Questions tagged [plant-physiology]
Study of the normal functioning of plants and plant cells
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Why aren't leaves black?
I s'pose this is a variant of the age-old question, "Why are leaves green?" It's fairly easy to ask teh internets and find plenty of answers for that one.
I have a different but related question: ...
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How many photosystems in a chloroplast?
I haven't been able to find any good order-of-magnitude estimates for how many photosystems (e.g. how many PSII complexes, how many PSI complexes) are in an average chloroplast (or perhaps per area of ...
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Explanation behind the observed chloroplasts in Elodea during Hypotonic vs Isotonic Solution
Me and my colleagues put the elodea leaf in distilled (hypotonic) and tap water (isotonic). We observed under the microscope that the elodea under the hypotonic solution became elongated and turgid, ...
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Why were vegetation coverages not assumed to be affected by precipitation, humidity or temperature?
I am trying to understand the graph topology of the structural equation model (SEM) given in Figure 1 of Bisset et al 2023. It is stated in the paper that it reflects an a priori causal structure.
I ...
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Do Glycosides in plant seeds serve some other function than protecting the seeds?
Many plants have toxins like glycosides in the seeds and I think other parts of the plant and the accepted reason for this I believe is to discourage animals that ingest the seeds from digesting ...
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What actually kills a plant that requires winter dormancy if it is kept indoors all year?
In bonsai practice, beginners will commonly purchase a juniper (often Juniperus procumbens 'Nana'), which is an outdoor tree, and keep it inside all year. The tree invariably dies. It is commonly ...
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Is infrared photosynthesis possible?
The post-apocalyptic science fiction novel Dark Universe by Daniel F. Galouye has some plants living inside bunkers that use infrared light for photosynthesis. There are speculations that ...
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optimal spatial arrangement (distribution) of plants
Microalgae are organisms that can grow in aquatic environments and use light and carbon dioxide (CO2) to create biomass. Research showed that Microalgae's biomass can be used as a bio-fertilizer.
My ...
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Database or model for plant nutrient requirements with respect to soil and climate?
Microalgae are organisms that can grow in aquatic environments and use light and carbon dioxide (CO2) to create biomass. Research showed that Microalgae biomass can be used as a bio-fertilizer.
My ...
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Do all plants have meristems?
Are there any plants that lack a meristem (at any phase in their lifecycle)?
Searching for it on the web, the materials I find seem to assume no, but none say it explicitly.
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Are there any genetically modified GMO squash with a vine growth habit which grow back from the root?
When I cut Scottish thistles with scissors, the thistle grows back from the tap root.
When I accidentally step on squash vines, the squash vine dies.
I was wondering if genetics research has produced ...
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Why do sieve elements need to be alive
I am studying high school biology and I got these two pieces of information in khan academy and wikipedia:
Sieve elements in phloem are living cells because the translocation includes active ...
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Do monoecious plants have bisexual flowers?
I used to think that monoecious plants have male (unisexual) flowers and female (unisexual) flowers on the same plant but on different locations. But recently I learnt that monoecious plants also have ...
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What is the nature of seedless fruits?
Can seedless fruit be produced in nature without humans interfering with the fruit? And would that be considered a spontaneous mutation?
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Induced mutation for fruit
If we induce a plant to be polyploidy would that affect other parts of the plant, for example when the plant produces a pollen grain would it still be (n) or would it be different?
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Which kind of inflorescence(s) does Sonchus oleraceus have?
Many capitulum inflorescences, several corymb inflorescences with capitulum inflorescences as the end nodes of each corymb inflorescence, or one compound corymb inflorescence with capitulum ...
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What determines the spiral direction of plants?
Some plants and vines spiral clockwise as they go along (right direction) and some spiral anticlockwise (left direction). What determines which direction they spiral along? At first, I believed it to ...
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What part, roughly, of the carbon in a plant comes from the soil? As opposed to the atmosphere?
C4 plants contain a slightly higher percentage of carbon-13 than C3 plants. Is this because of carbon obtained from the soil or the atmosphere?
I have read that plants using different chemical ...
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Sources of chlorophyll fluorescence
I have been reading this article recently, which claims that photoinhibition of photosystem II can have measurable impacts of chlorophyll fluorescence. This confused me, however, because ...
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Primary charge separation in Photosystem II
I was reading through an article about primary charge separation in Photosystem II when I came across the following graphic:
I assumed that the axis is measured with respect to the unexcited system, ...
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How do plants absorb CO2?
I see many repeated claims that plants absorb $CO_2$ from the air.
$CO_2$ goes into the stomata, while $H_2O$ evaporates and leaves those same stomata. The $CO_2$ dissolves in the water in the plant ...
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What is the use of having 3 antipodal cells and 2 synergids?
The embryo sac which is developed from functional megaspore contains 8 nuclei.2 polar nuclei and egg fuses with sperms.3 antipodal cells and 2 synergids degenerate after fertilization.Then what is the ...
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Is a plant's own compost better for the plant?
Does it make a difference if a plant is composted and used for its own compost ?
Meaning, let's say there is a plant "X" (example Cucumber)
Would it grow better if the compost was made from ...
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Explanation of the results of Warburg's Flashing Light experiment?
Between 1919 and 1920† Warburg obtained a higher rate of photosynthesis in Chlorella, exposed to rapid alternating periods of light and darkness, than when exposed to constant illumination. I would ...
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Does lower stomatal conductance of water influenced by elevated CO2 decrease overall evapotranspiration?
From what I understand, elevated CO2 levels decrease the stomatal conductance of water in plants. What I remember from irrigation sciences, higher temperatures should be more demanding on ...
