Term
|
Definition
Competition of several species for the same desired resource (can be avoided through environmental heterogeneity and resource partitioning)
The better exploiter of a resource will typically prevail
(eg Synedra excluding Asterionella) |
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Term
| Intraspecific competition |
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Definition
Competition of a desired resource within a single population of the same species
Such as cave beetles which were feeding on cricket eggs, where it was found that the depth, and frequency of their holes decreased with an increased population - causing an overall lower food consumption (density dependence)
Crowding effects results in predator abundance also being a contributing factor in consumption rates |
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Term
| Stratified random sampling / random sampling |
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Definition
Differ only by the method of sampling; random sampling is randomized through an entire test space while stratified random sampling is regarded as random sampling within set regions (will therefore also be able to detect changes within the test space)
Such as was used within diamond back moth research |
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Term
| Manipulative field experiments |
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Definition
In a manipulative field experiment, alteration on level(s) of the
predictor variable (or factor), and is then measured on how one or more variables of interest respond to these alterations (such as netting in the DBM experiment to remove natural enemies) |
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Term
| Bergmann's rule (temperature size rule) |
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Definition
Within a broadly distributed species; ones found in colder temperatures will be bigger, while ones found in warmer temperatures will be smaller
Due to radiation of less heat per body mass
Eg Moose found across Canada |
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Term
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Definition
Physiochemical features of an environment, such as temperature, pH and humidity
Alterations in immediate environments surrounding an organism
Is NOT consumed |
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Term
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Definition
Consumed by organisms in course of maintenance/growth/ reproduction etc
Eg carnivores consuming herbivores, herbivores consuming plants
Eg CO2 being used for plant growth along with nitrogen |
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Term
| Effect of temperature on growth |
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Definition
As a condition, temperature will typically increase growth (specifically within microorganisms) due to increased metabolism
This will however only extend to a certain temperature due to the denaturing of enzymes |
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Term
| Conditions facilitating interactions |
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Definition
Conditions affecting however species interact with each other
Camnula pellucida (grasshopper), basking in the sun to kill off Entomophaga grylli (fungus), which will become inhibited above 35C |
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Term
| Resources altering physiology |
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Definition
The way resources are consumed by a species
Eg root systems changing depending on the water required
Eg leaves falling off in the winter for maximum PAR
Eg leaves being angled differently to respond to available light or water |
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Term
| Interactions between resources and conditions |
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Definition
| Geographic patterns are a good example of an interacting effect from both, where conditions (such as climate) will dictate how a biome will be structured, which then will be dominated by certain plant species, facilitating specific species to live there |
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Term
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Definition
Area of land dominated by a certain subset of species which share similar characteristic traits
Eg physiological processes such as respiration |
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Term
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Definition
Sits around the equator with consistent rainfall and (high) PAR
Considered peak of biodiversity, due to reliable food resources for many specialists as well as a high floral diversity to go with it for pollinators
Has rapid soil decomposition, as well as most nutrients found within plants themselves |
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Term
|
Definition
Seasonal rainfall will restrict plant and animal diversity (reason for mass migrations (such as wilder beast))
Grazing animals are typically found with vast grasslands and scattered trees
Poor soil drainage means its very suceptible to drought and water logging - as well as fire due to the dry summer conditions |
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Term
|
Definition
Biome with seasonal temperature, and with very little rainfall at any point in a year (animal and plant diversity very low due to this)
Plants will either adopt a strategy to deal with it by having a very rapid growth set when water is present; or by having thick fleshy stems with hairy leaves which can go for prelonged periods of time in inactivity (eg cacti and succulents) |
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Term
|
Definition
Synchronous seasonal climate (hot, rainy summer; cold dry winter)
Frequented by grazing and fires
Typical hotspot for agriculture due to high organic matter in soil - has lead to being a highly affected biome |
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Term
| Temperate shrublands and woodlands |
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Definition
Has a distinctive asynchronous availability of light to rainfall
Will have regular fire (which will prevent succession from occurring due to constant secondary succession) - seeds are adapted as such |
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Term
| Temperate deciduous forest |
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Definition
Has synchronous light and rainfall, however will typically freeze over in the winter (high leaf loss)
Fertile soils will mean that leaves are are able to be replaced annually
Will have tall, vertical vegetation, along with some shrubbery |
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Term
| Temperate evergreen forest |
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Definition
