Disease Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

How do bacteria replicate?

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

3 ways to classify bacteria.

A

Staining

Shape

Clustering

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

2 staining outcomes.

A

Gram +

Gram -

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

4 bacteria shapes.

A

Cocci (spherical cells)

  • diplo = pairs
  • strepto = chains
  • staphylo = clusters

Bacilli (rod shaped)

Spirilla (spiral shaped)

Vibrio/filamentous (like a comma)

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

3 types of bacterial clusters.

A

Diplococci (pairs)

Streptococci (chains)

Staphylococci (cluster)

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

How do viruses replicate?

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

5 steps of viral replication.

A
  1. Adsorption
  2. Penetration
  3. Replication
  4. Assembly
  5. Release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the 1st stage of viral replication (adsorption).

A

Viral binds to the host cell.

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

Describe the 2nd stage of viral replication (penetration).

A

Virus injects its genome into host cell (DNA or RNA).

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

Describe the 3rd stage of viral replication (replication).

A

Viral genome replicates using the host’s cell machinery.

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

Describe the 4th stage of viral replication (assembly).

A

Viral components and enzymes are assembled into coats.

Genome is packaged inside.

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

Describe the 5th stage of viral replication (release).

A

Host cell lyses and many more viral particles can infect other cells within host.

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

Describe reverse transcriptase.

A

Some viral particles containing RNA use it to replicate

  1. RNA is converted to DNA.
  2. They use the host cell machinery to replicate their genome (make their protein coats and RNA genome).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What cells do viruses infect?

A

Any type of cell.

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

Define bacteriophages.

A

Viruses that infect bacteria.

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

How are viruses classified?

A

Their genome

Eg: double stranded DNA, single stranded DNA, single stranded RNA, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define diseases.

A

Any malfunctions of the body/part of the body of an organism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define pathogens.

A

Disease causing agents.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define infectious/communicable diseases.

A

Diseases that:

  • Can be transmitted from one organism to another.
  • Are caused by pathogens.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define non-infectious diseases.

A

Diseases that:

  • Cannot be transmitted from one organism to another.
  • Aren’t caused by pathogens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

2 non-cellular pathogens.

A

Viruses

Prions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe viruses.

A

Contains DNA or RNA

Molecule encased in a protein (or two protein layers) that may be covered in a lipid layer.

Shape varies greatly.

Much smaller than bacteria (0.5 to 0.01 times the size).

Can only reproduce inside a living host.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe prions.

A

Small infectious proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Example of a prion.

A

vCDJ (variant Creutzfeldt-Jakob disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

4 cellular pathogens.

A

Bacteria

Fungi

Protists

Minor groups of parasites

  • Endoparasites
  • Ectoparasites
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe bacteria.

A

Microscopic

Unicellular

Prokaryotic

No membrane bound organelles and nuclei.

Cell wall made of sugars and amino acids.

Single ‘spaghetti-like’ strand of DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Describe fungi.

A

Eukaryotic

Generally multicellular

Microscopic fungi are generally larger than bacteria.

Reproduce using spores.

Cell walls made of chitin (carbohydrate).

Contain hyphae (branching threads) that form a mass called a mycelium.

Hyphae are usually divided along their lengths by walls called septa that have pores in them to allow nutrients to pass from one cell to adjacent cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Describe protists.

A

Eukaryotic.

Can be unicellular or multicellular

Reproduce sexually and asexually.

Have no complex systems.

Have a variety of shapes depending on their locomotion.

Generally cannot move themselves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Describe endoparasites.

A

Live inside another organism – usually intestines

Some use other animals as intermediate hosts and humans are the definitive host.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Examples of endoparasites.

A

Flatworms

Roundworms

Flukes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe ectoparasites.

A

Live on the surface of another organism.

Many are vectors for other diseases such as the plague (bacteria).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Examples of ectoparasites.

A

Fleas

Ticks

Lice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Define virulence.

