Capsule
Evasion of phagocytosis
Enterotoxin
Causes diarrhea
Exotoxin
Disrupts host cell function
The most abundant bacteria in the human skin microflora are Gram- _____cocci
positive
Inflammation of the membranes of the central nervous system is called:
meningitis
Which of the following is FALSE about the lymphatic system?
1)It delivers water to the extremities
2)It contains no erythrocytes
3)It contains T and B cells
4)It contains macrophages
5)It drains water from the extremities
It delivers water to the extremities
Which of the following is used by phagocytes to kill bacteria?
1)Antibiotics
2)Hydrogen peroxide
3)Apoptosis
4)Nucleases
5)Granzymes
Hydrogen Peroxide
B cell
Presents antigens to T cells
Th2 cell
Activates B cells to divide and differentiate
Tc
kills virus-infected host cells
Plasma cell
Produces antibodies
The enormous diversity of antibody-encoding genes is generated by the process of:
VDJ recombination
Macrophages use Toll-Like Receptor 4 to recognize ____ produced by bacterial cells.
LPS
Describe TWO methods the human immune system uses to avoid producing antibodies that cause an autoimmune response
T cells go through tolerance, so they cannot recognize self-antigens, and B cells go through tolerance, so they cannot recognize self-antigens. These two facts provide double protection against an autoimmune reaction.
Which disease is commonly spread by Direct Host-to-Host transmission?
1)Cholera
2)Cancer
3)AIDS
4)Lyme disease
5)Malaria
AIDS
Mobidity
The number of new disease cases in a population is a time period
Mortality
The number of new deaths in a population in a time period
Prevalence
The number of total, old and new, cases in a population in a time period
Endemic
A disease that is constantly present in a population over time
A large increase in disease cases produced by a contaminated water source is called a ____ epidemic
common-source
A living agent, such as a mosquito, that spreads an infectious disease is called a:
vector
A disease that passes from an animal population to humans is called a:
zoonosis
Describe how Immunity works.
What must be true about the population for this to occur?
How are vulnerable individuals in the group protected?
To obtain herd immunity, a large percentage of the population must be immune to a disease, either through natural immunity, prior infection, or vaccination. This prevents that infectious agent from spreading in the population, thus protecting the small number of individuals that are vulnerable.
