45
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If plants benefit from carbon dioxide, why is car traffic something bad?
There are at least two separate answers to your question. First, with respect to plants needing CO2, they have evolved to deal with the limited amounts of CO2 normally in the atmosphere. That's ...
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44
votes
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What is it that creates that wonderful smell after a fresh rain?
That molecule is called Geosmin. It is mainly produced 1 by Actinomycetes such as Streptomyces which are filamentous bacteria that live in soil. Other organisms also produce geosmin:
Cyanobacteria
...
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40
votes
Why do some vegetables taste bitter?
Nice question! Many vegetables taste bitter because they contain compounds known as phytonutrients (Greek phyto = "plant"). There are more than 2500 phytonutrients known, and the most important (and ...
37
votes
If plants benefit from carbon dioxide, why is car traffic something bad?
Exhaust gasses from combustion contain many compounds in addition to CO2.
Some of them under the right circumstances‡ can be of limited benefit to some plants, but others such as ozone are damaging ...
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20
votes
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Is this a grass cell?
It's not a single grass cell, but this does indeed appear to be a micrograph of a leaf of grass—so it actually contains numerous cells. Here's another image I was able to find with a much more ...
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18
votes
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If plants "alternate generations" between sporophytes and gametophytes, why don't we say the same of humans?
The big difference is that in humans, there is no mitosis in the haploid phase.
There are three terms that are important here:
Haplontic: Most of the life is spent in the haploid phase
Diplontic: ...
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18
votes
Is it scientifically sound to pool repeated measurements?
If you use the configuration on the left, your variance across tubes reflects variance between individuals.
If you use the configuration on the right, your variance across tubes reflects primarily ...
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16
votes
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Why do some vegetables taste bitter?
Bitter taste is sensed by bitter sensitive gustducin receptors (T2R family). There are different types of bitter receptors and they can be triggered by different kinds of ligands. Different classses ...
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15
votes
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How can Valonia ventricosa cells get so big?
Ventricaria ventricosa (previously called Valonia ventricosa) is not exactly a single cell. It has a coenocytic structure with multiple nuclei and chloroplasts. As Jasand Pruski correctly guessed the ...
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15
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If plants benefit from carbon dioxide, why is car traffic something bad?
Firstly, I don't think it's entirely clear whether the entire premise of the question is correct. I couldn't find any evidence to suggest that plants don't thrive on highways and areas with lots of ...
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14
votes
Is this a grass cell?
This is a transverse section (T.S.) of leaf blade a sort of Xerophytic (Desert-climate) grasses. such as Ammophila arenaria , Spartina sp, Agropyron sp, Poa pratensis etc. However similar-type-...
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14
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Why do birches have a white bark?
It is protection against rapid warming of the cambium layer. A lot of far northern timber has light colored bark which reflects sunlight. The rapid heating from very cold after sunrise can actually ...
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14
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Can plants produce oxygen at night (without light)?
Short Answer: Any plant can produce oxygen at night, but plants cannot produce oxygen without light.
Longer Answer: It all comes down to spontaneity of a reaction i.e. whether a reaction can occur ...
13
votes
What determines the spiral direction of plants?
First of all, you assumption seems to be incorrect. Plants in same part of the world can twine in opposite directions.
Little seems to be known exactly. Gravity has nothing to do with plant's ...
13
votes
Why do plants store energy as carbohydrates and not as fats?
The question was:
Why would plants store their energy as carbohydrates and not as fats, if fats are a more efficient energy store?
But before trying to answer it you have to be quite clear what is ...
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13
votes
Are two colors (red + blue) necessary for LED grow lights, or would either color be sufficient?
tl;dr: Sort of?
Logically, either red or blue light should be sufficient. Chlorophyll a and chlorophyll b preferentially activate different photosystems, and both photosystems are required in green ...
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13
votes
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Why aren't leaves black?
Evolutionary answer: I like to go one step before green plants and consider the humble alga. Algae were historically classified as green, red, and brown, based on the wavelengths that their ...
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12
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If plants benefit from carbon dioxide, why is car traffic something bad?
Back in the early days of climate science, there were some scientists who considered the possibility that increased CO2 production would lead to increased plant growth, and that this in turn would ...
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11
votes
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What is the biological age of grafted plants?
In my experience (in common with the experience of everyone I've talked to who could be considered an expert on the subject), taking old wood and using that as a scion when grafting new trees ...
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11
votes
What determines the spiral direction of plants?
Having had a self-sown pumpkin grow in my back yard I can tell you what happened with the tendril in your picture.
The tendril started growing straight, with a couple of branches. When one of the ...
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11
votes
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How does coconut water solidify into hardened coconut meat?
There are three types of endosperms encountered in botany - nuclear, heliobial and cellular. The endosperm of Cocos nucifera is both special and interesting.
Initially, the cocunut is a nuclear ...
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11
votes
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What could cause spiral tree growth?
The two commonly put-forward explanations for spiral growth of tree trunks related to stress-loading and damage-tolerance.
The stress-loading explanation states that spiral-grained trees flex more ...
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11
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What part, roughly, of the carbon in a plant comes from the soil? As opposed to the atmosphere?
Only a small fraction of plant carbon is soil-derived: e.g. from Majlesi et al 2019:
although the majority of plant C was obtained from atmosphere by photosynthesis, a significant portion (up to 3–5%)...
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10
votes
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Why is it harder to sequence plant genomes than animal genomes?
The authors of this 2012 review article summarize the problem well in their introduction:
In contrast to the tremendous advances in throughput, assembling sequencing reads remains a substantial ...
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10
votes
What determines the spiral direction of plants?
tendril coiling occurs via asymmetric contraction of an internal fiber ribbon of specialized cells. Under tension, both extracted fiber ribbons and old tendrils exhibit twistless overwinding rather ...
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9
votes
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The colour of aquatic plants found deep under oceans
You're right that certain wavelengths of light are more capable of penetrating deeper depths of water. However, it turns out, blue light typically travels to deeper depths than all other visible ...
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8
votes
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Viruses selected by evolution
Welcome to Biology.SE!
About your title
Let me first react to your title: Viruses selected by evolution.
Evolution is any process of genetic (and eventually ...
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8
votes
Why are C4 plants mainly tropical plants?
This is not my field, so the following is based solely on a brief reading of Internet sources.
The Wikipedia entry on C4 carbon fixation states:
When grown in the same environment, at 30°C, C3 ...
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8
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If plants benefit from carbon dioxide, why is car traffic something bad?
Ignoring for a moment the other pollutants emitted from car exhaust, increased CO2 levels are warming the planet, through what is called the "greenhouse effect".
Photosynthesis is a set of reactions ...
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Only top scored, non community-wiki answers of a minimum length are eligible