| Synchronous rainfall to light, will however have a low diversity due to the nutrient poor soils which are affected by the pH of leaves |
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Term
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Definition
Will occur in high latitudes of the Northern Hemisphere - as such, will have high levels of permafrost (can be for several years)
Permafrost contains high levels of vital carbon which is important for growth through harsh conditions
Contains conifers, birch etc (hardy plants) |
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Term
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Definition
Characterized by permafrost and extremely high latitudes
Will generally only have shrubs, grasses, and sedges |
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Term
|
Definition
The observed change in species structure of an ecological community over time
Primary succession is succession in a location that was originally void of vegetation, and is based upon degradation of parent material
Secondary succession is succession which occurs after a disturbance in a community (the community can either bounce back or collapse) |
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Term
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Definition
The overall potential livable area of a species based on environmental conditions, as well as required resources
It does NOT take into account species competition |
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Term
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Definition
The more limited spectrum of conditions and resources where a species actually persists
ie taking into account competition
Eg White-Spotted Charr outcompeting Dolly Varden Charr due to temperature mediated mediated competition (aggressive behavior) |
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Term
| Co-existence competition example |
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Definition
There are 2 resources available (phosphate, silicate) to Cyclotella and Asterionella
At low densities of silicate, Cyclotella is able to out-compete due to it being a more efficient consumer of it
While at low densities of phosphate, Asterionell will be the more efficient competitor
However, when there is a similar amount of both, it becomes both of their realized niche |
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Term
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Definition
A group of species that have similar requirements and play a similar role within a community
eg rats and ants for competition within a guild |
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Term
| Competitive exclusion principle |
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Definition
| If two competing species co-exist in a stable environment, they do so as a result of niche differentiation (if no differentiation, then one will eliminate the other) |
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Term
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Definition
Species co-existing by using the same resource, but in a different way
Such as bacteria using different wavelengths of light in turbid and non-turbid waters
Or such as the use of complete metamorphosis for butterflies and moths to use the resources from plants differently, reducing intraspecific competition |
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Term
| Environmental heterogeneity |
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Definition
Due to environments rarely being stable, the instability of an environment will often lead way to a species which is a superior competitor, but also a superior colonizer which can take advantage of the instability
Eg sea palms growing within mussels of regularly disturbed waters |
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Term
| Organism weighted density |
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Definition
| Density based off a certain amount of species per resource (eg ladybeetles per plant, which found a smallest organism weight density, when distribution was uniform) |
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Term
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Definition
Assumes no competition, or anything else that affects birth or death rate
r will be constant and maximized
(r = rate of increase in net population) |
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Term
| Sigmoidal growth (S curve) |
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Definition
When the population is small, there is a very small amount of competition which allows the population to have a steep increase, and will reach the K value for that species afterwards (reducing r to 0)
(K= specific carrying capacity of a species) |
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Term
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Definition
Kill prey almost immediately; will kill multiple prey throughout life; will consume a majority of prey
Eg carnivores, insectivores, (even things such as venus fly traps will count) |
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Term
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Definition
Will consume multiple prey within their life; remove only part of each prey individual; effect on individual rarely lethal
Eg herbivores, blood suckers etc |
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Term
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Definition
| Consume part of their prey (rarely lethal); will have an intimate relationship with prey |
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Term
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Definition
| Typically insects, will have an intimate relationship with prey (like parasites), however after being laid into their prey, the prey will eventually die (like true predators) however it is not instant (grazers and parasites) |
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Term
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Definition
Occurs when a parasite's host is also a parasite
This is also loosely including parasitoids within this definition
As seen in the white cabbage moth examples |
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Term
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Definition
Will be reduced as a result of parasites and herbivores (as well as parastoids); this reduced fitness can lead to death (eg hunters killing unfit birds in culls), or less suitable circumstances
Eg Migrating pied flycatchers being infected by mites which results in later arrival of the mating season |
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Term
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Definition
Edible species resembles inedible in the same habitat - eg viceroy and monarchs
Is an individual defense mechanism |
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Term
