Quizz for DEB3

All options of a question can be true or false, independently of each other.

Go to chapters 01 02 03 04 05 06 07 08 09 10 11

Chapter 01: Basic concepts

01.01 When is an organism an isomorph?

true false
If it resembles a sphere.
If it resembles a cube.
If it resembles another organism.
If it does not change in shape during growth.

01.02 What is the difference between strong and weak homeostasis?

true false
Strong homeostasis refers to a strictly constant chemical composition; constancy is less strict under weak homeostasis.
Strong homeostasis applies to possibly varying conditions, weak homeostasis to constant conditions only.
Strong homeostasis implies constraints for reserve dynamics, weak homeostasis does not have these implications.

01.03 What is the implication if weak homeostasis is not assumed?

true false
The chemical composition of the organism can vary at varying food densities.
The chemical composition of the organism can vary at constant food densities.
Reserve dynamics is no longer determined by the partitionability requirement.

01.04 The structural homeostasis hypothesis

true false
gives a mechanism for weak homeostasis.
gives a mechanism for reserve dynamics as a first-order process on the basis of densities.
gives a mechanism for the relative size of organelles.
gives a mechanism for membrane dynamics.

01.05 A resting spore can be conceived of as

true false
an embryo, because it does not feed.
a juvenile, because it does not reproduce.
neither embryo or juvenile.

01.06 Do all rate parameters of the standard DEB model respond to temperature in the same way?

true false
Yes, because else conversion efficiencies become temperature dependent, which is not possible in the standard model.
Yes, but only if non-rate parameters depend on temperature as well.
No, all parameters can be effected by temperature in different ways, like by toxicants.
No, all rate parameters can be effected by temperature in different ways, like by toxicants.

01.07 Weak homeostasis has implications for reserve dynamics, strong homeostasis does not. Should they switch names?

true false
Yes, because weak homeostasis is more restrictive.
No, because you first need to identify pools before you can specify their dynamics.
No, because strong homeostasis always applies, weak homeostasis only at constant food.
No, because strong homeostasis applies to pools, weak homeostasis to the whole individual, which allows for weaker predictictions.

01.08 When are systems near the supply-end of the supply-demand spectrum?

true false
When reproduction is seasonal.
When growth depends on age.
When food consumption is independent of food availability.
When maintenance increases with food intake.

01.09 What is the definition of birth?

true false
Age is zero.
Initiation of development.
Initiation of feeding.

01.10 What is reserve?

true false
A pool of metabolites, set apart for later use when there is a need for it.
A pool of metabolites that is synthesized from food/substrate and is always used for metabolism.
A pool of metabolites that contributes to metabolic memory.

Chapter 02: Standard DEB model

02.01 How should we measure an organism's surface area to quantify changes in feeding rates.

true false
By coating the organism with a constant thickness, and measure the amount of coat.
By using the approximation that it is isomorphic, measure its length, and take surface area proportional to squared length.
By using the approximation that it is isomorphic, measure its volume, while surface area is proportional to volume to the power 2/3.
We again have the difference between physical and structural volume.
Effects on digestion are compensated by decreasing gut surface area per gut volume.

02.02 Does a big egg take a longer incubation time than a small egg?

true false
No, it needs a shorter incubation time if the amount of initial reserves is the only difference.
Yes, because large eggs result in large neonates, which take longer to develop.
Egg size is independent of incubation time.

02.03 What is the difference between egg and foetal development?

true false
A foetus gets food during development, while an egg has to rely on internal reserves.
Especially precocial species experience a decrease in developmental rate prior to hatching.

02.04 How can we tell structure apart from reserve in a DEB model?

true false
We can never separate structure from reserve in amounts or composition.
We can never assign a particular molecule to either reserve or structure.
We can obtain the chemical composition of structure and reserve from observations on the chemical composition of biomass at different growth rates.
Reserve consists of special chemical compounds that are not present in the structure, such as lipids and starch.

02.05 Given a specified investment into reproduction and the existence of a reserve and structure compartment, what are the degrees of freedom for the production of neonates?

true false
We can increase the amount of neonates' structure at the expense of the reproduction rate.
We can increase the amount of neonates' reserve at the expense of the reproduction rate.
We can increase the incubation time.

