MICROBIOLOGY FUNDAMENTALS: A CLINICAL
APPROACH, 2ND EDITION. CHAPTER 11
CAREFULLY ANALYSED QUESTIONS WITH
VERIFIED ANSWERS
The Human Host ANSWER >> The human body is in a state of dynamic equilibrium
with microorganisms
Healthy individuals have a peaceful coexistence with microbes and a lack of disease
Occasionally the balance tips in favor of microbes and disease results
1
,Infectious Disease ANSWER >> Disruption of a tissue or organism caused by microbes
or their products
Contact progresses to infection and ends in disease
Not all contacts lead to colonization
Not all colonization leads to infection
Not all infections lead to disease
Contamination without colonization and colonization without disease are the rules
Normal (resident) biota ANSWER >> Known as indigenous flora or normal flora
Include an array of bacteria, fungi, protozoa, viruses, and arthropods
Human Microbiome Project ANSWER >> Uses metagenomics
2
,Identifies genetic sequences to determine which microbes are inside and on humans,
even though they can't be cultured in the lab
Determines what the normal biota play in human health and disease
Acquiring Resident Biota ANSWER >> The human body has an endless variety of
microbial niches
Most areas of the body in contact with the outside environment harbor resident
microorganisms
Internal organs and tissue and their fluids are microbe-free
Majority of microbes that come in contact with the human body are destroyed by the
immune system before they are able to colonize
The microbes that remain have developed a complex relationship with the human host
in which they can survive and not be harmful to the host
Sites that harbor a known normal biota ANSWER >> Skin
3
, Mucous membranes
Respiratory tract
GI tract
Outer opening of urethra
External genitalia
Vagina
External ear canal
External eye (lids, conjunctiva)
Lungs
Bladder & urine
Breast milk
Amniotic fluid & fetus
Brain
Bloodstream
4
APPROACH, 2ND EDITION. CHAPTER 11
CAREFULLY ANALYSED QUESTIONS WITH
VERIFIED ANSWERS
The Human Host ANSWER >> The human body is in a state of dynamic equilibrium
with microorganisms
Healthy individuals have a peaceful coexistence with microbes and a lack of disease
Occasionally the balance tips in favor of microbes and disease results
1
,Infectious Disease ANSWER >> Disruption of a tissue or organism caused by microbes
or their products
Contact progresses to infection and ends in disease
Not all contacts lead to colonization
Not all colonization leads to infection
Not all infections lead to disease
Contamination without colonization and colonization without disease are the rules
Normal (resident) biota ANSWER >> Known as indigenous flora or normal flora
Include an array of bacteria, fungi, protozoa, viruses, and arthropods
Human Microbiome Project ANSWER >> Uses metagenomics
2
,Identifies genetic sequences to determine which microbes are inside and on humans,
even though they can't be cultured in the lab
Determines what the normal biota play in human health and disease
Acquiring Resident Biota ANSWER >> The human body has an endless variety of
microbial niches
Most areas of the body in contact with the outside environment harbor resident
microorganisms
Internal organs and tissue and their fluids are microbe-free
Majority of microbes that come in contact with the human body are destroyed by the
immune system before they are able to colonize
The microbes that remain have developed a complex relationship with the human host
in which they can survive and not be harmful to the host
Sites that harbor a known normal biota ANSWER >> Skin
3
, Mucous membranes
Respiratory tract
GI tract
Outer opening of urethra
External genitalia
Vagina
External ear canal
External eye (lids, conjunctiva)
Lungs
Bladder & urine
Breast milk
Amniotic fluid & fetus
Brain
Bloodstream
4