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Why do highland/alpine plants require a drop in night temperatures to thrive?
There are mountain plants which require a drop in nightly temperature (many Nepenthes, Heliamphora and orchids for example). A non-specialist explanation is that the plants die of "starvation&...
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Caudex vs Xylopodium difference
I live in Brazil and many plants from the brazilian grasslands/prairies exhibit an structure called, by the brazilian literature, "xylopodium" (or "xilopódio" in portuguese) - ...
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Plants without bacteria? is it theoretically possible?
I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...
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Are fairy rings documented as a growth pattern in ferns?
I planted an Onoclea sensibilis, a single plant, in my garden. After the first season, there was signs that a fairy ring was forming. A few years later it was mostly complete, but then was obscured in ...
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How low potassium can potatoes have due to low potassium in soil?
According to Wikipedia 100 grams of potatoes has 2005 milligrams of potassium.
But if there is low potassium in the soil where it grows, it may not be able to acquire so much potassium.
How little of ...
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What are the most intelligent plants?
For intelligence lets adapt the definition from here:
Perception of the surrounding environment
Adaptation to environmental conditions
Communication (in the case of plants, through chemical ...
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In traditional plant cloning, why do we require two different vectors (plasmids)?
So I was recently taught cloning in plants and I came to wonder what is the need to first put the gene of interest in the entry vector plasmid and then the final vector plasmid before finally ...
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How does a tree trunk sprout and grow after being cut?
After I cut trees into logs and remove the branches in winter, they start growing. They sprout out and grow completely normal looking stems and leaves and maintain them all summer. The sprouts mostly ...
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Why do cucurbits produce so much fluid when their stems are cut?
When carrying out some germination tests on species in the Cucurbitaceae, I notice that young plants of this family produce a lot of clear fluid when they are dissected. Most plants I dissect do not ...
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Is there always a leaf(s) attatched to an auxillary bud?
I'm trying to create a 3D functional-structural plant model and I need to establish some axioms.
Is it guaranteed or extremely likely that where auxiliary bud forms there's a leaf(s) attached? That's ...
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Why do fruits have to ripen?
It seems like most fruits that we consume undergo some sort of ripening process either before or after they are picked from the vine, tree, etc. I understand that sugars are released during the ...
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Photolysis of water
Photolysis of water releases $\text{O}_2$, $\text{H}^+$ ions and $\text{e}^-$.
$\text{Mn}$ in the $\text{O}_2$ evolving complex also produces $\text{e}^-$.
What provides $\text{e}^-$ to P680:$\text{Mn}...
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Is it scientifically sound to pool repeated measurements?
I am measuring specific phenolic compounds in leaves of A. thaliana. I have many different varieties, and different treatments. Initially I was measuring one leaf per plant for three plants for each ...
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Is that true that plant stem cells can be used in humans?
I was reading an article (which seems very fake to me) on sensitive topics, but there was one astonishing statement:
Stem cells are obtained from certain plants that grow all over the world. Once ...
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scientific reasons behind a a sudden yet temporary growth sprout of the plant when the soil has No depth?
Sorry, I'm kind of naive when it comes to plant biology.
Mark 4:5-6( New American Standard Bible 1995 )
5 Other seed fell on the rocky ground where it did not have much soil;
and immediately it ...
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Difference between "biotroph" and "parasitic"
In the studying process for my exam I learned about ways of life of pathogenes in plants. There, it was mentioned, they can live nekrotrophic, hemibiotrophic or biotrophic.
As far as I understand, a ...
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Stomata during night (respiration)
How does carbon dioxide from respiration diffuse out of the leaf during the night?
Do stomata close completely during night?
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Is it normal for corn to have multiple ears in one place?
I have (out of a mistake) one corn plant in my greenhouse and it made 4 cobs in one place. Is that normal?! I never saw something like this before.
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Calculation of solute, pressure and water potential
What would be the water potential (Ψw), solute potential (Ψs) and pressure potential (Ψp) at equilibrium when a cell with Ψs= – 0.7 MPa and Ψp= 0.7 MPa is placed in a solution with Ψs= – 0.5 MPa? (...
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Measuring a plant's electric activity any instructions where to place electrodes?
I would like to measure a plant's electric activity / voltage, I've looked online to find out where to place the electrodes and what type of electrodes to use but they seem to very wildly. Any ideas?
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How long can zooxanthellae survive on their own, after being expelled from coral after a bleaching event?
So many sites (and books and journals and such) discuss how long different types of coral can survive without their dinoflagellate algae (zooxanthellae), but...
How long can the poor little symbiotic ...
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How much sunlight is required for photosynthesis to peak?
I've read that photosynthesis peaks at some point over light intensities https://en.wikipedia.org/wiki/PI_curve According to https://www.bbc.co.uk/bitesize/guides/z9pjrwx/revision/5 suggests
At very ...
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Issues obtaining Fo in DIY Imaging Fluorometer
I have successfully built an imaging fluorometer at home (see project details here) and so far is working amazingly well.
But I am having serious issues in obtaining Fo to calculate Fv/Fm (Fm-Fo)/Fm. ...
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What is the limiting factor for algal growth in the oceans?
As far as I can tell, pelagic algae require four main things to live: sunlight, carbon dioxide, trace minerals and physical space. What is the limiting factor?
Note this is kind of a deceptive ...
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vitamin D in mushrooms
How could I test vitamin D levels in mushrooms? (I am a high school student, our lab is pretty modern, but my resources are limited)
I found an article about it (https://www.hindawi.com/journals/jfq/...
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