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Advanced Higher Biology > Organisms And Evolution > Flashcards

Organisms And Evolution Flashcards

1
Q

Why do we sample

A

To get data and extrapolate an idea of what is going on in the population

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2
Q

What must we consider when taking samples

A 
Its the sample unbiased 
Is it representative 
The number of samples 
Accuracy and precision 
Designing your sampling 
Equipment 
Quantitative and qualitative 
Identification in your sample
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3
Q

How can a sample be unbiased

A

It can be structured and randomised

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4
Q

What makes a sample representative

A

You can justify assumptions and use statistics to extrapolate to the whole population

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5
Q

Why is the number of samples important

A

Generally the more samples collected the more reliable the survey
However the closer you look the better the sample but that may limit the number of samples you can take

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6
Q

Accuracy

A

A sample is accurate if it is close to the truth

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7
Q

Precision

A

A sample is precise if it obtains similar results

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8
Q

What does designing your sampling involve?

A

Pilot studies and early observations so the large sampling is done on the correct things

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9
Q

Define quantitative

A

Numerical data

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10
Q

Define qualitative

A

Data based on judgment

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11
Q

You’re data is only as good as the —– made in a sample

A

Identifications

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12
Q

What is important in choosing equipment?

A

Balancing cost, complexity, accuracy, training and time

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13
Q

For health and safety, what must be considered about terrain

A

How much the land goes up and down (what is underfoot)
What you will need to traverse
How difficult it will be to work in
(Eg a cultivated field will have easy terrain

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14
Q

For health and safety, what must be considered about weather conditions

A

The effects and dangers of the prevailing weather conditions
The possible extremes and their likelihood

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15
Q

For health and safety, what must be considered about isolation

A

(Not a likely issue in urban areas)
How do you know exactly where you are (sampling has to have positional data)
How quickly could someone come to your aid
Communication?
Nearest settlement?

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16
Q

For health and safety, what must be considered about contact with harmful organisms

A

Anything that can do harm eg bacteria, insects, larger animals

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17
Q

Point counts

A

Involves the observer recording all individuals from a fixed point. This can be compared to other count locations or with data from the same location gathered at other times

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18
Q

Quadrat

A

One of the most common methods for sampling organisms that are sliw moving or stationary
The frame is laid down and a direct count of what is in the frame or a percentage can be estimated
Only the squares containing the plants you are studying can be counted

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19
Q

Randomised sampling

A

Quadrats are often thrown to try to get a random sample. This is still not a truly random sample and other methods can be used to improve the randomisation

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20
Q

Line transect

A

A line (eg rope attached to a stake at either end) is laid out. At specific points along the line or across the whole line you record what is present or the presence or absence of a particular species

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21
Q

Belt transects

A

Uses two parallel lines and records the plants at given points
Using a quadrat at each section will give more accurate data

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22
Q

Quadrat and transects are used for

A

Sessile or slow moving organisms

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23
Q

Pit fall traps

A 
For mobile animals 
Can vary in size, access (fall triggered by size)
Baited or not 
Result of the fall (lethal or not)
Only effective for animals on ground
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24
Q

Sweep nets

A

Used for sampling in air or water

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25
Q

Water sweep nets

A

Often designed to allow water to flow out while collecting the organisms

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26
Q

Flight intercept traps

A

Fine black or white mesh that the insects fly into. Simplest design is just a screen

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27
Q

Malaise traps

A

Large tent like traps to catch flying insects

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28
Q

Pan traps

A

Can tempt flying insects. These are brightly coloured shallow dishes with a liquid that has low surface tension (eg soapy water) insects will be attracted to the colour, fly in and drown

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29
Q

Camera traps

A

For animals which are difficult to capture and where you want to avoid contact.
These cameras are activated by the animal at it approaches, normally using motion sensors or triggers like breaking a light gate

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30
Q

Scat sampling

A

Sampling the feaces can give you information such as the number, the range, the dna, the food and diet ant the health of the animal

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31
Q

Wjen sampeling wild organisms it is essential to….