A

The intensity of the effect of the pathogen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Define susceptibility/resistance.

A

The level of response of an organism to a pathogen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Define symptoms.

A

Characteristic effects of a pathogen on the body.

Signs of the disease in the host.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Define incubation period.

A

The time between infection and the onset of symptoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

4 parts of a pathogenic infection.

A
  1. Infection
  2. Incubation
  3. Symptoms
  4. Recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Define endemic diseases.

A

Occur at a relatively constant rate within a population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Define sporadic diseases.

A

Uncommon

Occur irregularly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Define epidemics.

A

Occur when there is an increase in the number of cases of a disease within a population is above normal

Rapidly spread.

May be triggered by:

  • Increased virulence
  • Introduction into a novel setting
  • Changes in host’s susceptibility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Define pandemics.

A

An epidemic

Infects large numbers of humans over multiple populations/continents/worldwide.

Rapid spread over multiple populations/continents/worldwide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Factors involved in the spread of disease.

A

Climate

Population density (urbanisation)

Infrastructure

Urban areas susceptible to epidemics and pandemics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What are the hosts of Influenza (virus)?

A

Numerous animals

  • Humans
  • Mammals
  • Birds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What are the signs and symptoms of Influenza (virus)?

A

Fever

Sore throat

Cough may persist and gradually deteriorate for several weeks

Runny nose

Headache

Muscle pains

Lethargy

45
Q

What are the hosts of Ross River virus?

A

Humans

  • Mosquito (vector)
  • Animal (source such as kangaroo)
46
Q

What are the signs and symptoms of Ross River virus?

A

Stiff painful joints

Rash

Swollen lymph nodes

Reduced mobility

47
Q

What are the hosts of the Aussie bat lyssavirus?

A

Humans

  • Bats (particularly Flying foxes) appear to be a reservoir of the virus
48
Q

What are the signs and symptoms of the Aussie bat lyssavirus?

A

Paralysis

Convulsions

Delirium

Death

49
Q

What are the hosts of the viral diseases of honey bees?

A

Honeybees

  • Potentially mites (vector)
50
Q

What are the signs and symptoms of the viral diseases of honey bees?

A

Collapse of hive

Significant reduction in plant pollination

Leads to honey shortage

51
Q

What are the hosts of Tetanus (bacterial)?

A

Humans

Horses

Cattle

52
Q

What are the signs and symptoms of Tetanus (bacterial)?

A

Muscle spasms (lockjaw)

Swallowing and breathing difficulties (possible breathing failure)

Abnormal heart rhythms leading to high or low blood pressure.

Painful fits

Heart attacks

53
Q

What are the hosts of Tuberculosis (bacterial)?

A

Humans

Cattle

Pigs

Birds

Dogs

Cats

54
Q

What are the signs and symptoms of Tuberculosis (bacterial)?

A

Chronic cough

Coughing blood

Lethargy

Sweating

Weight loss

55
Q

What are the hosts of the Crown of Gall affecting plants (bacterial)?

A

Deciduous fruits

Vine (e.g. grapes)

Berry fruits

Vegetables

Ornamentals (e.g. roses)

56
Q

What are the signs and symptoms of the Crown of Gall affecting plants (bacterial)?

A

Small, pale lumps on upper root/stem

  • Develop into large asymmetrical growths
  • May stunt the growth of a young plant.

May kill plants that are stressed in dry conditions

57
Q

What are the hosts of Chytridiomycosis (amphibian chytrid fungus disease) (fungal)?

A

Amphibians

  • Frogs
58
Q

What are the signs and symptoms of Chytridiomycosis (amphibian chytrid fungus disease) (fungal)?

A

Loss in body weight

Lethargy

Skin colour changes

Shedding of skin

Convulsions

Death

59
Q

What are the hosts of Malaria (Protista)?

A

Humans

  • Mosquito (vector) (Anopheles genus)
60
Q

What are the signs and symptoms of Malaria (Protista)?