02.06 Why does reproduction not affect assimilation, growth or maintenance in the standard DEB model?

true false
Because energy investment in reproduction is small.
Because energy required for reproduction is extracted from food by an increased digestion efficiency.
Because reproduction is at the expense of development.

02.07 Do embryos and juveniles differ substantially in the following respect?

true false
Embryos gain energy from reserves, juveniles from food.
The specific maintenance costs for juveniles are much higher because of their increased activity.
The specific growth costs are much higher for embryos as compared with juveniles.
Juveniles start allocate to reproduction, embryo's don't.

02.08 What is the definition of the dissipating flux?

true false
The collection of fluxes that dissipate.
Maintenance, maturation plus reproduction overheads.
The collection of fluxes in which reserve is fully mineralized.
Maintenance plus growth overheads.

02.09 What is the immediate effect of an increase of energy conductance?

true false
The reserve capacity goes down.
The growth rate increases.
The maturation or reproduction rate increases.
The assimilation rate increases.

02.10 What is the long-term effect of an increase of energy conductance?

true false
The ultimate amount of structure goes up.
The ultimate body weight goes down.
The ultimate reproduction rate goes up.

Chapter 03: Metabolism

03.01 Why is it important to express product formation of enzymes in terms of arrival rates, rather than concentrations of substrates?

true false
Because (production) rates are then functions of (arrival) rates, which give less problems in applications than rates as functions of concentrations.
Because concentrations imply a homogeneous environment.
Because then it is easier to make mass balances.

03.02 When will product formation by enzymes be infinitely large at constant arrival fluxes of substrates?

true false
If substrate concentrations are infinitely large.
If the amount of enzyme is infinitely large.
If substrate handling time of an enzyme is infinitely short.

03.03 What are major differences between auto- and heterotrophs?

true false
Their assimilation routes.
Their use of internal reserves.
The chemical composition of internal reserves.
Their maintenance requirements.
The way in which they grow.

03.04 What is a C-mol?

true false
A mole of a compound that contains carbon.
An amount of organic compound, such that its weight equals its molecular weight times Avogadro's number.
An amount of organic compound, such that its weight equals that of a mole of carbon.
An amount of a mixture of compounds, such that the number of C-atoms equals Avogadro's number.
An amount of compound, such that its weight equals Avogadro's number times its molecular weight divided the number of C-atoms per molecule.

03.05 What is the difference between sequential and parallel processing?

true false
The SU binds each arriving molecule of each type one after the other in sequential processing, but can do so simultaneously in parallel processing.
The SU binds first one type, and then the other sequentially, and can do so simultaneously in parallel processing.
There are no fundamental differences between sequential and parallel processing.

03.06 When is it essential to measure energies, or energy fluxes?

true false
If we want to predict energy fluxes.
If we want to predict mass fluxes.
If we want to predict effects of temperature.

03.07 Why is it important to make mass balances?

true false
To test experimental data on their consistency.
To increase the accuracy of the measurements.
To test models on their consistency.
To make sure that models are complete.
Mass balances are rarely important.

03.08 The single most useful measures for biomass are

true false
C-moles, because mass balances require them.
Weights, because they are easy to measure.
Lengths, because we need volumes and surface areas to quantify maintenance and feeding.
Enthalpies, because these quantify nutritional values.
Carbon contents, because these quantify nutritional values.

03.09 When does the water content of structure exceeds that of reserve?

true false
If the relative decrease of dry weight during starvation is less then that of wet weight.
If the dry weight over wet weight ratio is less than average.
If the weight-specific water intake increases during growth at constant food.

03.10 Is respiration a good quantifier for metabolic rate?

true false
Sure, the literature is using this for more than a century.
No, anearobic organisms are metabolically active, but do not use dioxygen.
No, reproduction represents metabolic activity, but hardly contributes to the use of dioxygen.
The best quantifier is the dissipation of entropy.