A

Minimise impact on the community an habit
Especially when dealing with rare species and habitats
Some habits will also have specific legislation to protect them in place

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32
Q

Name 3 taxonomic groups

A

Nematodes
Arthropods
Chordates

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33
Q

How can animals be classed in the feild

A

Classification guides and keys
Observations and data that can be used with these later can be recorded
Expects often are able to rely on their own expertise

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34
Q

How can animals be classed in the lab

A

DNA analysis, protein markers and other cellular structures or molecules can be used
Particularly useful where visual identification is not clear or where differences between species are determined at cellular levels
Can be used in tracking species diversity and identifying individuals

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35
Q

Taxonomy

A

Taxonomy classified organisms by shared characteristics. This allows biologists to decide the name of a particular species
E.g panthera tigris
The more similar the full name the more similar the characteristics of the organisms

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36
Q

Phylogenetics

A

The use of sequence data, morphology and protein structure has allowed more detailed maps of the relationships between organisms to be produced. These are called phylogenetic trees or a phylogen
Helps map out relationships that can be obscured by divergent or convergent evolution

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37
Q

Divergent evolution

A

A shared common feature that has been adapted to serve different functions

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38
Q

Convergent evolution

A

Animals possessing similar features/ that are adapted to similar niches but come from different evolutionary paths

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39
Q

Model organisms

A

Species that have been studied extensively

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40
Q

How do indicator species help to monitor environmental impact

A

Either by presence or abundance
Understanding the tolerances of a particular species can mean you can use them as indicators for the environment or the community
A species that is absent/present shows they are susceptible/being favoured to some factors in the environment and

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41
Q

How can population size be determined

A

Sampling
A direct count of the population within a particular area can be used to give a whole population
Mark and recapture can be used

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42
Q

Mark and recapture

A

Involves capturing a sample of the population, marking and releasing the sample
After an interval of time a second sample is captured

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43
Q

What is the formula to estimate the total size of a population

A

N=MC/R

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44
Q

In N=MC/R, what is N

A

Population

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45
Q

In N=MC/R, what is M

A

Number captured and marked (1st sample)

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46
Q

In N=MC/R, what is C

A

Number captured and marked (2nd sample)

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47
Q

In N=MC/R, what is R

A

Number recaptured (mark caught in second sample)

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48
Q

What assumptions are made in using mark and recapture

A

All individuals have an equal chance of capture
No immigration or emigration in time interval between 1st and 2nd sample
Marked individuals can mix fully and randomly with the total population

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49
Q

Describe the marking method of banding

A

Bands with an individual identifier are attached to the individual
If it will not be possible or appropriate to physically recapture different colours can be used for removing identification

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50
Q

Describe the marking method of tagging

A

Tags used for remote tracking (radio transmitter)

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51
Q

Describe the marking method of surgical implementation

A

Tags can be implanted to prevent them interfering with the animal
For example so the don’t interfere with the streamlining of fush

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52
Q

Describe the marking method of painting

A

Animal is painted with non toxic biodegradable paints
Paint must not block skin surfaces for heat regulation, secretion or respiration
Impact of sent and colour must be considered

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53
Q

Describe the marking method of hair clipping

A

A clearly identifiable section of hair is removed

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54
Q

What is escherchia coli

A

A bacterium

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55
Q

What is caenirhabditis elegans (C. Elegans)

A

Nematode

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56
Q

What is arabidoopsis thaliana

A

Flowering plant

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57
Q

What is drosophila melanogaster

A

Arthropod

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58
Q

Name three chordates

A

Mouse
Rats
Zebrafish

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59
Q

Ethogram

A

A detailed list of all the behaviours in a particular species with clear descriptions of each behaviour

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60
Q

Describe a behaviour flow diagram

A

Arrows show moving from one to another

Thickness of arrow gives idea of frequency

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61
Q

What are the three main methods of sampling when using an ethogram

A

Occurrence sampling
Focal sampling
Scan sampling

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62
Q

Occurence sampling

A

Note the number of times a particular behaviour occurs by any of the animals present
Good for rare behaviours
Or when studying particular sub group
Does not give indication of the amount of time given to behaviour

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63
Q

Focal sampling

A

One particular individual is tracked through the time, noting every behaviour
Useful for allocating time budgets and pooling information from lots of individuals will give a lot of data
Very intense way of sampling

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64
Q

Scan sampling

A

At specific time intervals, noting what each animal is doing and where they are
Can be helped with te use if photographs

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65
Q

Anthropomorphism

A

A problem when studying animal behaviour

It is important to treat information in a scientific manner and not attribute human characteristics to non human species

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66
Q

Name three things that aid objectivity

A

Latency
Frequency
Duration

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67
Q

Latency

A

The time between a stimulus and response

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68
Q

Frequency

A

How often a particular behaviour occurs

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69
Q

Duration

A

The length of time a particular behaviour lasts

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70
Q

Tume budget

A

The time allocated to particular behaviours in a given time frame

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71
Q

Evolution

A

The change over time in the proportions of individuals in a population differing in one or more inherited traits

