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.
123
questions
1
vote
0
answers
61
views
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.
1
vote
0
answers
13
views
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 – ...
4
votes
2
answers
96
views
Breeding mosquitoes at lower temperature
It is well known fact that, to slow down the growth of drosophila, they are grown at 18-19 degree Celsius. It helps in maintaining stocks for longer time without frequent change of food. Is it ...
2
votes
0
answers
63
views
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, ...
1
vote
1
answer
2k
views
How do trees grow?
A nail is inserted into a tree's trunk at a young stage of its development. At which height will we find the nail after some years? Will it be found higher or at the same height(What extent of ...
0
votes
1
answer
82
views
The actual name of growth force
I see how large trees and weeds that are capable of splitting concrete, and realized that I have no idea what this phenomenon is officially called. Google was no help, suggesting root pressure, but ...
2
votes
1
answer
4k
views
Why do cherries sometimes grow as triplets?
Usually when I think of cherries, I think of them as pairs. I think most of us imagine them that way, but recently, I stumbled on a picture of a triple cherry:
Which I found interesting, but I couldn'...
2
votes
0
answers
33
views
Are nastic responses growth responses?
I know they are non directional movement responses, but like tropic responses, does their movement involve growth?
0
votes
0
answers
694
views
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 ...
3
votes
1
answer
474
views
What types of plants are Gibberellin used on?
On what type of plant (monocot/ eudicot? family? species?) is Gibberellin used on?
I searched through many sources but could not find whether Gibberellin works for all plants or just a specific type ...
1
vote
0
answers
372
views
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 ...
5
votes
1
answer
2k
views
Do brain cells regenerate in the adult brain?
I know that most cells in the body regenerate, dying and being replaced with new cells. For example, in bone special enzymes move radially outward from the marrow in a narrow tunnel, destroying the ...
5
votes
0
answers
265
views
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) ...
2
votes
1
answer
9k
views
what is the difference between pituitary dwarfism and thyroid dwarfism? [closed]
My book (Comprehensive Biology class XI, by J P Sharma ) mentions of two kinds of dwarfism- "Pituitary Dwarfism" and "Thyroid Dwarfism" but does not provide any details about the matter. so please ...
5
votes
1
answer
113
views
Database of cancer cells
I am looking for a database(or any kind of information source) of cancer cells, which has information about the speed of reproduction of these cells, how fast they grow, etc.
So I could make my ...
4
votes
2
answers
6k
views
Effect of transpiration on plant growth
It is said that only about 1-5% of water used by plants is used in photosynthesis while the rest is transpired. Suppose that a plant grows in an environment where the temperature is not too high but ...
-2
votes
1
answer
674
views
What is the maximum height of a tree?
I know there exists a huge variation in the height of trees. But what is the maximum height a tree can reach?
It must have something to do with the ability of the capillaries to transport life fluids ...
1
vote
1
answer
178
views
Why is it desirable to couple chemical production to growth?
I have the following question in systems biology:
a) Draw a graph showing the relationship of growth (Vbio) and Vefni for the system here. (Let the horizontal axis represent Vbio and the vertical axis ...
1
vote
0
answers
106
views
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, ...
5
votes
1
answer
330
views
Do young children grow in spurts
It is a commonplace of my friends and relatives to remark that a young child (younger than 3 years) has had a recent "growth spurt". The underlying assumption is that young children do not grow taller ...
8
votes
1
answer
1k
views
Biggest change in size from birth
Which mammal has the largest change in size from birth to fully grown percentage wise?
3
votes
1
answer
708
views
Plant growth in blue light
For the past two weeks, I have been in a group of 3 studying how different lights affect plant growth. So we growth two chickpeas plants and put one in white light and the other in blue light.
These ...
0
votes
1
answer
253
views
Why does hair know when it needs to stop to grow [duplicate]
I'm still not quite sure if head hair grows endlessly, or if it stops at some point, but that's not the question.
When the hair on my leg grows, it obviously doesn't grow endlessly, but it also stops ...
1
vote
1
answer
124
views
Measuring optical density with/without re-suspending cells
When measuring absorbance using a plate reader, is it necessary (or better) to resuspend the culture if the plate has been sitting still for 1-2 days?
While this could be a good physics question, I ...
2
votes
1
answer
676
views
Does the process of photosynthesis occur in insectivorous plants? [closed]
Does the process of photosynthesis occur in insectivorous plants?