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Definition
Unpalatable or venomous species share a similar colour pattern
Eg black and yellow stripes from yellow jackets to cinnabar moth caterpillars
(only has to experience one to known to avoid both) |
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Term
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Definition
Species with short handling time (short time between feeding) should be generalists (eg insectivorous birds)
Species with long handing time (long time between feeding) should be specialists (eg lions feeding on weak prey)
Areas with a low amount of productivity should have a very broad diet to compensate (eg bears eating nutrient poor salmon) |
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Term
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Definition
In absence of predators (P), the number of prey (N), will exponentially increase
In absence of prey, the number of prey will exponentially decrease
dN/dt=rN and dP/dt=-qP respectively |
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Term
| Lotka Volterra prey equation |
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Definition
Using the prey model with the factor of attack rate (a) of P to N
Gives dN/dt=rN-aPN for prey population
When no prey growth (P=r/a) |
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Term
| Lotka Volterra predator equation |
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Definition
Consumption of prey (aPN) and efficiency of offspring (f) combined with the general predator model gives:
dP/dt=faPN-qP
When no predator growth (n=q/fa) |
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Term
| Type I functional response |
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Definition
Linear increase met with a maximal point
Typical of filter feeders |
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Term
| Type II functional response |
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Definition
Predation rate rises at a decreasing rate to a maximum possible amount
Typical of predators |
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Term
| Type III functional response |
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Definition
Typical 'S' shape in rate of predation (low at first)
Rate of prey mortality increases with prey density
Can occur due to; refugees (protected at low densities, vulnerable a high); search images (better at searching in low densities) or prey switching (alternating on more abundant prey items) |
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Term
|
Definition
Predicts how long a predator should stay in a patch, before the cost outweighs the benefits
Is also based upon the time is takes to find the patch (thus long it takes to find the patch, the longer the individual will be there) |
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Term
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Definition
| Plants will be directly preventing herbivores through mechanisms such as toxins, repellents or digestion inhibitors (chemical) or physical prevention through waxy cuticles , trichrones (mites being trapped between trichrones) etc |
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Term
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Definition
| Mechanisms by which a plant will avoid herbivore indirectly; being advantageous to predators is ideal, which can often come hand in hand with signalling for other species |
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Term
| Inducible vs constitutive defences |
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Definition
Inducible will be triggered as a result of herbivory, however constitutive will be produced even in herbivory absense
The chinese cabbage and cabbage white moth is an example of inducible indirect defence (Jasmonic acid)
Inducible as a result will have lower fixed costs, however by the time they take effect, permanent damage may have already occured |
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Term
|
Definition
Shows relative abundance of various species
Will give general idea of trend and total species
Is difficult to use as a basis due to most species being difficult to study
Very few species are abundant** |
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Term
|
Definition
Will have many components/ intermediate steps as well as involving various processes such as physical, behavioral, biological, developmental etc
It is influenced by various environmental factors
Eg Tree pythons (living in trees), have behavioral and physical changes in the way they acquire their prey all in response to their new environmental requirements
Adaptions for pollination of Macrozamia species changes based upon specific pollinator and co-ordination of male and female cones |
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Term
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Definition
| A type of natural selection in which genetic diversity decreases and the population mean stabilizes on a particular trait value (important in complex adaptions because single traits are unlikely to be kept) |
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Term
|
Definition
In order for a species to complete it's life cycle, various processes must match to the environment in order for success
Eg bluebells timing their seed ripening and germination in accordance to the available water levels and temperature
Eg Adelle penguins and krill feeding
*must match sequence of thermal conditions in a locality* |
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Term
|
Definition
Organisms are typically found to be constantly redistributing themselves within a spatial scale
Such as; brown plant hoppers dying out each year in Japan, but reappearing through monsoonal activity; plant hoppers and their parasites appearing on grass on islands surrounding florida, to which are shortly after found to die out |
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Term
|
Definition
Constantly changes, potentially due to adaption to new conditions, or tracking of suitable conditions
Eg Pleistocene beetles |
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Term
|
Definition
The climatic influence on a species, ie species are affected by a different series of influences compared to that of another species
"Living conditions"
Does NOT include factoring for mutualists such as pollinators |
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Term
| Directional stabilization |
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Definition
A directional change in a certain aspect of a physical feature of a species (eg mandible length)
The amount of variability within a trait will however stay relatively constant
Can be coupled to environmental change |
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Term
|
Definition