Chapter 04: Univariate DEB models

04.01 Why is heat production a weighted sum of di-oxygen consumption, carbon dioxide production and nitrogen-waste production?

true false
Because these mineral fluxes contribute most to heat production in all cellular transformations.
Because di-oxygen is used to burn eventually all cell's organic compounds to carbon dioxide and nitrogen waste.
All transformations are weighted sums of assimilation, dissipation and growth.
Heat production is not such a weighted sum, because all transformations are weighted sums of assimilation, dissipation, growth and reproduction.

04.02 Why is the reserve flux negative during the embryonic period, and positive during the juvenile and adult ones at constant food density?

true false
Because growth is from reserves in embryo's and from food in juvenile and adults.
Because reserve synthesis exceeds reserve consumption in juveniles and adults.
Because juveniles and adults synthesize reserves from food, and embryos do not.

04.03 Does DNA belong to the structure, and not to the reserve?

true false
Yes, because DNA is not used for nutrient of energy storage.
Yes, because the weight-specific DNA content is independent of the growth rate.
Yes, because DNA repair mechanisms can be interpreted as maintenance, which is not required for reserves.

04.04 Fully grown water fleas continue moulting during starvation. Does this observation allow to link moult production to a basic energy flux?

true false
Moult production is only associated with assimilation.
Moult production is only associated with growth.
Moult production is only associated with maintenance.

04.05 Is it possible to partition di-oxygen consumption into contributions from assimilation, dissipation and growth?

true false
Yes, but only in a way that involves extra assumptions about energy allocation.
Yes, but only if the composition of food, faeces, reserve and structure are known.
No, an increase of di-oxygen consumption with assimilation can balance a decrease with maintenance, without being noticed from whole-organism responses.

04.06 Can reproduction rate, expressed as number of offspring per time, be written as a weighted sum of assimilation, dissipation and growth?

true false
Yes, because it is a flux and can therefore be written as such.
No, because reserves in produced embryos plus own reserves can be written as such, and not one of them separately.

04.07 Are changing food conditions more informative for energetics than constant conditions?

true false
than a set of different constant food conditions?
No, if the number of data points is small.
Yes, because the changes in body composition give information about the composition of reserve and structure.
Yes, because it reveals reserve dynamics and allocation rules.

04.08 Why does a constant respiration, urination and watering quotient imply that reserve and structure have the same composition?

true false
Because three constraints eliminate three degrees of freedom in the relative abundances of carbon, hydrogen, oxygen and nitrogen.
Because the constant respiration quotient implies that the carbon/oxygen ratios of reserve and structure are the same; the constant other two quotients have similar implications for nitrogen and hydrogen, respectively.
The constant three quotients do not imply that the compositions of reserve and structure are the same.

04.09 Why can the mineral fluxes be found from the organic fluxes?

true false
Because the number of mineral fluxes equals the number of elemental balance equations.
Because they determine dissipating heat, and heat determines the mineral fluxes on the basis of indirect calorimetry.
They do so only if the elemental composition of the organic compounds are known, and that of the reserve has to differ from that of the structure.

04.10 Can a product of a V1-morph always disappear, rather than appear, in association with ...

true false
assimilation?
maintenance or dissipation?
growth?

04.11 Ribosomal RNA cannot belong to the reserve,

true false
because it is subjected to turnover, so to maintenance, which makes it part of the structure.
because it catalizes protein synthesis, and is no source for nutrients or energy.
because the weight-specific rRNA content is constant as a function of growth rate.

04.12 Crusts differ from films and sheets because

true false
they are thinner.
they are thicker.
they have a limited extension.
they have different maintenance requirements.

Chapter 05: Multivariate DEB models

05.01 Can a mother-foetus system be considered as a two-reserve, two-structure system?

true false
Yes, if translocation is large relative to foetal utilization.
No, because foetal assimilation is non-existent.

05.02 Glucose and fructose are parallelly processed by bacteria

true false
because they are taken up by different carriers.
No, their uptake still interferes.

05.03 What are necessary (but not sufficient) conditions for a multi-reserve model to simplify to a single-reserve one?

true false
The assimilation rates of the different substrates must be proportional.
The composition of the different reserves must be identical.
The turnover rates must be equal.
The turnover rates must be large, except for one reserve.
All rejected reserves must be excreted.

