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57

Good question. If you look at the spectral energy distribution in the accepted answer here, we see that photons with wavelengths less than ~300 nm are absorbed by species such as ozone. Much beyond 750 infrared radiation is largely absorbed by species such as water and carbon dioxide. Therefore the vast majority of solar photons reaching the surface have ...


38

Surely it would be even more beneficial for plants to be black instead of red or green, from an energy absorption point of view. And Solar cells are indeed pretty dark. But, as Rory indicated, higher energy photons will only produce heat. This is because the chemical reactions powered by photosynthesis require only a certain amount of energy, and any ...


25

The short answer is that as long as the vegetable/fruit is fresh looking - i.e. the cells have not disintegrated - they will be respiring, many cells will be functioning quite normally, and the plant is still technically alive. In cases where the part of the plant we treat as a vegetable is a part intended for reproduction (e.g. a seed, or a tuber like a ...


22

In fact, the idea of a plant nervous system is quite serious and constantly developing; of course those are rather local, simple signal pathways rather than an "animalian" centralized global network, but they use similar mechanisms -- depolarisation waves, neurotransmitter-like compounds, specialized cells... Here is a review paper by Brenner et al. In the ...


21

Cellular respiration in plants is slightly different than in other eukaryotes because the electron transport chain contains an additional enzyme called Alternative Oxidase (AOX). AOX takes some electrons out of the pathway prematurely - basically the energy is used to generate heat instead of ATP. The exact purpose of AOX in plants is still unclear. Plants ...


21

The vast majority of a tree's carbon comes from the air, which averages 0.03-0.04% by volume (300-400 ppmv) CO2. This is fixed through photosynthesis and eventually stored as glucose which the plant can then use for its metabolism. Doing some quick math, this means that in order to produce 1 kilogram of carbohydrates (e.g. cellulose) a plant needs to ...


18

The short answer is that corn genome is large and has a huge amount of duplication events. Around 80% of the genome are repeated. It's hard to assemble genomes with large amount of duplications because our sequencing technology, practically, at best can give ~500 base pairs. Figuring out the ordering of duplicated regions relies on scaffold sequences or ...


18

I believe it is because of a trade off between absorbing a wide range of photons and not absorbing too much heat. Certainly this is a reason why leaves are not black - the enzymes in photosynthesis as it stands would be denatured by the excess heat that would be gained. This may go some of the way towards explaining why green is reflected rather than red ...


18

See this paper "Divergence time estimates for the early history of animal phyla and the origin of plants, animals and fungi" for information on the divergence estimates (I'm not sure if there are more recent papers discussing this). Plants, animals and fungi are eukaryotes, distinct from eubacteria and archaebacteria, which are prokaryotes. The difference ...


15

I've been doing some reading, and have come up with the following interesting information. Telomeres During cell division the DNA is replicated, but the mechanism is imperfect and in each round of cell division a small section is lost from the end of each chromosome. To compensate and protect the genetic information there are caps – regions of excess ...


13

There are several key ways in which rising atmospheric CO2 concentrations will affect photosynthesis, and these are related to the different types of photosynthesis. In order to properly answer your question, I'll provide some background about photosynthesis itself. Photosynthesis evolved in a high-CO2 atmosphere, before the oxygen-enrichment of the ...


13

It depends how you define locomotion. If you take it to mean moving from one place to another, then yes, almost all plants do this at some stage during their life cycle. Primarily seeds and pollen move around, and generally they do so by harnessing either natural forces like wind and rain, or by manipulating animals to do the leg-work, e.g.: by recruiting ...


13

I like your question! Low surface pressure on Mars (averaging 600 Pa or about 1/170 of Earth's at sea level) is only one difficulty that an organism would have to contend with. In addition, mean surface temperatures are ~210 K (-63 C), the surface ultraviolet flux is extremely high (no ozone layer) and an aridity comparable to the Atacama desert. On the ...


13

There are some other good answers which provide part of the picture, but I think there is a fundamental organising principle which has been missed. Konrad has touched on it in his answer. The reason trees, and most plants, tend to grow equally in all directions is that they have iteratively generated branching and radial symmetry which is controlled in a ...


