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The growth of the yeast can be studied with a Logistic model (i.e. differential equation) as follows: $$ \frac{dX}{dt}=\mu X \left(1 - \frac{X}{X_{max}} \right) $$ This is an ordinary differential equation that tells you how the population of yeast is changing with time (in fact is telling you how the concentration of Yeast $X$ changes with time). The two ...


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The difference in DNA replication rate between prokaryotes and eukaryotes is still under current research, but the basics are understood. It is very much a matter of complexity, as eukaryotes are more complex in many different ways. I found a very useful reference for this and other kinds of related questions. Briefly, some possible reasons: [...] in ...


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Some clarifications: Commonly used models for bacterial isothermal growth curves (which represent the growth curve directly) are for example: Exponential Logistic Generalized logistic The Monod equation expresses how the growth rate changes with the availability of substrate see a related question here. The Monod equation can be incorporated into an ...


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the more biologically grounded Monod growth Why is the Monod model more biologically grounded? It is empiric and NOT based on biological considerations! I only know this equation from enzyme kinetics, not for cell-growth, where the identical Michaelis–Menten equation assumes a random collusion model. So according to this model, your cells would grow more, ...


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For the logistic equation, $$\frac{\mathrm{d}N(t)}{\mathrm{d}t} = rN(t)\left(\frac{K - N(t)}{K}\right)$$ the solution that allows you to calculate population population size at any time is: $$N(t) = \frac{N(0)Ke^{rt}}{K - N(0) + N(0)e^{rt}}.$$ Looking at this equation algebraically with a set of knowns—$K$, $t$, and $N(t)$—and a set of unknowns—$r$ and $N(0)$...


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because fractals are emergent structures created by simple rules, as are many biological structures. The same kind of simple recursive signals that lead to fractals are simple enough to be stumbled on by biological evolution and are effective ways to deal with the scaling problems created by the square cube law. https://www.complexityexplorer.org/system/...


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The answer is that they will do either or both, depending on conditions: this is one of the things that has caused complex systems scientists to be so interested in things like using slime molds in modeling optimization problems. In good nutritional conditions, the cells will happily multiply. At the same time, they will flow and reshape themselves to spread ...


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According to https://en.wikipedia.org/wiki/Human_hair_growth: Scalp hair is known to grow between 0.6cm and 3.36cm per month. The growth rate of scalp hair somewhat depends on age (hair tends to grow more slowly with age), sex, and ethnicity. It was previously thought that Caucasian hair grew more quickly than Asian hair and that the growth rate of women's ...


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You could place part of the mould into a cut in a piece of citrus fruit to continue its growth. Citrus can also host P. italicum, the below website is one mentioning how to differentiate between them. http://www.pestnet.org/fact_sheets/citrus_storage_moulds_197.html Hazards. Aspergillosis: (fungal spores growing in the lungs) which is uncommon. Asthma: ...


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Essentially, eukariote cells use internal and external signalling hormones, so the cells can have a front/back/top/bottom end and can orient themselves at specific angles using signalling hormones, which also travel outwards through chains of cells and form signalling hormone concentration gradients. Eventually, when the gradient reaches a certain level, it ...


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This answer might not completely answer your question, since this just explains the case in humans, but I think you can give this a read while waiting for a more accurate one. I would recommend you to read this amazing paper. Generally, across animal species, the longer it takes an organism to reach maturity, the longer it lives. How the timing of onset of ...


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Since you asked for the science I'll try to give a scientific but simple explanation. Trees (and plants) become wider and taller over time. This growth is due to cell division and cell elongation from meristematic cells (analog to stem cells in animals). The stem (upper part of a plant) becomes wider because is it constantly creating new vascular tissue from ...


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You can put any media in a GasPak or other anaerobic system depending the type of anaerobic growth you are looking for. Sometimes blood is simply added to media to meet nutritional requirements of an organism. I use Columbia Blood agar often as a general purpose anaerobic medium. In a collection of 100+ obligate anaerobes I am working with, around half grow ...


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