05.04 Why is it hard to interpret photosynthesis-irradiance curves?

true false
Because the time-period for measurement affects the results.
Because many processes contribute to net di-oxygen production.
Because other factors, such as nitrogen availability, affect PI-curves.

05.05 Does the non-limiting reserve increase with the growth rate?

true false
Yes, if unused reserves are excreted.
No, if unused reserves are fed back to the reserves.
It can have an optimum relationship with the growth rate.

05.06 Product formation can be written as a weighted sum of assimilation, dissipation and growth in an single-reserve, single-structure model. How many fluxes must be considered in a two-reserve model?

true false
2 assimilation fluxes, 1 dissipation, 1 growth flux.
2 assimilation fluxes, 2 excretion, 1 dissipation, 1 growth flux.
2 assimilation fluxes, 2 excretion, 2 dissipation, 1 growth flux.

05.07 What is the CO2-compensation point in photosynthesis?

true false
A carbon dioxide concentration above which it is non-limiting.
The di-oxygen concentration above which it becomes toxic.
The ratio of carbon dioxide and di-oxygen concentration at which photorespiration equals photosynthesis.

05.08 Do plants grow during a dark night?

true false
No, plants need light to grow.
Only C4-plants do, but C3-plants do not.
Only plants that are heterotrophic.

05.09 Why is excretion required for multiple reserve DEB systems?

true false
Excretion is never required.
Excretion only occurs for reserves in excess.
To avoid unbounded accumulation of reserves if they would be in excess.

05.10 How can we include an increase in heart volume in response to prolonged sporting?

true false
We need multiple reserves for that.
We need multiple structures for that, with a static generalisation of the kappa-rule.
We need multiple structures for that, with a dynamic generalisation of the kappa-rule and adjustable maintenance.

Chapter 06: Effects of compounds

06.01 Is there any difference between first-order and one-compartment kinetics?

true false
These two types of kinetics are always identical. The only difference is in the interpretation of the changing variable; this is internal concentration in one-compartment kinetics, while it can be anything in first-order kinetics.
First order kinetics is based on diffusion, one-compartment kinetics makes another assumption on transport of compound.
One-compartment kinetics only implicates that we deal with a single compartment, which can have many different types of kinetics. First order kinetics is just one possibility.

06.02 Toxicokinetics can be specified in terms of a set differential equations for the internal and external concentrations or in terms of concentrations as functions of time. Are these specifications equivalent?

true false
Yes, if the initial conditions are specified as well.
Yes, but when it comes to fit the model to data, the explicit functions are much easier to work with.
Yes, but the set of differential equations is much easier to work with when we want to study or modify the mechanisms that are incorporated in the model.

06.03 Does the growth of an organism during exposure affect toxicokinetics?

true false
No, as long as this growth does not affect the external concentration.
Yes, because uptake is enhenced by the uptake of compounds that are necessary for growth.
Yes, because the surface that is involved in exchange is affected and the internal compound is diluted by growth, while the elimination flux depends on the internal concentration.

06.04 What is the definition of the LC50 for some exposure time?

true false
The estimated concentration at which the mortality probability is 50 percent of that in the control?
The estimated concentration at which the survival probability is 50 percent of that in the control?
The estimated concentration at which 50 percent of the initial amount of individuals died?
The highest tested concentration with no more than 50 percent mortality.

06.05 Suppose that we have two toxic compounds that differ in the elimination rate, but the accumulation rate and the toxicity per molecule are the same. Do these compounds have the same NEC?

true false
The NECs are the same because the compounds have the same toxicity. The only difference is that we have to wait longer for effects for the compound with the smallest elimination rate.
The NECs differ because we have to wait longer for effects for the compound with the smallest elimination rate. Therefore, the effects at the end of the bioassay are less for the compound with the smallest elimination rate.
The NECs differ because we have to wait longer for effects for the compound with the largest elimination rate. Therefore, the effects at the end of the bioassay are less for the compound with the largest elimination rate.