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72
Q

Name three ways Alleles can change in evolution

A

Natural selection
Sexual selection
Genetic drift

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73
Q

Natural selection

A

Non-random
Acts on genetic variation in populations when populations produce more offspring than the environment can support
Individuals with variations better suited to their environment tend to survive longer and produce more offspring passing on the advantage to the next generation

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74
Q

Sexual selection

A

Non random
The non-random process involving the selection of alleles that increase an individual’s chances of mating and producing offspring
May lead to sexual dimorphism
Can be due to male-male rivalry and female choice

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75
Q

Genetic drift

A

Random
Chance events cause unpredictable fluctuations in allele frequencies from one generation to the next.
More important in small populations as alleles are more likely to be lost from the gene pool

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76
Q

Describe the effects of bottleneck and founder effects on genetic drift

A

A gene pool is altered by genetic drift because certain alleles may be under-represented or over-represented and allele frequencies change

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77
Q

Where selection pressures are strong…

A

The rate of evolution can be rapid

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78
Q

Describe the hardy-Weinberg (hw) principle

A

In the absence of evolutionary influences, allele and genotype frequencies in a population with remain constant over the generations

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79
Q

Fitness

A

An indication of an individual’s ability to be successful at thriving and reproducing

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80
Q

Absolute fitness

A

The ratio between the number of individuals of a particular genome after selection to those before selection

81
Q

Relative fitness

A

The ratio of the number of surviving offspring per individual of a particular genotype to the number of survivors offspring per individual of the most successful genotype

82
Q

Co-evolution

A

The process by which two or more species evolve in response to selection pressures imposed by each other
A change in the traits of one species acts as a selection pressure on the other species
Frequently seen in pairs of species that have a symbiotic relationship

83
Q

Impacts of a symbiotic relationship

A

Can be positive (+) negative (-) or neutral (0) for the individuals involved
Mutualism, commensalism and parasitism are types of symbiotic relationship

84
Q

Red Queen hypothesis

A

In a co-evolutionary relationship, change in traits of once species can act as a selection pressure on other species. This means that the species in these relationships must adapt to avoid extinction

85
Q

Costs of sexual reproduction

A

Males unable to reproduce

Only half of each parents genome passed to offspring, disrupting successful genomes

86
Q

Benefits of sexual reproduction

A

Ought-weigh cost due to an increase in genetic variation
Provides the raw material for adaptation giving a better chance of survival under changing selection pressures and predators and parasites
Ubiquitous in higher organisms

87
Q

Benefits of Asexual reproduction

A

Maintaining the genome of the parent is successful in stable narrow niches or when re-colonising disturbed habitats
Offspring can be produced more often and in larger numbers

88
Q

Name two examples of asexual reproduction

A

Vegetative cloning in plants and parthenogenesis in lower plants and animals

89
Q

Parthenogenesis

A

More common in cooler climates disadvantageous to parasites or regions of low parasite density or diversity

90
Q

Horizontal gene transfer

A

Not able to adapt easily to changes in environment (mutations can occur that enable adaption to occur)
Organisms that reproduce Asexually often also have mechanisms of horizontal gene transfer between individuals to increase variation for example the plasmids of bacteria and yeasts
Allows faster evolution

91
Q

Gove some examples of asexual reproduction

A

Spider plants and strawberry plants produce runners

Some lizards are capable of parthenogenesis

92
Q

Examples of cloning in plants

A

Runners
Tubers
Bulbs
Plantlets

93
Q

Meiosis

A

Results in the production of two haploid gametes
Does not occur during asexual reproduction
Increases variation

94
Q

Gamete mother cells

A 
Only diploid cells capable of meiosis 
Located in sex organs
In animals: sperm in testes
                   Eggs in ovaries 
In plants: ovules in the ovary 
                Pollen in the anthers
95
Q

Haploid cells

A

One set of chromosomes (n)

96
Q

Diploid cells

A

Two sets of chromosomes (2n)

97
Q

Before meiosis begins…..

