Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PL1003 > Topic 2 Microbiology - Microbiology > Flashcards

Topic 2 Microbiology - Microbiology Flashcards

1
Q

What are the 4 Koch’s Postulates?

A
  1. The organism responsible MUST be present in EVERY case
  2. It MUST be possible to isolate the organism from a diseased individual and grow it in pure culture
  3. It (the cultured microorganism) MUST be able to cause the disease when a healthy animal is infected with the pure culture
  4. The organism MUST be recoverable from an animal which has been experimentally infected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are examples of different types of microbes?

A

Bacteria, Fungi, Protozoa, Viruses, Algae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are some general properties of Bacteria?

A

Prokaryote

Lacks organelles

No nucleus

Unicellular

Small size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are some general properties of Algae?

A

Multi and unicellular

Eukaryotes

Photosynthetic

Capable of causing potent toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some general properties of Protozoa and Fungi?

A

Eukaryotes

Contain a nucleus - may even contain multiple nuclei

Contain organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are some general properties of viruses?

A

Incapable of independent life - require a host for replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are some examples of bacteria which can cause human diseases?

A

Escherichia coli – found in digestive tract

Neisseria gonorrhoeae – causes gonorrhoea

Clostridium tetani – causes tetanus

Mycobacterium tuberculosis – causes tuberculosis

Borrelia burgdorferi – causes Lyme Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are some examples of fungi relevant to humans?

A

Trichophyton rubrum – involved in athlete’s foot

Penicillium chrysogenum - source of penicillin

Aspergillus nidulans – involved in farmer’s lung

Saccharomyces cerevisiae – brewing and baking industries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some examples of protozoa associated with diseases?

A

Giardia lamblia – giardiasis (digestive tract infection)

Trypanosoma brucei – sleeping sickness

Entamoeba histolytica - amoebiasis (digestive tract infection)

Trichomonas vaginalis – trichomoniasis (STI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are some examples of viruses associated with diseases?

A

Human Immunodeficiency Virus

Ebolavirus

Hepatitis Viruses

West Nile Virus

Corona Virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are some examples of algae associated with diseases?

A

Gambierdiscus toxicus – ciguatera fish poisoning

Various – amnesic, paralytic, diarrheal, neurotoxic shellfish poisoning

Raphidiopsis raciborskii – Palm Island Mystery disease

Alexandrium catenella – Saxitoxin (nerve agent – classed as WMD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is a microbiome?

A

microbiota (microbial community) associated with an organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What species are most microbes in the human microbiome?

A

bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are biofilms?

A

bacteria that can attach to surfaces and grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are some factors influencing distribution of external microbial Flora?

A

Nutrients, moisture, temperature, pH, skin shedding, fluid osmolarity, potential inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do most bacteria tend to be found in the external microbial flora (skin)?

A

regions of skin with the most apocrine sweat glands

17
Q

What are the two groups of skin-associated microbes?

A

Resident microbes and transient microbes

18
Q

Describe transient microbes?

A

Transient microbes tend to come in contact with the skin and may attach.
however, conditions are often not favourable for them, and they cannot replicate and multiply, so die off.

19
Q

Describe resident microbes?

A

Resident population tend to have evolved to preserve their access to nutrients in this niche.
They often produce bacteriocins which can kill the transient species, or help resident specie to outcompete transients.

20
Q

What areas of the body tend to have higher numbers of transient microbes?

A

face, neck, hands

21
Q

What are transient microbes influenced by?

A

environmental, domestic and occupational factors

22
Q

How does an oral cavity provide an excellent environment for microbial growth?

A

Constant temperature, moist environment, ready supply of nutrients, range of surfaces for attachments

23
Q

In oral cavities, due to food and drink being ingested, there is a risk that the microbes will be washed away, therefore, microbes attach to surfaces and also form biofilms. What different attachment sites are available?

A

Tongue, epithelial cells, teeth, corners of the mouth/lips, gums

24
Q

What favourable conditions do nasal cavities provide for microbial growth?

A

moist conditions, relatively constant temperatures, nutritional sources from secretions

25
Q

When do microbes enter the nasal cavity/respiratory tract?

A

during inhalation

26
Q

Many species preferably live in the acidic conditions of the stomach. One such organism is Helicobacter pylori. Describe this organism in the stomach?

A

This is a major source of gastric ulcers.
Once into the stomach Helicobacter can colonise mucosal surfaces.
once attached it can cause inflammation and then ulceration

27
Q

The microbial community of the small intestine changes due to several variables. what are these variables?

A

age, diet, geographical distribution, antibiotic exposure, health, pH

28
Q

Give some examples of organism present in the small intestine?

A

enterococcus, bacteroides and lactobacillus

29
Q

What is the pH of the large intestine?

A

relatively neutral (4 to 7)

30
Q

Why is the rectal bacterial population very dense?

A

due to water being reabsorbed

31
Q

Bacterial population in the rectum produce several metabolites. what are these metabolites?

A

Hydrogen sulphide, methane, hydrogen and volatile fatty acids (VFAs)

32
Q

Most species of microbe in the human microbiome are bacteria. These colonise from birth onwards and the population changes over time. What are early colonisers said to be?

A

Commensal bacteria.

Commensals are those type of microbes that reside on either surface of the body or at mucosa without harming human health.

Commensalism is a long-term biological interaction in which members of one species gain benefits while those of the other species neither benefit nor are harmed.

33
Q

Describe factors of why commensal bacteria (early colonisers) have this type of symbiotic relationship

A

Access to nutrients
Defence
Multiple factors influence early colonisers
Diet
Environmental factors
Geographic location
Use of antibiotics

34
Q

What are bacteriocins?

A

Compounds that Kill transient bacteria to help resident bacteria to preserve their access to nutrients.

PL1003 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions