Questions tagged [growth]
In reference to a biological system over time, growth refers to the increase in physical size/mass as well as the progression through its life cycle.
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Why does eyebrow growth stop after it reaches a specific length?
When compared to hair that grows forever after we cut it, why do eyebrows stop growing? What genes measure current length of eyebrow to ensure it stops growing after a specific length?
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Make plant experience 2 growing seasons per year by moving it across equator semiyearly
If I take a typical plant (such as e.g. a rosemary plant or an avocado sapling) across the equator from Florida to Brazil and back every year, so that the plant experiences Spring in both places, will ...
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What's the difference between proliferation and diffusion when talking about changes in tumor density?
Cell proliferation and cell diffusion seem to be important quantities to estimate when trying to understand or measure tumor growth, but I don't really understand a) the difference between them or b) ...
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Escaping resource limitations during tumor evolution
In their discussion of the importance of r- and K-selection on tumors, Aktipis et al. (2013; figure 3) provide the following illustration of a hypothetical cancer growth curve:
In it, you can see ...
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Do babies have a fight or flight response?
Do babies react in the same way as young children and adults in regards to the fight or flight response? If they do not respond in a similar way or don't have a fight or flight response at all then at ...
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What to do with this Araucaria sprout
I live in Santiago, Chile, and I see this Araucaria frequently:
For what I have read, it seems to be a female A. angustifolia individual (leaves are 2-3 cm long and a few mm wide, with a very sharp ...
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Is there a law that defines an upper bound for the speed of growth of an organism?
I was wondering if there is some biological law (or chemical/physical law for that matter) that limits how fast an organism can grow.
I know that the growth of a plant is often restricted by the ...
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Cause-and-effect questions about growth and development of plant
I need to solve some cause-and-effect problems. The problems are related to growth and development of plant. "Growth and Development" chapter is the first chapter in third level of high ...
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Archenteron vs Gastrocoele
What is Difference between “Archenteron” and “Gastrocoele”.
Are they same or different?
Gastrula is characterized by Archenteron or Gastrocoele or Both?
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due to hypersecretion of growth hormone why only terminal growth takes place?
why only terminal growth takes place in acromegaly and gagiantism, due hypersecretion of GH?
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Is an animal's body height dependent on its environment?
Imagine the follwing situation: a newly born animal is brought into a small room. This room has no windows, but artifical light to imitate the sunlight. Furthermore, this light behaves like the sun, ...
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Are nastic responses growth responses?
I know they are non directional movement responses, but like tropic responses, does their movement involve growth?
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Growth of Axons
Does anybody know a paper in which the growth of axons, i. e. their length in dependence of time was measured? I did some literature mining myself, but couldn' t find any results.
I'm looking for a ...
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Prevent clumping of bacteria in my media so that I can measure turbidity?
Forgive my naivety, I'm an undergraduate Chemical Engineering student doing research this summer into growth rates of various combinations of bacterial isolates.
I have about 9 isolates from a toxic ...
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Is it possible to simulate the effects of high altitudes for plants?
Note- I considered asking this on gardening.stackexchange.com but i believe it is better suited for this site since it deals with more complicated material.
As I understand it, certain plants (...
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Genetically improved *Leucaena leucocephala* seeds
I am looking for fast growing Leucaena leucocephala seeds. Now, I am cultivating Leucaena leucocephala which can grow 6 meters in a year. But I am looking for a genetically improved seed which can ...
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Reasons behind the sticky substances are used by poplar in buds
It is well known that sticky poplar buds falling on a car can seriously damage the paint. Also these scales from poplar stick to the paws and fur of animals like Velcro. Personally I don’t think the ...
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Beyond anabolism, what are factors that restrict growth rate?
Beyond obvious constraints in the case of nutrient limitation, what can explain the relatively slow growth rate of cells in rich media?
Lab strains of E. coli grow really, really fast. The cell ...
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Does a cell deprived of growth factors undergo apoptosis or G0 stasis?
I can't seem to find a decisive answer on this topic in any of my textbooks. If a cell is deprived of growth factors does it:
Activate apoptosis
Go into the G0 phase but keep living?
Thanks.
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Selective pressure for reduced rates of growth and maturity in primates
Humans are somewhat notable for the slow rate at which they grow and reach physical maturity. Some related primates also take over a decade to reach sexual maturity.
However, many mammals – ...
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What determines when plants grow?