A

Each chromosome replicates forming two identical chromosomes help together by a centromere

98
Q

Meiosis 1

A

The diploid mother cell divides into two haploid cells

99
Q

Meiosis 2

A

The two haploid cells divide to form four haploid gametes

100
Q

Homoglous chromosomes

A

Pairs of chromosomes of the same size, same centromere position and the same genes at the same local
Although the genes are the same the chromosomes may he different
Each inherited from a different parent( 1paternal and 1 maternal

101
Q

Independent assortment

A

During meiosis 1 homoglous chromosomes pair up along the equator of the cells in q random and independent manner
Results in the production of gametes with varying combinations of maternal and paternal chromosomes

102
Q

The number of different combinations produced by an independent assortment can be calculated using the formula…

A

2^n where n is the haploid number

103
Q

What is the purpose of independent assortment

A

Results in new combinations of alleles and increased variation

104
Q

Crossing over

A

During meiosis one when homoglous amazons pair up the inner nonsister chromatids and cross over at points called chiasma
swapping genetic material results in the re-combination of alleles

105
Q

Linked genes

A

Genes on the same chromosome are said to be linked
The greater the distance between linked genes, the greater the chances of crossing over and the greater frequency of recombination

106
Q

Recombination frequency

A

Indicates a distance between linked jeans

107
Q

Gene mapping

A

Recombination frequency can be used to mark the position of linked genes on a chromosomes

108
Q

Sex determination

A

Sex chromosomes decide whether an individual is male (xy) or female(xx)
Males are hertogametic

109
Q

Sry gene

A

Responsible for the development of male characteristics

110
Q

Non-genetic (environmental) sex determination

A

Occurs when the sex of an organism can be altered during a sensitive period of development due to external factors such as temperature

111
Q

Temperature dependent sex determination (Tsd)

A

Where are the temperature experienced by the embryo during this temperature sensitive period of incubation determines sex
Most prevalent in reptiles

112
Q

Sex changes can occur as a result of

A

Change in size
Social interaction including competition
Parasite infection

113
Q

Sex ratios

A

The ratio of males to females in a population
Usually 1:1
The sex ratio of vertebrates can divide from 1:1 when influenced by resource availability and parental quality

114
Q

Sex allocation theory

A

The ability to shift offspring sex ratios represent an evolutionary adaptation for getting more offspring into the next generation, thus increasing fitness

115
Q

External fertilisation

A

In which both types of gametes are shed into the water and the sperm swim or are carried by currents to the eggs

116
Q

Internal fertilisation

A

In which eggs are retained within the reproductive tract of the female until after they have been fertilised by sperm inserted into the female by the male

117
Q

What organisms use external fertilisation

A

Animals in aquatic environments

Almost all aquatic invertebrates, most fish, many amphibians

118
Q

What organisms use internal fertilisation

A

Land animals

119
Q

External fertilisation advantages

A

Low energy cost of reproduction
Offspring need no parental care
Less energy used in courtship
Large numbers of offspring produced

120
Q

External fertilisation disadvantages

A

Restricted to wet environments

High chance offspring will not survive

121
Q

Internal fertilisation advantages

A

High chance offspring will survive

Able to reproduce on land

122
Q

Internal disadvantages

A

High energy cost of reproduction
Parents have to care for, protect and provide
Nourishment for their offspring
Less young produced

123
Q

R selected organisms

A

Occur in unstable environments, density dependent
Small, low energy reproduction, many offspring, earlier maturity, short life, each individual reproduces only once, die early, short generation

124
Q

K selected organisms

A

Occur in a stable environment, density dependent
Large, high energy reproduction, late maturity requiring long parental care, long life, reproduce multiple times, high survival, long generation

125
Q

Monogamy

A

One male mates with one female
Form life long pairs
Chosen strategy when young are venerable and require care from both parents

126
Q

Polygamy

A

An animal has more than one mate

127
Q

Polygyny

A

One male gets exclusive mating rights with multiple females

In some species only one of a few males in a group of females will mate

128
Q

Extra-pair copulation

A

A strategy used by females to avoid the sexual conflict caused by polygyny
Occurs as it is a disadvantage to the females for male choice to be limited

129
Q

Polygamy

A

When a female gets exclusive mating rights to multiple males

130
Q

Courtship

A

Specialised behaviours that attracts a member of the opposite sex and leads to mating

131
Q

Sexual selection

A

Mutual attraction is an important factor in mating

The presence of a particular trait among members of one sex can make them somehow more attractive to the opposite sex

132
Q

Conspicuous physical traits

A

Bright colouration, increased size, striking adornments and elaborate courtship make animals more visible to predators but grant greater success in obtaining mates