A

Fever

Hot and cold spells

Shaking

Headaches

Muscles aches

Weakness

61
Q

What are the hosts of Phytophthora dieback (Protista)?

A

Several native species of plants:

  • Eucalyptus
  • Grass tress
  • Banksia
62
Q

What are the signs and symptoms of Phytophthora dieback (Protista)?

A

Leaves may wilt then die (outer first progressing inwards towards trunk)

Roots may darken in colour

Most plants die, particularly if under water stress

63
Q

The spread of a specific disease involves what interrelated factors?

A

Growth of the pathogen population

Density of the host population

Mode of transmission

64
Q

What facilitates the transmission and spread of disease?

A

Regional/global movement of organisms

65
Q

Describe Dengue fever

A

Mosquitoadaptedd to living in urban environments as it can breed in artificial water pools (water tanks and buckets).

Can spread rapidly because of the high population density in urban environments and numerous water sources

66
Q

What are the vectors of Dengue fever?

A

Humans

  • Mosquitos (vector)
67
Q

What are the signs and symptoms of Dengue fever?

A

Fevers

Muscle aches

Headaches

Rashes

Death

68
Q

How do pathogens evolve?

A

Evolve in a changing environment

Bacteria divide/reproduce once every 20 mins under ideal conditions

Numerous opportunities for mutations

New strains produced

Opportunities for a more virulent strain is endless

69
Q

What do design interventions include?

A

Implementing programs

  • Vaccination programs
  • Quarantine measures
70
Q

Management strategies used to control the spread of infectious diseases.

A

Quarantine

Immunisation (herd immunity)

Disruption of pathogen life cycle

Medications – antibiotics and antivirals

Physical preventative measures

71
Q

Advantages of quarantine.

A

Prevent specific pathogens from crossing borders or entering a country

72
Q

Disadvantages of quarantine.

A

Inadequate checks by customs can result in a disease entering a country

Borders are porous to human and other organisms’ movements.

Illegal activities

Ignorance from travellers

73
Q

Advantages of immunisation (herd immunity).

A

If large proportion of population has immunity, the small number of population who are not immune are protected to some extent

They live in a population in which the spread of that disease will be interrupted or stopped by people who are immune

Greater proportion of people who are immune, greater protection of those within the population who are not immune

Mass vaccination creates a ‘herd immunity’ - whole population is protected

74
Q

Disadvantages of immunisation (herd immunity).

A

Large proportion of population decide not to have the treatment for themselves (or their children) - large population is at risk.

Epidemics are much more likely.

Resistant strains are more likely to develop in these circumstances that in time can affect the vaccinated.

75
Q

Advantages of the disruption of pathogen life cycle.

A

If disease is spread by vector, transmission can be interrupted if vector is eradicated

76
Q

Disadvantages of the disruption of pathogen life cycle.

A

Mosquito eradication programs (e.g. malaria) will not remove the mosquito entirely.

Insects become resistant to insecticides.

Removal of suitable breeding places not possible in tropics and sub-tropics where disease is endemic.

77
Q

Advantages of medications (antibiotics/antivirals).

A

Successful treatment for infectious disease (e.g. antibiotics) normally reduces transmission.

Early intervention (usually prior to becoming contagious) minimises spread.

78
Q

Disadvantages of medications (antibiotics/antivirals).

A

Pathogens frequently develop a resistance to drugs.

79
Q

Advantages of physical preventative measures.

A

Isolation necessary to reduce the spread.

Reduce exposure to public.

Special equipment used by health workers such as respirators, gloves and special clothing

Washing hands to prevent direct contact or faecal-oral routes.

Preventative measures include sterilisation of all soiled (contaminated) equipment, clothing, bedding and treatment of human wastes

Barriers such as condoms prevent the transmission of several venereal diseases (e.g. HIV)

Early diagnosis essential to containment

80
Q

Disadvantages of physical preventative measures.