| Is directionally selected for; as a result of imposing on a certain aspect of a species life cycle; effective function of complex adaptions |
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Term
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Definition
| Selection not forced to make change - occurs under specific conditions; small populations can result in fixation of a certain allele (depends on pop size) |
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Term
|
Definition
Must be widespread; non-native (by 15000y at least); must be introduced; and must have adverse effects
Can be as a result of adaptive change making them able to live successfully in other regions (eg muskrats and annual temperature) Must have high reproductive rate to be successful |
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Term
|
Definition
A group of populations interacting and coexisting in a location (larger than a population, smaller than an ecosystem)
(series of interacting species in theory, in practice its organisms which share clear boundaries) |
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Term
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Definition
| The measure of transfer of energy through a community (Tertiary, secondary, primary consumers, primary producers; Carnivore, carnivore, herbivore, autotroph) |
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Term
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Definition
Advanced version of trophic levels by also including many multilevel interactions with many species
- Excludes interactions which are not primarily food consumption
- does not include intra/ interspecific competition (fixed in interaction webs) |
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Term
| Community structure + assembly |
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Definition
Incorporates aspects of community attributes to species interactions and richness
How species 'fit' and their interactions will explain their ecological processes
The mechanisms behind this will explain the assembly |
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Term
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Definition
The no. and abundance of species
Components include relative abundance, species richness, composition and species evenness (shannon's index converted into pielou's evenness)
Rank abundance curves show aspects of this |
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Term
| Replacement series experiment |
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Definition
Method to determine the relative effect of one species on another in terms of biomass, reproduction etc
At differing percentages of species, individuals are tracked to see how they respond
Determines whether intra or interspecific effects are more important
Measured using a phytometer |
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Term
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Definition
| Most common species in a community, assumed to be due to competitive exclusion (best competitor, unless intransitive rather than transitive order of hierarchy, ie A > B > C > A not A >> B >> C) |
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Term
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Definition
| Species which have a role which is only filled by them - whilst having an extremely important function which many other species require, typically is not the most abundant species (impact disproportionate to abundance) |
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Term
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Definition
| Species which create a certain aspect in an ecosystem - without them there is a complete functional change |
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Term
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Definition
Quantifies links made within a community as well as assesses many links
Modules (more interactions with species within their own subsection than others
Peripherals (specialists; very few links within own module, as well as others)
Generalists (species that interact with many subsets of individuals) |
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Term
| Indirect Facilitation example |
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Definition
The effect of thinned vs thick carex on competing species
Carex and M guttatus both directly compete with M cardinalis (thinned will have a smaller effect which is usually taken up by the other)
There is however no effect of Carex on B figigun - however that will still compete with M guttatus
Therefore, the larger the effect of Carex on M guttatus, the better off B figigum will be |
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Term
| Community assembly processes |
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Definition
1. Dispersal and regional species pool; Dispersal ability (eg avoiding the seed shadow effect, or getting far away enough from competition)
2. Environmental filtering and niche compatibility; filtering through environmental filters (eg abiotic factor which dictates where a species can live), as well as determining where a species can prevail through competition (niche compatibility)
3. biotic interactions/ coexistance dynamics; competitive exclusion principle etc |
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Term
| Theories for community assembly processes |
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Definition
Theory 1, Limiting similarity: The more similar a subset of species are, the higher competition will be - thus less likely stable coexistence
Theory 2, Modern coexistence theory: Assumes one type of competitive difference - measured by fitness differences under circumstances (based on both the competitive difference AND the niche differences, therefore species can coexist if niche differences are greater than fitness differences) |
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Term
| Niche differences x Fitness ability differences |
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Definition
| Niche differences are the process of species having different niche's therefore promoting diversity (reducing negative effects of interspecific competition), whilst fitness ability dictates the better competitor for a particular resource decreasing species diversity (not density dependent, better competitor will live) |
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Term
| Stabilizing mechanisms: Variation independent mechanisms |
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Definition
| Resource partitioning (using resources in different ways); Predator partitioning (Species being attacked differently by different species); Frequency-dependent predation |
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Term
| Stabilizing mechanisms: Storage effect |
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Definition