133
Q

Sexual dimorphism

A

A physical difference between males and females other than sex organs
A product of sexual selection

134
Q

Energy used in sperm production in comparison to egg production is relatively…

A

Low however they are made in larger quantities

135
Q

The r/k system

A

Organisms are categorised based on a level of parental investment and number of offspring produced

136
Q

Ecological niche

A

Summary of requirements and tolerances of a species

137
Q

Niche overlap leads to…

A

Competition

138
Q

Niche overlap occurs when…

A

Different species have similar resource requirements and tolerances

139
Q

Competition means that individuals have…

A

Less resources and hence lower survival chances

140
Q

Fundamental niche

A

The full niche an organism could occupy if there is no interspecific competition

141
Q

Partial nich

A

Occupied in response to interspecific competition

142
Q

Competitive exclusion

A

Occurs due to interspecific competition where the realised niches of two species are very similar
Called competitive exclusion because one species declines to local extinction

143
Q

Resource partitioning

A

Occurs due to interspecific competition Where the realised niches of the two species are sufficiently different
E.g individuals divide up a territory

144
Q

Parasite

A

A symbiont that gains benefit in terms of nutrients at the expense of its host

145
Q

The reproductive potential of the parasite is….

A

Greater than the host

146
Q

Why do parasites have asexual and sexual phases

A

Asexual phase allows rapid build up of parasites but no variation
Sexual phase allows rapid evolution

147
Q

Ectoparasite

A

Lives on surface of host

Ticks, lice

148
Q

Endoparasite

A

Lives within the host

Tapeworm , plasmodium

149
Q

What is meant by ‘many parasites are degenerate’

A

The host provides many of the parasites needs. Evolution has favoured the loss of non-useful organisms or structures. This means parasites have a narrow niche in which they can survive and breed

150
Q

Vector

A

An organism which plays an active role in the transmission of their parasite (may also be a host)

151
Q

Definitive host

A

Organisms on which or in which the parasite reaches sexual maturity

152
Q

Intermediate host

A

Organisms required to the parasite to complete its lifecycle/ asexual stage of parasites life cycle

153
Q

Transmission

A

Spread of parasite to host

154
Q

Virulence

A

Harm caused to a host species by a parasite

155
Q

More virulent parasites…

A

Have less chance for transmission

156
Q

Why is distribution of a parasite in a hosts population not uniform

A

Variation in host health
Variation in host immune system
Variation in host exposure to vectors
Variation in host behaviour

157
Q

Overcrowding of hosts increases…

A

Transmission rate

158
Q

In malaria and schistosomiasis infected hosts are often incapacitated. The parasites increase the transmission rate using….

A

Vectors

Water dispersal stages

159
Q

Give an example of host behaviour being used to maximise transmission

A

Schistosomiasis parasite released into water so can infect humansas they wade in the water

160
Q

Give an example of host behaviour being changed to maximise transmission

A

Rabies virus makes a dog more aggressive so it will bite and pass on diseases through saliva

161
Q

Describe the lifecycle of malaria

A

Caused by plasmodium
Mosquito acts as vector and bites human allowing plasmodium to enter bloodstream
Asexual reproduction occurs in the liver in red blood cells
When red blood cells burst, gametocytes are released into bloodstream
Mosquito bites an infected human and gametocytes enter mosquito
They mature into male and female gametes allowing sexual reproduction
The mosquito infects another human

162
Q

Describe the lifecycle of schistosomiasis

A

Caused by schistosomes
Reproduce sexually in human intestine
Fertilised eggs pass out with faeces into water where they develope into larvae
Larvae infect water snails where asexual reproduction occurs.
This produces a type of mobile larvae which escape the snail and penetrate the skin of a human, entering the bloodstream

163
Q

Methods of transmission used with ectoparasites

A

Direct contact

164
Q

Methods of transmission used with endoparasites of body cavities

A

Direct contact

Contribution of intermediate host

165
Q

Methods of transmission used with endoparasites of body tissue

A

Often transmitted by vectors

166
Q

Transmission

A

The spread of a parasite toa host

167
Q

Parasites can modify the hosts…

A

Foraging behaviour
Movement
Sexual behaviour
Habitat choice

168
Q

Some parasites can suppress the hosts immune system. This allows parasites to….