Can you please give me a clear answer and explain to me how?
and also can you describe the environment in which they grow ?
Thank you
4
votes
2
answers
9k
views
Do trees grow from the bottom or the top, or is that oversimplifying?
I was wondering how trees grow. I wonder if it was similar to hair growth which occurs from the follicle. but clearly branches grow from the trunk so there is definitely a difference with hair growth.
...
2
votes
1
answer
399
views
Can growth rate be used as an indicator of fitness in fish populations?
I would like to calculate selection gradients in order to gain insight into the strength and type of selection influencing my study population.
(see here for review. http://jgking.web.unc.edu/files/...
1
vote
0
answers
644
views
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 ...
4
votes
2
answers
467
views
Modeling population growth - Variance
I've been studing population growth models, but there's something I can not find that's fustrating. That's a formula for the variance in population growth. I know that other models can be aplied, but ...
2
votes
0
answers
21
views
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 ...
2
votes
0
answers
882
views
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 ...
6
votes
1
answer
256
views
Is this some sort of fungus?
There is something strange growing straight out of the glass windows at work. They look like hairs, about half an inch long, and each have a white spot on the tip of them, slightly weighing them down. ...
2
votes
1
answer
2k
views
How are some people able to continue growing after reaching maturity?
This is technically a cross-post of a question posted last year concerning gigantism and how certain people are able to grow far past expectations after it's assumed they've reached maturity.
How are ...
3
votes
0
answers
49
views
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 ...
4
votes
1
answer
261
views
Are thunder and lightning necessary for any organisms?
Comparatively irregular events such as forest fires are necessary for some plants to grow (see here).
But do any plant or animal species have similar dependence on thunder and/or lightning?
5
votes
3
answers
2k
views
Exponential growth equation and bacteria
I'm a microbiologist, but I'm teaching some ecology in my intro-level course, so when we got to population growth, I thought I'd use the example of a microbial population. But, I hit a strange problem ...
1
vote
2
answers
1k
views
At what age does the mouse skull stop growing?
Unless otherwise mandated, neuroscientific research on mice is done with ~7-week old animals. There is a sort-of mantra that at this age their skulls stop growing.
However, recently, I noticed a ...
16
votes
1
answer
1k
views
Are the bacteria in the stomachs of unborn babies beneficial?
Babies are born with bacteria in their stomachs. I heard on The radio that when a child is given antibiotics for the first time unique bacteria in the stomach are destroyed and cannot be replaced. Is ...
4
votes
1
answer
8k
views
Are Young Girls Stronger than Young Boys?
According to "common wisdom" the average man has, as a proportion of his body weight, 50% more muscle mass than the average woman. This is in addition to how the average man is several inches taller ...
2
votes
1
answer
73
views
The properties of benign tumours
Do benign tumours have no functioning apoptosis mechanisms ? If so what stops benign tumours from excessive growth? Also can a benign tumour have a functioning apoptosis mechanism?
5
votes
1
answer
428
views
How does a seed determine when to start germination?
I'm sure there are many different ways for seeds of different species, but what is a general rule? Is it some kind of ideal temperature & wetness that triggers a chemical reaction? What factors ...
5
votes
0
answers
176
views
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 ...
8
votes
2
answers
1k
views
Does the bending of a tree's trunk in the wind stimulate and strengthen root growth?
Recently Southern California experienced extreme wind velocities and afterwards the news reported over 300 trees had fallen in San Diego County. I had either heard or read somewhere that the action of ...
1
vote
0
answers
102
views
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{...
4
votes
1
answer
5k
views
Which algae grow fastest under optimal conditions?
I'm interested in what the fastest growing microalgae are under optimal conditions for photoautotrophic growth (energy from photosynthesis only). Fastest can be interpreted as either shortest ...
2
votes
1
answer
5k
views
How to measure growth of algae with colorimeter
I am doing an lab for IB Bio and don't know how to use a colorimeter to measure growth in algae. The experiment I am doing will measure the effect of pH on algae growth. The algae will be taken from a ...
4
votes
1
answer
399
views
Why are cancer rates low in large animals?
Large animals generally have more cells and live longer than smaller animals. For example, bowhead whales live up to 200 years and weigh up to 100 tonnes, as opposed to humans (living ~71 years and ...
1
vote
0
answers
905
views
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 ...
3
votes
0
answers
553
views
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 ...
1
vote
0
answers
151
views
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?
...