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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24
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1answer
6k views

Do insects' muscles become stronger with exercise?

I am curious to know if insect muscles become stronger with exercise, because I have seen many insects get tired out, but I have never seen one get stronger. They always seem to become permanently ...
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1answer
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 ...
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6answers
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Why do seeds grow upwards?

Why do seeds grow upwards? Surely gravity would pull them towards the earth's core? Can anyone shine any light on this? Do seeds that are planted deeper grow more quickly.
12
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2answers
278 views

Is there a favoured mathematical model of bacterial growth?

One of the most regularly measured phenotypes in bacterial synthetic biology is growth. Anyone who does wet lab microbiology or synthetic biology will have performed a growth curve measurement. ...
11
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2answers
255 views

Can you accelerate the growth of a plant by accelerating its surroundings?

I had this weird idea of making plants grow faster when I first visited an indoor nursery which used floodlights instead of sunlight. They turned on during the day and went off during night in cycles. ...
8
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2answers
567 views

What are the evolutionary reasons behind men being taller than women?

Human men and women are sexually dimorphic: there are some phenotypic differences between men and women. Men being taller than women is an accurate stereotype. Overall, men are on average 13 ...
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1answer
751 views

Biggest change in size from birth

Which mammal has the largest change in size from birth to fully grown percentage wise?
6
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1answer
2k views

Do people grow shorter as they age, how common is it, and what triggers it?

Is it true that people become gradually shorter as they age? If it is, is it more common in one gender than the other? And is it known what triggers this? (Considering that the "shortening" probably ...
6
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1answer
212 views

Total dark deprivation at day-neutral plants

First of all, I am not a biologist. Almost for a week, a question has come to my mind: "Is it harmful ceaselessly exposing a plant to light?" (I mean with natural & artificial light ...
6
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1answer
218 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. ...
6
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1answer
379 views

Trees growing around objects vs pushing them away. Where is the threshold?

If a tree grows against a taut wire then the tree will grow around it, eventually enveloping the entire wire. This often scars the tree, and if the wire is thick enough, it will interrupt nutrient ...
5
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3answers
1k 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 ...
5
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1answer
382 views

How do mushrooms react to being grown in a microgravity environment?

I'll use Agaricus Bisporus as an example mushroom. If cultured in potato dextrose yeast extract agar, will the resulting growth grow in a normal pattern? Will the sporocarps emerge from the surface (...
5
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2answers
2k views

If higher levels of atmospheric oxygen can lead to larger animals, can it also lead to larger plants?

According to some information, in the ancient past (at least some) animals grew larger due to a higher levels of oxygen in the atmosphere. So for example there is this study regarding dragonflies. ...
5
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1answer
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
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1answer
103 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 ...
5
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1answer
412 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
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1answer
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 ...
5
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1answer
255 views

Scale up of Bacterial growth from 250mL to 1-5L?

I am currently growing up a specific strain of E.Coli with a knockout in 40mL of growth medium (LB) in a 250mL shaker flask... My ultimate goal is to scale up this process to a 1-5L large scale setup ...
5
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1answer
309 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 ...
5
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1answer
296 views

With an excess supply of nutrients, in how much time will the number of algae cells double in full sun?

I am growing algae in a container in my roof. It gets sunlight for the whole day as there are no clouds nowadays in my area. There is no lack of nutrients as I am constantly adding water mixed with ...
5
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1answer
403 views

Can we artificially increase human growth using HGH?

Robert Pershing Wadlow was a man who lived in the first half of the twentieth century. He had hyperplasia of his pituitary gland, which caused him over-produce human growth hormone (HGH), and as a ...
5
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0answers
46 views

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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232 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) ...
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170 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 ...
4
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2answers
5k 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 ...
4
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1answer
358 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 ...
4
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3answers
121 views

What is the mechanism through which fractals arise in plants and animals?

Many biological organisms -- such as trees, broccoli, and the blood vessels in animals -- can be approximately described using fractals. What is the reason behind such fractals? Specifically, do we ...
4
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2answers
380 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 ...
4
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1answer
250 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?
4
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1answer
463 views

Why is DNA replication so much faster in prokaryotes than eukaryotes?

There are many statements to be found on the internet of the sort: “DNA replication occurs at elongation rates of about 500 nucleotides per second in bacteria and about 50 nucleotides per second in ...
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2answers
7k 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. ...
4
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1answer
4k 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 ...
4
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2answers
5k views

What is the fastest growing bacterium?

E. coli has a generation time of about 20 min, and a single CFU will generate a colony a few millimeters in diameter after 16 hours of incubation. Is this the upper limit? How much faster can ...
4
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1answer
314 views

What is the connection between exercise and muscle growth

From a physiological perspective, all that is done during exercise is the expending of energy in the form of ATP to fuel muscle contraction and extension. When I looked up why muscle grow due to ...
4
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1answer
46 views

Which C. elegans would be appropriate for general study?

Would wild type N2 be best or Dyp-11? I know they're different, but I just want to observe the worms to see life stages, movement, etc. Dyp-11 seems like it would be easy to see but N2 is the wild ...
4
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1answer
237 views

Mechanisms of bone growth

The length of a bone is caused by growth of hyaline cartilage which is then replaced by bone tissue. How do cells know whether they should grow the hyaline cartilage? What are the key molecules that ...
4
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2answers
95 views

What is the substance that tumors release that stimulates growth of blood vessels but suppresses its release from other tumors?

I'm currently in high school and I am working on a cancer research project. My project consists of a cancer, and different ways to treat it. I have a set of benign tumor and I was thinking of ...
4
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2answers
86 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 ...
4
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1answer
493 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 ...
4
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1answer
941 views

How does aging affect fingerprint?

Do fingerprints change as we grow from child to adult? Most notably, what is the effect of the increase in surface area of palms and fingers on the finger print? Does the finger print simply increases ...
4
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1answer
202 views

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?
3
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2answers
321 views

How do I determine this logistic growth model formula?

The Question Two yeast cells were placed into a special container to which food was continually added, to keep it at a constant concentration. All other factors were set for optimal yeast ...
3
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1answer
68k views

I'm 20. Can I still grow taller? [closed]

I'm 20, in about 6 months I turn 21. For some time I've been wondering whether there are natural, non-surgical and non-pharmaceutical ways that humans can continue to grow after reaching adulthood. ...
3
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1answer
448 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 ...
3
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1answer
355 views

Circulating factors affecting human health/longevity

Circulating factors present in young mice have been shown to promote rejuvenation of aged mice, suggesting that tissues have inherent capabilities to regenerate, and circulating factors may be ...
3
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1answer
7k 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 ...
3
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0answers
25 views

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 ...
3
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0answers
35 views

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 ...
3
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0answers
46 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 ...