A

Communicable diseases are still transferred to health workers and those closest to patients

May occur through error or ignorance of the disease

Health workers occasionally contact disease (e.g. Ebola in west Africa) despite protective clothing and masks

81
Q

Define nosocomial infections.

A

Infections spread by healthcare workers.

82
Q

Describe the immune system.

A

Made up of different cells that protect our bodies from foreign organisms

Homeostatic mechanism

Protects against foreign organisms, alien chemicals, cancerous/abnormal cells

83
Q

Define antigens.

A

Any substance capable of causing an immune response.

84
Q

Define antibodies.

A

Specialised proteins that are produced in response to a non-self antigen.

They attach to a specific antigen (lock and key model) and destroy or inactivate the foreign antigen

85
Q
A
86
Q

4 modes of action by antibodies to inactivate antigens.

A

Bind to Virus Surface

Coat Bacteria

Combine with Foreign Enzymes or Bacterial Toxins

Agglutination

87
Q

Describe the action of antigen binding to virus surface.

A

Prevent the viruses from entering cells

88
Q

Describe the action of antibodies coating the bacteria.

A

Bacteria are more easily consumed by phagocytes (white blood cells)

89
Q

Describe the action of antibodies combining with foreign enzymes or bacterial toxins.

A

Either one of these:

  • Inhibits reactions with other cells/compounds
  • Dissolves organisms
  • Reacts with soluble antigens and makes them insoluble
90
Q

Describe agglutination.

A

Causes particles (bacteria/viruses/foreign blood cells) to clump together

91
Q

Steps in immune response

A
  1. Primary response-first exposure to antigen
  2. Large amounts of antibodies are built up to fight antigen (takes several days)
  3. Primary response leaves the immune system with memory cells of the specific antigen
  4. Secondary response-subsequent exposures result in a much faster response because of the memory cells
92
Q

Define immunisation.

A

Programming of the immune system to allow the body to rapidly respond to infecting micro-organisms.

Results in a secondary response

Can occur naturally or artificially

93
Q
A
94
Q

Describe passive (no memory cells) immunity.

A

Natural

  • Antibodies enter bloodstream across the placenta/in breast milk

Artificial

  • Antibodies injected into bloodstream (snake antivenom)
95
Q

Describe active (memory cells) immunity.

A

Natural

  • Attack of a disease results in the ability to manufacture antibodies

Artificial

  • Antigens provided by a vaccination results in the ability to manufacture antibodies
96
Q

Define vaccination.

A

The artificial introduction of antigens of pathogenic organisms so that the person can produce a secondary response of antibodies without the person having to suffer the disease

97
Q

Define antibiotics.

A

Chemicals able to either:

  • Inhibit the growth of micro-organisms
  • Kill micro-organisms
98
Q

Define antiviral drugs.

A

Chemicals that disable viral proteins

99
Q

4 types of vaccines.

A

Living attenuated micro-organisms (reduced virulence)

Dead micro-organisms

Toxoids (inactivated toxins)

Sub-unit (fragment of the organism)

100
Q

What do living attenuated microorganisms protect against?

A

Measles

Mumps

Rubella

Rabies

Tuberculosis

101
Q

What do dead microorganisms protect against?

A

Cholera

Bubonic plague

Typhoid

Whooping cough

102
Q

What do toxoids protect against?

A

Tetanus

Diphtheria

103
Q

What do sub-units protect against?

A

Hepatitis B

Human papilloma virus (HPV)

104
Q

Define herd immunity.

A

When vaccinations reduce the chance of disease and increase the immunity of the population

When a particular proportion of a population is immune, susceptible individuals are also better protected.

105
Q

How are diseases classified?

A

Environmental

Genetic

Cardiovascular

Cancer

Injuries

Blood and immune system

Infectious and parasidic

106
Q

Define phages.

A

Viruses that infect bacteria.

107
Q

Define viroids.

A

Plant pathogens consisting of circular RNA.

108
Q

Define capsids.

A

Protein shells with the shape depending on the type of virus.