Microbiology Chapter 10
The most common organisms within the indigenous microflora of the mouth are various species of ________
(alpha)-hemolytic streptococci
Most frequent causes of urethral infections include _____
Chlamydia trachomatis, Neisseria gonorrhoea, and mycoplasmas.
The systematic study of the interrelationships that exist between organisms and the environment
Ecology
Includes all the microbes (bacteria, fungi, protozoa, and viruses) that reside on and within a person
Indigenous microflora (normal flora)
Defined as two dissimilar organisms living together in a close association
Symbiosis
_____ take up temporary residence on and within humans.
Transient microflora
True or False A change in conditions can cause one type of symbiotic relationship to shift to another type.
True
True or False As many as 100 trillion microorganisms could live on and in us at a time.
True
True or False Biofilms are very resistant to antibiotics and disinfectants.
True
True or False Blood, lymph, spinal fluid, and most internal tissues are normally free or microorganism.
True
True or False Destruction of resident microflora disturbs the delicate balance between host and microorganisms.
True
True or False Humans derive benefits from their indigenous microflora.
True
True or False Kidney, ureters, and urinary bladder are usually sterile.
True
True or False Lower respiratory tract is usually free of microbes.
True
True or False Many organisms in the indigenous microflora of humans are considered to be commensals.
True
True or False Middle ear and inner ear are usually sterile.
True
True or False Most relationships between humans and microbes are beneficial, rather than harmful.
True
True or False Outer ear and auditory canal contain the same microorganisms as on the skin.
True
True or False The colon is anaerobic.
True
True or False The male and female reproductive systems are usually sterile, with the exception of the vagina.
True
True or False The parasite may or may not cause disease in the host.
True
True or False Upper respiratory tract has an abundance of microorganisms. Many are harmless, some are opportunistic.
True
Which of the following would be present in highest numbers in the indigenous microbiota of the human mouth? a. Alpha-hemolytic streptococci b. Beta-hemolytic steptococci c. Candida albicans d. Staphylococcus aureus
a. alpha-hemolytic streptococci
Which of the following sites of the human body does not have indigenous microbiota? a. bloodstream b. colon c. distal urethra d. vagina
a. bloodstream
The greatest number and variety of indigenous microbiota of the human body live in or on the _____
a. colon
Which of the following are least likely to play a role in the nitrogen cycle? a. indigenous microbiota b. nitrifying and denitrifying bacteria c. nitrogen-fixing bacteria d. bacteria living in the root nodules of legumes
a. indigenous microbiota
Number and variety of microorganisms depend on _______
amount of moisture present, pH, temperature, salinity, and presence of chemical wastes and other microbes.
The delicate balance of the indigenous microflora can be upset by _______
antibiotics, other types of chemotherapy, and changes in pH
Which of the following would be present in highest numbers in the indigenous microbiota of the skin? a. C. albicans b. coagulase-negative staphylococci c. Enterococcus spp. d. E. coli
b. coagulase-negative staphylococci
The distal urethra and its external opening harbor many microbes including ______
bacteria, yeasts, and viruses.
How many species are indigenous microflora composed of?
between 500 and 1000 different species
Bacteria and yeasts used to stabilize the microbial balance are called _____
biotheapeutic agent or probiotics
Indigenous microflora are not found in the _______.
bloodstream
The indigenous microbiota of the external ear canal is most like the indigenous microbiota of the: a. colon b. mouth c. skin d. distal urethra
c. skin
The _____ (large intestine) contains the largest number and variety of microorganisms of any colonized area of the body.
colon
The greatest number and variety of indigenous microflora of the human body live in the _____
colon
Symbionts are classified as _____
commensal, opportunistic, parasitic
A symbiotic relationship that is beneficial to one symbiont and of no consequence to the other
commensalism
________ is a symbiotic relationship of benefit to one of the symbionts but neither beneficial nor harmful to the other.
commensalism
A symbiont could be a(n): a. commensal b. opportunist c. parasite d. all of the above
d. all of the above
Escherichia coli living in the human colon can be considered to be a(n): a. endosymbiont b. opportunist c. symbiont d. all of the above
d. all of the above
Microorganisms are used in which of the following industries? a. antibiotic b. chemical c. food, beer, and wine d. all of the above
d. all of the above
In the nitrogen cycle, soil organisms called_______ convert the nitrogen in nitrates to nitrogen gas in the atmosphere.
denitrifying bacteria.
Careless dental hygiene may cause:
dental caries, gingivitis, periodontitis
The GI tract is designed for _______
digestion of food, absorption of nutrients, and elimination of undigester materials.
Bacteria found within other microorganisms are known as ______
endosymbionts
A _____ is a living organism that harbors another living organism.
host
Microorganisms are present both on and in our bodies; collectively, they are referred to as our _______
indigenous microflora
The GU tract consists of the _____
kidneys, ureters, urinary bladder, urethra, and parts of the female/male reproductive systems.
Lower respiratory tract
larynx, trachea, bronchi, and lungs
Microbial antagonism means_____
microbes versus microbes
The study of the numerous interrelationships between microbes and the world around them
microbial ecology
A lichen is a classic example of ________
mutualism
A symbiotic relationship that is beneficial to both symbionts
mutualism
Upper respiratory tract
nasal passages and throat
Refers to a symbiotic relationship in which neither symbiont is affected by the relationship
neutralism
The term that best describes a symbiotic relationship in which two different microorganisms occupy the same ecologic niche but have absolutely no effect on the other is _________
neutralism
When two microorganisms occupying the same environment niche have absolutely no effect on each other, it is known as ______
neutralism
In the nitrogen cycle, soil organisms called ________ convert ammonia into nitrates, and nitrites into nitrates.
nitrifying bacteria
Microorganisms play an important role in the cycling of nutrients and elements like _____
nitrogen, carbon, oxygen, sulfur, and phosphorus.
In the nitrogen cycle, bacteria called ________ convert atmospheric nitrogen gas into ammonia in the soil
nitrogen-fixing bacteria
_______ live in the root nodules of legumes such as alfalfa and clover.
nitrogen-fixing bacteria
Bacteria in the colon are mostly ______
obligate aerotolerant and facultative anaerobes.
Many of the microflora of the colon are ______
opportunistic
A symbiotic relationship that is beneficial to one symbiont (the parasite) and detrimental to the other symbiont (the host)
parasitism
________ is a symbiotic relationship of benefit to one of the symbionts, and detrimental to the other.
parasitism
_______ are capable of converting the nitrogen within a dead plant or animal into ammonia in the soil.
saprophytes
Eye is lubricated and cleansed by tears, mucus, and _____
sebum
The organisms in the relationship are referred to as ______
symbionts
Bacterial vaginosis is an example of ________
synergism