A

Grow and reproduce more efficiently

169
Q

Bacteria and viruses need….host species

170
Q

Viruses can only replicate…

A

Inside a host cell

171
Q

Viruses

A

Parasites that can only reproduce inside a host cell

172
Q

Animal viruses have

A

DNA

Protective coating

173
Q

Retroviruses have

A

RNA
Protective coating
phospholipid membrane from host material

174
Q

Viruses have outer surface….

A

Antigens which are used to attach to a host cell

175
Q

Antigens on viruses can sometimes be detected as…

A

Foreign by host immune system

176
Q

Describe DNA Viruses replication

A

Viruses antigens attach to host cell surface
Virus DNA genome is inserted into host cell
Virus DNA genome is replicated by hosts enzymes
Virus genes are transcribed to RNA and translated to make viral proteins
Virus particles are assembled and burst out of host cell

177
Q

Retrovirus replication

A

Changes RNA into DNA
Viral enzyme called reverse transcriptase is used to form DNA
new formed viral DNA is inserted into the genome of the host cell
Viral genes can be expressed to form new viral particles

178
Q

In an immune response to parasites by mammals the first line of defence involves

A

No specific defences: physical barriers

Chemical secretions

179
Q

Physical barriers

A

Epithelial tissue blocks entry

180
Q

Chemical secretions

A

Mucus saliva and tears all contain hydrolytic enzymes which destroy bacterial cell walls
Low ph caused by secretions in the stomach, vagina and sweat glands denatures cellular proteins of pathogens to destroy them

181
Q

Injured Cells release signal molecules this results in…

A

Enhance the bloodflow to the site bring antimicrobial proteins and phagocytes

182
Q

Describe the process of phagocytosis

A

Lysosomes contain powerful enzymes to kill parasites by engulfing them and storing them inside a vacuole

183
Q

Natural killer cells

A

Can identify and attach the cells infected with viruses releasing chemicals that lead to cell death by inducing apoptosis

184
Q

Lymphocytes

A

White blood cells found mainly in lymph glands
Each lymphocyte is part of a clone So each lymphocyte has just one type of receptor protein on the surface
Receptor proteins bind to a specific antigen

185
Q

Describe immune surveillance

A

Lymphocytes check the lymph fluid for antigens

Lymphocytes only activate if it’s receptor blind to its antigen

186
Q

What are the three types of lymphocytes

A

Killer T cells- induce apoptosis
Helper T cells
B cells- Produce antibodies

187
Q

Antibodies possess regions where the amino acid sequence vary greatly between different antibodies. Variable region gives the antibodies….

A

It’s specificity for binding antigens

188
Q

How do antibodies and inactivate parasites

A

When antigen binds to the binding site the antigen-antibody complex formed that can result inactivation of the parasite Rendering it susceptible to take a seat or can stimulate a response that result in cell lysis

189
Q

Describe memory lymphocytes and the secondary immune response

A

Initial antigen exposure produces lymphocyte cells self specific for that antigens that can produce a secondary response when the same antigen enters the body in the future when this occurs Antibody production is enhanced in terms of speed of production, concentration in the blood and duration

190
Q

Describe some strategies parasites have evolved to resist the immune system

A

Endoparasites can mimic host cell antigens and have a detection by immune system
Modify the hosts immune response reducing chance of destruction
Antigenic variation in subsequent generations involving. Evolving faster than the immune system can respond to new antigens

191
Q

Epidemiology

A

Study of outbreaks and spread of infectious disease

192
Q

Describe the difficulties in developing anti parasite medicines

A

Some Parasites are difficult the culture in the laboratory so there is no way to study the effects of treatment except using a host animal
Vaccines are difficult to develop as rapid antigen change after reflected in the design and the vaccine
I can also be difficult to find drug compounds that only target the parasite

193
Q

What are some non medicinal ways of controlling parasites

A

Attacking other parts of the parasites lifecycle

194
Q

Water born stages in a parasites lifecycle can be controlled by…

A

Civil engineering projects to improve sanitation

Parasites not transferred from human waste or bathing water

195
Q

Coordinated vector control

A

Reduces vector population and prevents vectors from infecting new hosts

196
Q

What allows parasites to spread rapidly

A 
Overcrowding (e.g refugee camps, many hosts close together with poor sanitation 
Tropical climates (warmer so parasites can survive away from hosts and vectors reproduce quickly )
197
Q

Parasite control allows

A

Reduced child mortality
Population wide improvement in child development and intelligence because kids are have more resources for growth and development

198
Q

LECDs

A

Less economically Developed Country

Advanced Higher Biology (3 decks)

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