06.06 Suppose that we have two toxic compounds that differ in the elimination and the accumulation rate, but the BCF and the toxicity per molecule are the same. Do these compounds have the same NEC and LC50 at a standardized exposure time?

true false
The NECs are the same, but the LC50 for the compound with the larger rates is smaller.
The NECs are the same, but the LC50 for the compound with the larger rates is larger.
The compounds are equally toxic, so the NEC and the LC50 are the same.
The LC50s are the same, but the NEC for the compound with the larger rates is smaller.

06.07 Do LC50s always decrease for increasing exposure time to a toxic compound in a constant concentration?

true false
The LC50 can be constant, and sometimes even increase.
LC50's always decrease in time, but the rate of decrease decreases in time.
LC50's always decrease in time, but the rate of decrease can be constant or even increase in time.

06.08 Suppose that we two bioassays on survival/immobilisation and we test a compound using guppies with a relatively small body size in bioassay 1 and a somewhat larger body size in bioassay 2. The bioassays are otherwise identical. Do we expect the same NEC and LC50 at a standardized exposure time, apart from ``noise''?

true false
The NECs and the LC50s are the same, because they only depend on the type of compound and the species of organism.
The NECs are the same but the LC50 for bioassay 2 will be larger.
The LC50s are the same, but the NEC for bioassay 1 is smaller.

06.09 From what data are blank mortality rates estimated in the linear hazard model?

true false
From all survival data, the blank is not even necessary.
From all survival data, but it should include the blank.
From survival data in the blank only; we cannot be sure about the cause of death during exposure to a toxic compound.

06.10 Does the observation of no mortality in the blank imply that the blank mortality rate is zero in bioassays for survival?

true false
Yes, this is the the meaning that the blank mortality rate.
No, it also depends on survival data during exposure to the toxic compound.

06.11 What is the ratio between the NEC and the LC50 at very long exposure time, given the linear hazard model.

true false
This can be any number less than one, depending on parameter values.
This can be any number, depending on parameter values.
Yes, the (maximum) slope of the concentration-survival curve increases with the elimination rate.

06.12 When is death due to aging?

true false
If it is not due to starvation, disease or accident.
If secondary signs of aging are well developed and obvious alternative explanations are not applicable.
If age exceeds a minimum value and obvious alternative explanations are not applicable.

06.13 Can all parameters of the linear hazard model be estimated from survival data at a single concentration of toxic compound?

true false
No, we need several concentrations to determine the concentration-response relationship.
No, we need at least two concentrations with partial effect.
Yes, a single concentration is sufficient if we have enough observations in time.

06.14 Given a certain toxic compound, what will be the expected ratio of the LC50.1d for 1 mg guppies and the LC50.2d for 2 mg guppies?

true false
One, because the difference in body weight chancels against that in exposure time.
Less than one, because the extension of exposure period undercompensates the ratio in weights.
More than one, because the extension of exposure period overcompensates the ratio in weights.

06.15 Do you expect effects of an increase in temperature for the NEC and for the LC50 at a standardized exposure time?

true false
Temperature might affect toxicity, but the effect cannot be predicted.
The NEC will not be affected, but the LC50 increases with temperature.
Both the NEC and the LC50 will decrease with temperature.

06.16 Does the NEC conceptually correspond with the highest concentration at which no effects will show up at a standardized exposure time?

true false
No, that highest concentration corresponds with the EC0 for the given exposure time, while the NEC refers to very long exposure times.
Yes, the NEC stands for the EC0.

06.17 The number of surviving individuals at a given exposure time to a toxic compound in a certain concentration is assumed to be binomially distributed. What does this assumption imply?

true false
The individuals die and/or survive indepently. So the death of one individual does not affect the survival of another.
The variance of the number of surviving individuals only depends on the number of individuals and the survival probability, and not on the differences between individuals. So the variance will not increase when the differences between the individuals increase.
All individuals die with exactly the same probability.
If the survival depends on the internal concentration, all individuals are assume to have exactly the same internal concentration.

