Brainscape's Knowledge GenomeTM

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


See full index

Biology > Parasitism > Flashcards

Parasitism Flashcards

1
Q

What is an ecological niche?

A

A multi-dimensional summary of tolerances and requirements of a species

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

What is a fundamental niche?

A

The niche a species occupies in absence of any interspecific competition,

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

What is a realised niche?

A

Occupied in response to interspecific competition

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

What can happen as a result of interspecific competition?

A

Competitive exclusion can occur

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

When does competitive exclusion occur?

A

Where the niches of 2 species are so similar that one declines to local extinction

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

What can happen when realised niches are sufficiently different?

A

potential competitors can co-exist by resource partitioning

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

Parasitism is a ___________ relationship

A

symbiotic

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

How do parasite-host and predator-prey relationships differ?

A

Unlike in predator-prey relationships, the reproductive potential of the parasite is greater than that of the host

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

Why do most parasites have a narrow (specialised) niche?

A

because they are very host-specific

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

Why are many parasites degenerate?

A

Because the host provides so many of the parasite’s needs

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

What does degenerate mean?

A

lacking structures and organs found in other organisms

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

What is an ectoparasite?

A

Lives on the surface of its host

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

What is an endoparasite?

A

Lives within the tissues of its host

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

What is a vector?

A

A vector plays an active role in the transmission of the parasite and may also be a host

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

What causes the human disease Malaria?

A

Plasmodium

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

What causes the human disease schistosomiasis?

A

Schistosomes

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

What are viruses?

A

Viruses are parasites that can only replicate inside a host cell

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

Some viruses are surrounded by a

A

phospholipid membrane derived from host cell material

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

What do viruses contain?

A

genetic material in the form of DNA or RNA, packaged in a protective protein coat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does the outer surface of a virus contain?

A

antigens that a host cell may or may not be able to detect as foreign

21
Q

What is the importance of the enzyme reverse transcriptase?

A

RNA retroviruses use the enzyme reverse transcriptase to form DNA, which is then inserted into the genome of the host cell. Viral genes can then be expressed to form new viral particles

22
Q

What is the definitive host?

A

The organism in which the parasite reaches sexual maturity

23
Q

What is the intermediate host?

A

May also be required for the parasite to complete its life cycle

24
Q

What is transmission?

A

The spread of a parasite to a host

25
Q

What is virulence?

A

The harm caused to a host species by a parasite

26
Q

How are ectoparasites generally transmitted?

A

Through direct contact

27
Q

How are endoparasites generally transmitted?

A

By vectors or by consumption of intermediate hosts

28
Q

Factors that increase transmission rates?

A

*the overcrowding of hosts when they are at high density
* mechanisms, such as vectors and waterborne dispersal stages, that allow the parasite to spread even if infected hosts are incapacitated

29
Q

Examples of how host behaviour exploited and modified by parasites to maximise transmission?

A

Alteration of host foraging, movement, sexual behaviour, habitat choice or anti-predator behaviour.

30
Q

How do parasites modify the host’s behaviour in ways that benefit the parasite growth, reproduction or transmission?

A

Parasites often suppress the host immune system and modify host size and reproductive rate

31
Q

Non-specific immune defences

A

Physical barriers, chemical secretions, inflammatory response, phagocytes, and natural killer cells destroying cells infected with viruses

32
Q

What do epithelial tissue do?

A

blocks the entry of parasites;

33
Q

hydrolytic enzymes in mucus, saliva and
tears…

A

destroy bacterial cell walls

34
Q

low pH environments of the secretions of stomach, vagina and sweat glands…

A

denatures cellular proteins of pathogens.

35
Q

Specific cellular defences

A

A range of white blood cells constantly circulates, monitoring the tissues

36
Q

What happens if tissues become damaged or invaded?

A

Cells release cytokines that increase blood flow resulting in non-specific and specific white blood cells accumulating at the site of infection or tissue damage

37
Q

What does binding of an antigen to a lymphocyte’s receptor do?

A

selects that lymphocyte to then divide and produce a clonal population of this lymphocyte

38
Q

Different types of lymphocytes

A

Some selected lymphocytes will produce antibodies, others can induce apoptosis in parasite-infected cells

39
Q

Antibodies possess regions where the amino acid

A

sequence varies greatly between
different antibodies. This variable region gives the antibody its specificity for binding antigen

40
Q

Endoparasites mimic host antigens to

A

evade detection and modify host immune response: to reduce their chances of destruction

41
Q

Antigenic variation in some parasites allows them to

A

change between different antigens during the course of infection of a host It may also allow re-infection of the same host with the new variant

42
Q

Some viruses escape immune surveillance by

A

integrating their genome into host genomes existing in an inactive state known as latency
The virus becomes active again when favourable conditions arise

43
Q

What is epidemiology?

A

the study of the outbreak and spread of infectious disease

44
Q

What is the herd immunity threshold?

A

the density of resistant hosts in the population required to prevent an epidemic

45
Q

Vaccines contain

A

antigens that will elicit an immune response

46
Q

Drug designing difficulties?

A

The similarities between host and parasite metabolism makes it difficult to find drug compounds that only target the parasite

Antigenic variation has to be reflected in the design of vaccines

Some parasites are difficult to culture in the laboratory making it difficult to design vaccines

47
Q

What may be the only practical control strategies?

A

Civil engineering projects to improve sanitation combined with co-ordinated vector control

48
Q

Parasites spread rapidly because of

A

Overcrowding, tropical environments

49
Q

Improvements in parasite control reduce

A

child mortality and result in population-wide improvements in child development and intelligence, as individuals have more resources for growth and development

Biology (21 decks)

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