Species are effected differently by spatial or temporal variation in the environment - stable coexistence with a superior competitor through avoidance in space or time (mediated by environmental heterogeneity)
Populations can "wait out" bad periods for growth of reproduction, by average there will still be positive growth, otherwise known as Buffering (spend most of life in least disturbed life stage Eg Californian peanuts) |
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Term
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Definition
Ecosystem processes stemming from biotic communities
4 hypotheses: Complementary (increase in species has a direct relationship to ecosystem function); Redundancy (increase in species will have direct relation relationship in ecosystem function until all required functions are filled); Driver and passenger hypothesis (relationship with species to function, however only moves in 'steps' for functions); and Driver and Passenger + Redundancy |
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Term
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Definition
Facilitation: early species benefit later species
Inhibition: early species inhibit later species
Tolerance: Interactions are not important and succession is attributed to innate species traits and life history
Can be any (or several) of these models for a particular environment (eg Alaska Bay which exhibits all 3) |
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Term
| > species in tropics theories |
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Definition
"cradle of diversity": High speciation rates relative to extinction rates, based on greater land area creating more species
"museum of diversity": Climatic stabilization relative to polar regions in which there is less disruption to diversification (once a species originates, they stay around)
Productivity and energy hypothesis: More resources in tropics, therefore higher productivity and k values for species, leads to faster evolution |
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Term
| Equilibrium Theory of Island Biogeography |
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Definition
The closer an island is, the higher the total species
The larger the island is, the lower the extinction rate |
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Term
|
Definition
All models are WRONG
However some can be used o predict what will happen within an environment
"Simplified representation of reality" |
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Term
|
Definition
Individual species in a given area potentially interbreeding (same gene pool)
In research, a population is what the researcher deems it to be
Metapopulations refer to a population of populations interacting with one another
Gene flow is also crutial |
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Term
|
Definition
Dispersal (inaccessible area)
Behavior (habitat selection)
Other species (predator / competition)
Physical / chemical influences (Ph, temp, moisture, light etc) |
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Term
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Definition
| Refers to changes in abundance and distribution "behavior in time and space" |
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Term
Define the term integument
~Cuticle & Exoskeleton~ |
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Definition
The cuticle, as well as he layer of cells below the cuticle known as the epidermis.
Culticle can be broken into endo and exocuticle (procuticle), with an epicuticle overlaying. |
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Term
What is the culticle in insects composed of?
~Cuticle & Exoskeleton~ |
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Definition
| Chitin microfibrils - Chitin being unbranched polysaccharide amino sugars. Typically sheet-like arrangements are seen within the microfibrils - linked together by a protein matrix |
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Term
What are the functions of the cuticle (External)
~Cuticle & Exoskeleton~ |
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Definition
Colouration
Protective covering
Antibiotic properties
Tools for cutting etc
Sensory |
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Term
What are the functions of the cuticle (Internal)
~Cuticle & Exoskeleton~ |
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Definition
Insulation
Muscle attachment sites (Apodeme?)
Flexibility
Organ support |
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Term
What is the dermal gland and pore canal used for?
~Cuticle & Exoskeleton~ |
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Definition
Secretions onto the surface - dermal gland
Secreting waxy coatings - Pore canal (much smaller) |
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Term
Why is the cuticle typically in a lamellate formation?
~Cuticle & Exoskeleton~ |
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Definition
| Microvilli producting chtin, move around within the epidermis, and as such each layer is oriented in a different direction (approximately spiral) - improves structural benefit |
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Term
What is the function of wax on the surface of the epicuticle?
~Cuticle & Exoskeleton~ |
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Definition
Water rention and resistance
Removal of hydrocarbons - taste cues - important for reproduction - produced by oenocytes and dermal glands |
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Term
What is tanning in insects?
~Cuticle & Exoskeleton~ |
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Definition
| Process by which the culticle becomes further sclerotized by use of proteins. These protein chains form bridges excluding water, and inducing drying (water insoluble). - only in exocuticle |
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Term
What is the use of melanin and how is it created?
~Cuticle & Exoskeleton~ |
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Definition
Made from excess dopemine used in the process of sclerotization.
Useful as an antibiotic layer, as well as UV photon shielding. |
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Term
Why may an insect not require sclerotization in the cuticle?
~Cuticle & Exoseleton~ |
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Definition
Typically to increase the amount of movement available eg some larvae and intersegment regions (eg between leg sections)
Honey pot ants, scale insects, plant feeding larvae, and diptera abdomens are examples of this. Honey pot ants intersegmental regions are able to strech the membranes in their abdomen in order for greater honey carriage. |
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Term
For instances where the cuticle needs to be tougher than other regions (eg chewing mouthparts, ovipositors), what differences can be seen?)