06.18 Does a certain reduction of the cumulative number of offspring per female at a standardized exposure period have a predictable reduction on the population growth rate?

true false
Yes, the population growth rate will be reduced by the same factor.
Yes, but only if the food supply is identical
No, population growth rate also depends on the moment at which reproduction starts.
No, we need to know the mode of action in the energy budget.
Yes, it does not matter when reproduction is repressed, the cumulative effect is all that counts.

06.19 Do effects on growth imply effects on reproduction?

true false
No, effects on reproduction can go without effects on growth.
Yes, a reduction of allocation to growth implies an increased allocation to reproduction due to conservation of energy.
Yes, a reduction of growth implies a reduction of feeding, and therefore a reduction of reproduction.
No, growth has nothing to do with reproduction.
No, many species only reproduce when fully grown.

06.20 Do effects on somatic maintenance costs imply effects on reproduction?

true false
No, because allocation to somatic maintenance is on the expense of that to growth not to reproduction.
No, maintenance has nothing to do with reproduction.
Yes, allocation to somatic maintenance directly competes with allocation to reproduction.

06.21 Do effects on feeding imply effects on reproduction?

true false
Yes, because effects on feeding imply effects on growth, and this directly effects reproduction.
No, feeding has nothing to do with reproduction.

06.22 Does food density modify toxic effects on reproduction?

true false
Not as long as food density is constant.
Yes, it always modifies toxic effects on reproduction.
It may modify effects on reproduction, but that depends on the mode of action.

06.23 How can you choose which mode of action is most appropriate in the analysis of data for effects on growth?

true false
You can test statistically which mode of action fitts better.
There is no objective way to do it, although one can look at the goodness of fit as indicator.
Check for which mode of action the standard deviation is smallest.
Check for which mode of action the (weighted) sum of squared deviations of data from model prediction is smallest.
One should measure quantities that identify the mode of action, such as feeding rate and respiration.

06.24 What is the definition of the EC50 for growth?

true false
The concentration at which growth of an individual is reduced by 50 percent?
The concentration at which growth of each individual is reduced by 50 percent?
The concentration at which average growth of all tested individuals is reduced by 50 percent?
Such a definition does not exist, because the growth rate changes in time.

06.25 Are effects on population size development always best characterized on the basis of the effects on growth rate, or on that on population size at a standardized exposure period?

true false
Yes, because population size depends on test conditions such as inoculum size and amounts of nutrients.
No, it depends on the mode of action.

06.26 Why does the aging parameter have the dimension of an acceleration?

true false
Because death rate by aging is proportional to something that accumulates after DNA damage.
Because aging is proportional to respiration, and respiration is proportional to squared length.
Because DNA repair decreases with time.

Chapter 07: Extensions of DEB models

07.01 Can substrate adaptation by bacteria be modelled in a DEB context?

true false
Yes, but we may need extra state variables.
Yes, we need rules for the change in the maximum specific uptake rate.
Yes, we need rules for the change in the saturation constant.
No, because {sc deb theory assumes a constant food composition.

07.02 When does a functional response appraoch the Holling Type I?

true false
Increasing the diffusion coefficient through a stagnant layer around the organism?
Limitation by a complementary compound when the limiting compound exceeds some threshold value?
Decreasing the thickness of the stagnant layer around an organism through which food or substrate has to diffuse?

07.03 Gut residence time depends on body size and feeding rate; yet digestion efficiency is taken to be constant. What factor gives more stringent constraints on the digestion process?

true false
Changing body size, because the ratio of gut surface area and volume changes in a way that gives high efficiencies for large sizes.
Changing food density, because high food intake rates go with poor digestion efficiencies.

07.04 Can effects of parasites be captured by changing the model's parameter values?

true false
Yes, but we need extra state variables to model the changes.
It is not necessary to change parameter values, some effects of parasites can be modelled without changes.
No, we need a different modelling approach to deal with effects of parasites.

07.05 Is the molar yield of microbial mass from a substrate proportional to the substrates' chemical potential at a fixed specific growth rate?

true false
Yes, because the max. specific assimilation power and the reserve capacity are proportional to substrates' chemical potential.
No, because dissipating heat increases with substrates' chemical potential.
No, because substrate is, besides energy source, also carbon source.