I am interested in dryland ecosystems, and I am trying to find material on what determines the time at which plants in dryland ecosystems, either shrubs or grasses, grow and shoot? Is it only related ...
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What makes delayed onset muscle soreness stop occurring?
If someone lifts weights or takes a long jog after not doing it for a while, they can experience delayed onset muscle soreness (DOMS).
However, when they return to the same exercise days afterwards, ...
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Wet weight measurements: Setting up cultures for measuring growth rate via wet weight
I have some isolates which I am trying to grow in some toxic leachate in order to measure their growth rate I also want to measure the growth rates of certain combinations of these bacteria.
I've ...
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Values of Miu_max and Ks from parameter estimation?
Background
I have this simple biomass growth model:
$$
\mu = \mu_{max}\cdot \left(\frac{S}{K_S+S}\right) \cdot \left(\frac{1}{1+S/K_{iS}}\right) \cdot \left(\frac{K_{iP}}{K_{iP}+P}\right) \\
\frac{...
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Why is it easy to separate the cotton wool from the roots of young plants grown in cotton?
In my book it is said that if we grow Maize and Gram seeds in wet cotton, after the seeds are sprouted it is easy to separate the cotton wool from the roots of young plants.
My question is why is it ...
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Which of these methods is both effective and reliable in elongate muscle and tendon for use in humans: growth factors or stem cell technology
Which method is it the most effective, but also the most reliable for elongating muscle and tendons for clinical trial; using modern growth factor technology or using modern stem cell technology?
...
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Calculating the canopy size (crown) of a newly planted tree at a future date
Assuming that one knows the maximum area of the canopy and the age of the tree when it achieves this. And given an initial canopy size from the nursery. How would I calculate the canopy size at a ...
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Does Acromegaly cause actual expansion of the zygomatic(cheek) bone
Acromegaly is a disorder in adults involving excess growth hormone production. Since epiphyseal fusion has already taken place in most bones of adults , this does not cause an increase in stature. ...
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Giant insects growing question
During the dinosaurs time 100-200 million years ago there were giant insects like 1 meter long. An example is here. One of the theories why they could grow this big is that oxygen level was much ...
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What would be the growth rate in the following scenario
In my textbook the exponential growth rate is described as
W'= W e^rt
Here W' is the final size, W initial size, r growth rate and t time.
I wanted to have a clear mathematical understanding. So far ...
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When do growth curves "reach maximum"?
I have been reading about growth curves, specifically those with upper and lower asymptotes, which have been asked about here before. See also Tjørve & Tjørve (2017).
In these models, is there a ...
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How do I grow 5 liters of purple non-sulfur bacteria?
I am running experiments for a project that requires large amounts of purple non-sulfur, Cyanobacteria and nitrogen fixing bacteria. I plan on growing all the species in separate tanks. The species' I ...
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Auxin-what happens to the auxin chemicals if the Sun is just above the plant?
The Auxins goes to the shady side for the elongation of the cell. This moves depending on the direction of sunlight. But, what happens to the auxin chemicals if the Sun is just above the plant?
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The animal with the fastest hair growing rate
we know that human hair usually grows about 1/2 inch a month.
My question is what is the species with the fastest hair growing rate? (including fur for example).
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Is any animal born adult-size?
Size growth after birth seems to be the norm in the animal kingdom (as well as among plants). This makes sense. It's evidently physically challenging for an animal to produce an offspring of its equal ...
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Alternative to Lotka Volterra
Would you guys know any kind of differential equations that would dictate population growth without relying on Lotka Volterra ? Thanks ^^
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Age until physical growth ceases, mammals
Fairly basic, but I am seeking a table showing how many years from birth it takes for the best-known mammals to stop growing. (Including the latest on humans - ie. 0-17..?).
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Per Capita Population Growth Rate and Exponential Growth. Rate constants
As many of us might know, the set up of a differential equation relating instantaneous population growth with respect to time to the per capita population growth rate and current population size at an ...
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What do bones need to grow outside the body?
In what environment outside of a living organism can bones grow?
If I were to put an arbitrary human bone in a room and attach a bunch of tubes to it, or dunk it in some kind of solution, where would ...
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Do all body organs grow in proportion during the period of physical development?
It is obvious that during childhood and puberty, the human body grows uniformly or proportionally so that a child's arm length, for example, is shorter than an adult's arm length but is proportional ...