~Cuticle & Exoskelton~ |
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Definition
Incorperation of metals such as zinc, iron, manganese. Will always co-occur with halogens such as chlorine and/or bromine.
This can be seen in leaf cutter ants and termites especially.
In some instances, complete mineralization may also be seen such as muscid fly larvae, in order to avoid parasitism. |
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Term
What are the functions and properties of resilin in the cuticle?
~Cuticle & Exoskeleton~ |
|
Definition
Highly hydrated protein used in the joints and tendons of most insects.
It has been artificially created though genetic modification of Drosophile genes to be resilin coding in bacteria.
Particularly prominent at dragonfly wing muscle sites, and flea legs (plural arch, located internally in the metathorax). |
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Term
What are interference colours and pigmentation colours and how do they differ?
~Cuticle & Exoskeleton~ |
|
Definition
Light waves interfering with one another as they bounce off the cuticle shape (particularly in fine striated patterns or grating eg lepidoptera).
Pigmentation colours however are a chemical present in the cuticle which will absorb or reflect a particular wavelength, giving colour. Omatidia on the eyes may have pigmentation. |
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Term
What is light scattering and how does it work?
~Cuticle & Exoskeleton~ |
|
Definition
A creation of colour through the interaction of the roughness of a cuticle, to the wavelength of light put onto the cuticle.
Eg large irregularities provide white colour (large wavelgnths reflected), whereas small provide blue colour (reflecting only small wavelengths). |
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Term
Within the cuticle, what are restricting factors in relation to size?
~Cuticle & Exoskeleton~ |
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Definition
| Limitation of size through the exoskeleton being disproportionately larger, the larger the insect is. |
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Term
Describe the trachael system in relation to the cuticle
~Cuticle & Exoskeleton~ |
|
Definition
| The foregut, hindgut, and part of the reproductive system and respiratory system are all cuticle lined for structural support. Tissues with high metabolic activity will have a much higher tracheal activity. Tracheols will run between individual cell in order to provide oxygen. Spiracles are also chitin based - filters for dust or water from getting into the trachea. |
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Term
What are narrowarrays and how do they work?
~Cuticle & Exoskeleton~ |
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Definition
A narrowarray is a section of bumbs, so close together that light has no reflectance upon it (Btw 200nm and 300nm). This creates a continuous gradient of light channeled to a certain area, or away. Moths are flies are able to use the light onto their eyes more efficient, whereas some cicada wings can become essentially invisible at night.
Water also effects the ability of surfaces to be wet, forming balls rather than spreading out (lotus effect). This can then be used in cleaning practices, removing dirt particles, or as a water hydrophobic property, used in flight, or to stand on water. |
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Term
What are gland I cells?
~Glands &Secretions~ |
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Definition
Epidermal cells with the outter plasma membrane folded into microvilli. Secretion passes through canals between the microvilli and gland cell.
Typically released as pheramones.
Frequently clustered to form the gland. |
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Term
What are gland II cells?
~Glands & Secretions~ |
|
Definition
Cells derived from epidermal cells, however do not connect to the cuticle, nor have a duct. These cells include the oenocytes - which are released on the abdomen wall as hydrocarbons, to eventually become a waxy layer.
It is believed that lipophorins carries the hydrocarbons through the hemolymph to be released through the cuticle elsewhere. |
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Term
What are Gland III cells?
~Glands & Secretions~ |
|
Definition
They are the cells of a more complex "Unit" called "A class III dermal gland". Typically multicellular, with at least one cell set as a canal cell for transportation.
There is also an end apparatus responsible found in the cavity of the secreting cell for sorting secretions. Will also have microvilli where the secretion is released. |
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Term
In what respect are dermal glands important in a female's reproductive system?
~Glands & Secretions~ |
|
Definition
Often females will have a spermatheca used in storing sperm, in which this organ will be sclerotized. And posterior to this, there is a pair of accessory glands capable of secreting a glub-like substance which either binds the eggs to themselves, or the substrate (colleterial gland).
In some cases similar accessory glands are capable of producing silk, and as such are a modification of this simple premise. Whereas in bees and wasps, this accessory gland has been modified in all but the queen to secret toxic chemicals. |
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Term
What are metaplural glands?