Chapter 08: Co-variation of par values

08.01 How would product formation scale with structural body mass among species of ectotherms?

true false
The scaling exponent equals 2/3, because assimilation scales this way.
The scaling exponent is somewhere between 2/3 and 1, because of the contribution of assimilation and maintenance.
The scaling exponent equals 1.

08.02 Why do scaling relationships in the literature relate many variables to body weight; what makes body weight special?

true false
Weight-specific relationships relate most easily to underlying molecular processes.
Weights are easy to measure.
Tradition; some authors started, others followed.
Body weight should be replaced by respiration, because this reflects the basic activity of life.

08.03 What is the difference between primary and secondary scaling relationships?

true false
Primary ones are more reliable than secondary ones.
Primary ones are more important than secondary ones.
Primary ones concern primary parameters, secondary ones functions of these parameters.

08.04 Why does respiration rate scale with body weight to the power around 3/4, both intra- and inter-specifically?

true false
Because this reflects a basic property of biomass, which is independent of the species.
Because the contribution of reserves increases with body weight, and reserves do not respire.
Because large-bodied species and individuals grow slower.

08.05 Why is the Von Bertalanffy growth rate for birds larger than for mammals?

true false
Birds are smaller than mammals.
Birds have a higher body temperature.
Birds do not have higher von Bertalanffy growth rates.

08.06 Why do incubation times increase with egg weight among species and decrease within a species?

true false
Because structural mass at hatching is a constant within a species and increases among species.
Because energy conductance is constant within a species and decreases among species.
Because the reserves at hatching increase with egg size within a species, and decrease among species.

08.07 How would respiration and the von Bertalanffy growth rate scale with body weight among species if the reserve capacity would be negligibly small?

true false
Reserve capacity would not affect the scaling relationships, so the exponent for respiration is about 3/4 and for the von Bertalanffy growth rate less than -1/3.
Reserve capacity would not affect respiration, only the von Bertalanffy growth rate.

08.08 Why is the specific assimilation rate proportional to max volumetric structural length?

true false
Because it fits empirical data.
Because it is an extensive parameter.
Because max. structural length further depends on (two) intensive parameters only.

Chapter 09: Living together

09.01 What is the difference between structured and non-structured population dynamics?

true false
The population reacts to environmental factors in a structured or a non-structured way.
The individuals behave identically in non-structured populations, and differently in structured ones.
The population consists of a single sub-population if it is non-structured, and of several sub-populations if it is structured.

09.02 Why does the specific growth rate of a population settle in a chemostat at the throughput rate in the long run?

true false
Organisms that grow at other rates are washed out.
It does so only for a special value of the substrate concentration in the supply.
It does so for a special value of the substrate concentration in the chemostat.
The mean specific growth rate over a very long time interval equals the throughput rate, not necessarily the value at a particular moment.

09.03 Can logistic growth in a batch culture be explained on the basis of the DEB theory?

true false
Yes, if the saturation coefficient and the specific maintenance costs are small, and the reserve capacity large.
Yes, if the reserve capacity and the specific maintenance costs are small, and the saturation coefficient is large.
No, logistic growth cannot be explained by the DEB theory.

09.04 What possible shapes can a stable age distribution have?

true false
Any shape that satisfies the conditions for a scaled frequency distribution.
It cannot increase for increasing age.
It can have a single maximum at some age larger than zero.

09.05 Is it possible to deduce the growth curve from the stable age and size distributions?

true false
Yes, if we also know the specific growth rate for reproducer population.
Yes, but we also need to know the size-specific probability rate for dividing in the case of dividers.
We can better measure the growth curve, if we want to know it.

09.06 Why do small specific growth rates increase with substrate relatively steeper for increasing reserve capacities?

true false
Because both substrate and reserves are used to grow.
Because it takes time to built up reserves, but once they have been build up, growth proceeds are a higher rate.
Because reserve increases with substrate concentration, which reduces growth, for which is compensated by considering relative specific growth.

09.07 Do reserves stabilize or destabilize population dynamics?

true false
They can stabilize, because peaks in food availability are hardly followed.
They can destabilize, because when a predator suppressed prey density to low levels, it can continue to suppress it even further by using its reserves.