13

While poison affects not every organism equally, plants did develop some poisons to avoid being eaten. However, if you look at the great multitude of so-called secondary metabolites, most of them are poisonous to either viruses, bacteria, fungi or other microorganisms, or insects, or even other plants. Plant evolution just hasn't had time to adapt to humans. ...


13

Yeast are neither plants nor animals; they are fungi. The old classification where things were lumped into only two buckets - plants or animals - has long since broken down. In fact, even things you might think of as plants, like algae or most seaweed are no longer classified as plants. Under the old system, plants and animals were considered kingdoms, and ...


13

The more "dangerous" properties of spicy peppers are chiefly due to capsaicin. Sigma-Aldrich sells purified capsaicin, for which they provide safety information, including an MSDS. Most of it is the usual, unsurprising set of warnings about irritation to eyes and the respiratory system. However, there are LD50 numbers: LD50 Oral - rat - male - 161.2 ...


12

Thanks for asking an interesting question which made me think. The short answer is that something evolves if there is an advantage to the genes involved, and, by 'advantage' I mean it produces more copies of the genes in the next generation so more individuals with that characteristic will be present in the population. As to what particular advantage ...


12

It's probably Arbutus unedo, strawberry tree. Native to Mediterranean region and some part of western Ireland. Edit: I've just spot that you found it in California, so it's probably one of north american Arbutus species, eg. Arbutus menziesii.


11

I wanted to add a little more to the excellent answer above, especially since the OP asks about research into this question in a "real-world context". There is a substantial body of evidence on exactly this question that comes from experiments at "Free Air CO2 Enrichment" (FACE) sites. FACE is an experimental method/technology in which standing ecosystems ...


11

I'd like to add to Amy's excellent answer. Generally, galls are induced by the forced accumulation of plant hormones at different levels to those naturally maintained by the plant, in a localised area. Usually the hormones targeted are auxins and cytokinins which are both involved in the regulation of normal growth patterns; disrupting these patterns leads ...


11

Haswell, Peyronnet, et al (2008) have shown that plants have some of the same mechanosensitive ion channels that E. coli does. The work was on the roots of Arabidopsis and not the plant you are investigating, but the mechanism could be similar. It would not seem that vibration plays a role, as it the plant seems responsive to the touch of the human rather ...


11

Some additional notes- I have grown TickleMe Plants (sensitive plants) for years and I have seen the plants close their leaves as a reaction to the vibrations caused by my foot steps as well as blowing on the plant and placing the plant in cold, very hot and dark environments. In addition I have found the plant's ablity to detect vibrations I have observed ...


11

I'm surprised nobody has mentioned Jan van Helmont. To summarise Blankenship's account, in the 17th century, he (Helmont, not Blankenship) grew a tree in a known dry weight of soil and weighed the fallen leaves of the tree, and then eventually the whole tree including the root system. He found that the mass of the soil had barely diminished and concluded ...


10

There is quite a fun article here which discusses the colours of hypothetical plants on planets around other stars. Stars are classified by their spectral type which is dictated by their surface temperatures. The Sun's is relatively hot, and it's spectral energy distribution peaks in the green region of the spectrum. However the majority of stars in the ...


10

In flowering plants (the angiosperms) there are several developmental transitions in the life of the plant. I won't list the plants, because the list includes pretty much all of them (although the magnitude in the change of developmental pace differs widely between taxa and environments). First there is seed germination, which is controlled hormonally. ...


10

Photosynthetic pigments are the chemicals which take part in photosynthesis, in particular they are they ones which absorb photons and fluoresce (emit photons of a different wavelength) or emit electrons. Pigments are molecules, and chlorophyll is a key example. These pigments are required for photosynthesis to take place, as they generate the electrons ...


10

Yes, plants of all sizes can have cancerous growths. Agrobacterium tumifaciens, the causative agent of crown gall disease, produces what is called a tumor. See this link for detailed information on these growths. Alternatively, use a plant physiology textbook to look up the above terms. (Here, is where a textbook is better than a single abstract in PubMed.) ...


10

Peach, apricot, plum, pear, apple, cherry trees are plants of the same family, Rosaceae, so they are closely related. They share many more aspects than the five petals. In fact, other plants in this family, and even many other dicots have five petal, simply because their share a common ancestry.



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