~Glands & Secretion~ |
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Definition
| Glands found on an atrium of ants. At the base of a hair, each gland can be found. Gives some indication that dermal glands may have originated through sensory organs. |
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Term
What is a functional definition of silk?
~Silks~ |
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Definition
| Protein fibres spun by a number of arthropod lineages. Refers to the process of making an insoluble filament from an aqueous protein solution. |
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Term
What are labial gland silks?
~Labial silks~ |
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Definition
| They are glands which produce saliva for lubrication, and enzymatic functions upon food, however some have been modified to produce silk (Eg all lepidoptera, and glowworms; Arachnocampa) or venoms. |
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Term
What modification do lacewings have in terms of their colleterial glands?
~Other silks~ |
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Definition
| A modification which allows a silk substance to be excreted when laying eggs, forming a stalk like egg. |
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Term
What two factors drive gas exchange in insects?
~The Tracheal System~ |
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Definition
1. Passive diffusion of oxygen in the atmosphere directly into the muscles
2. Connective ventilation |
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Term
Describe diffusion and convection
~The Tracheal System~ |
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Definition
Diffusion: Kinetic movement of molecules from high to low concentrations - how gasses move from dead-ended tracheols across membranes
Convection: The bulk movement of molecules from high to low pressure - movement of large quantities of gasses over large distances |
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Term
What system of ordering does the insect respiratory (tracheal) system use?
~The Tracheal System~ |
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Definition
Spiracles - The opening allowing gas to pass through into the respiratory system (Can be opened or closed depending on what is required). Typically have hairs in the atrium to pretend bust and mites.
Trachea - The initial terminal after the spiracle opening. They are paired and run elongate along the insect. Responsible for the movement of gasses within the system. Using contraction and expansion, are able to drastically increase the efficiency in which gasses are channeled through opening and closing the spiracles.
Tracheols -Directly take or give gasses to muscles. Done through passive diffusion. |
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Term
Why is diffusion inefficient?
~The Tracheal System~ |
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Definition
Movement from a concentration gradient is slow due to the fact that there is no positive pressure on the molecules. As such, diffusion is slow, especially with the minuscule diameter of the trachea, and long distances. A fluid filled tracheal system would be even slower. (Rule of squares)
Therefore this is only efficient over minuscule distances. |
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Term
What is convective airflow?
~The Tracheal System~ |
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Definition
| A process known as auto-ventilation is typical in flying insects, where the activity of the flight muscles causes expansion and collapse or air sacs causing convective airflow. |
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Term
How can the pattern of closing and opening the spiracle in terms of oxygen intake and CO2 depositing be measured?
~Patterns of Respiratory Gas Exchange~ |
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Definition
Flow through respirometry.
Place animal in an enclosed space and measure the emergent O2 and CO2 from the other side.
Eg Continuous (High metabolic rate needed) vs Cyclic (at rest) vs Discontinuous DGC (independently evolving; low energy?) |
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Term
What is the Hygric hypothesis in terms of DGCs?
~Patterns of Respiratory Gas Exchange~ |
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Definition
| The hypothesis that DGCs evolved as a way of reducing water vapor loss that must accompany gasses. As such, the longer the spiracles are closed for, the lesser the water loss. This should show that insects living in arid areas are more likely to have this adaption, however this has not been found as of yet. |
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Term
What is the Cthonic hypothesis in terms of DGCs?
~Patterns of Respiratory Gas Exchange~ |
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Definition
| Its the hypothesis that states that DGCs evolved in response to environments with either low oxygen levels or high carbon dioxide levels. This then creates a greater concentration gradient to enhance gas exchange. This would imply that underground species would exhibit this, as many ants do, however this is not consistent. |
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Term
What is the Oxidative Damage hypothesis in terms of DGCs?
~Patterns of Respiratory Gas Exchange~ |
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Definition
| This is the hypothesis that states that DGCs reduce the overall exposure to oxygen, and therefore the reactiveness of oxygen. As such the breath holding and flutter phase could act to reduce tissue exposure to oxygen. |
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Term
What is the Emergent Property hypothesis in terms of DGCs?
~Patterns of Respiratory Gas Exchange~ |
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Definition
| The hypothesis that states that DGCs occur through reflexive response in gas levels. This therefore is a non adaptive trait. |
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