09.08 What stabilizes the algae/polyp ratio in a coral?

true false
The polyps digest algae if they are too abundant.
The polyps confine the algae to certain body parts.
The polyps provide the algae with little nitrogen if they receive a lot of carbohydrates.

09.09 Why does the first offspring contribute more to population growth than later offspring?

true false
Because that offspring gets offspring earlier.
Because first offspring is stronger than later offspring.
Because it receives most parental care, later offspring has to share this care.

09.10 When can we expect chaotic behaviour of a population?

true false
When food density rapidly fluctuates.
When it loosely interacts with many other populations.
When parameter values satisfy certain constraints.

Chapter 10: Evalution

10.01 Did the single-reserve organism evolve from the multiple-reserves one?

true false
Yes, because uptake needs to be coupled for single-reserve organisms, which requires complex substrate types.
No, because multiple-reserve organisms are more complex than single reserve ones, and complex organisms evolved from simple ones.
No, these organisms evolved independently.

10.02 Does max reproduction increase in a new generation that switches from indeterminate to determinate growth, while keeping all other energetic aspects the same?

true false
Yes, because it starts to reproduce earlier.
No, because food intake relates to size, and the determinate organism stays smaller.

10.03 Did single-reserve systems evolve from multiple reserve systems or vice versa?

true false
Single reserve systems were first, because they are more simple.
Multiple reserve systems were first, because uptake of essential nutrients was orginally uncoupled.

Chapter 11: Evaluation

11.01 What is the difference between assimilation and net production models?

true false
There is no basic difference.
Net production models pay maintenance and reproduction costs from reserves, assimilation models from food.
Assimilation models work out assimilation processes in most detail, net production models give most attention to growth and reproduction.

11.02 What is the difference between Scope For Growth (SFG) models and Dynamic Energy Budget (DEB) models with respect to accounting for respiration?

true false
SFG models treat respiration as losses, DEB models include production overheads in respiration.
SFG models relate production to feeding minus faeces and respiration costs, DEB models allow production from reserves that have been built up in the past.
SFG models only deal with the organism as it is at a given moment, DEB models account for the full life history.

11.03 Do Static Energy Budget (SEB) models differ from Dynamic Energy Budget (DEB) models with respect to accounting for urinary energy?

true false
SEB models subtract urinary energy from food energy, DEB models add it to maintenance.
SEB as well as DEB models treat urinary energy similar as fecal energy.
DEB models do not take urinary energy into account.

11.04 What is the difference between energy allocated to growth, and energy fixed in new tissue?

true false
If we multiply the amount of new tissue with its chemical potential, we arrive at the energy allocated to growth.
Energy allocated to growth has a negative sign, energy fixed in new tissue has a positive one.
There must be a time difference, because energy has to allocated first, before it can be fixed.

11.05 Is logical consistency more important for models than realism?

true false
No, realism is more important because unrealistic models are worthless.
That depends how far model predictions deviate from reality.
Yes, consistency is more important because inconsistent models are worthless.

11.06 Can pure net production models handle reserves in a realistic way?

true false
Yes, why not?
Not in micro-organisms, because growth is their only production process, so why should they make reserves?
Not during starvation, when net production models should resemble assimilation models.
Not for embryos.

11.07 Why does ATP not play a significant role in DEBs?

true false
Because ATP turnover is too fast.
Because ATP stores a small amount of energy only.
Because few energy-related transformations involve ATP.

11.08 Why is it important for a model to be dimensionally correct?

true false
Else it will not fit data from experiments.
Else it will be of little help to understand the underlying processes.
Else we cannot inter- or extrapolate.
Else we cannot compare parameter values when the model is fitted to different data sets.

11.09 Why are allometric functions problematic?

true false
Because they rarely fit experimental data.
Because they have a large number of parameters.
Because we cannot compare their parameter values, when fitted to different data sets.
Because underlying mechanisms are unknown.
Because they are not widely known in the literature.
Because the reference value of the argument is arbitrary.
Because inter- and extrapolation is problematic.

Bas Kooijman

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