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Having separate male and female cones reduces self-fertilization just by the physical separation (the greater distance for pollen to travel gives pollen from a different tree a larger chance of successful fertilization). A much larger effect is from the timing of flowering, since on an individual tree the female cones will be receptive at a time when the ...


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I don't understand your hypothesis. But the number of pairwise differences between two cells assuming neutrality ($\pi$) in the two different branches in $\pi = 2 \mu L t$, where $\mu$ is the somatic nucleotide mutation rate (around $10^{-11}$ on average), $L$ is the length of the sequence of interest (eventually the whole genome). $L$ can therefore be of ...


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Sodium Chloride (which I am here assuming to be the major salt in your solution) has a solubility of 6 Moles/L this corresponds to 12000 mOsmol, so the 2000 mOsmol you are measuring is not entirely implausible. However normally plant cells should have an osmolarity on the order of 300-400 mOsmol. In order to judge if your value was calculated correctly, it ...


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Tap water does contain a significant amount of metal ions in solution, and this applies to all water sources (rainwater, groundwater) with the exception of ultrapure (eg distilled or reverse osmosis water). For example, the official analysis of the NYC water supply in 2015 shows that there are significant quantities of nitrogen, phosphorus and potassium in ...


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Any soil microbiology textbook will tell you that there are a great number of fungi in most soils. I believe there are 12 or 13 species of non-legumes capable of fixing atmospheric nitrogen. Podocarpus is one of them. Look at the roots of podocarpus and you will see nodules all along the roots.


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If you did enough replications in your experiment, you could harvest one or more plants and measure fresh weight, and then gently oven dry for about 48 hours at like 160 degrees F and then take a dry weight as a measure of biomass. I don't know a non-destructive way to do it. A lesser alternative would be to measure plant height and number of leaves, though ...


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I like the reference book Plant Physiological Ecology for stuff like this. I know one of the authors is Thijs Pons. When temperatures become high, plants may close the stomates to conserve moisture. When the stomates are open, usually in daylight hours, the open stomates allow CO2 to enter the leaf. This carbon is needed to form glucose and many other ...


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Can I calculate the estimate through a simple measurement (e.g. of plant weight) or does it require tight lab experiments? In the former case, how is that measurement made? In the textbook Plant Physiological Ecology*, they state that about 40% of the dry weight of plants is carbon, and I believe the vast majority of that is from CO2 from the ...


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You may find it an interesting sidelight that in many plants with potassium deficiency, we see necrotic leaf spots or leaf tip or marginal burn. The plant can't adequately close the stomates, so you get localized dessication in the leaf and therefore necrotic leaf spots. In this way, drought stress and potassium deficiency are somewhat related.


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Mature, viable seeds have to form in most fruits, which involves the maturation of embryonic tissue. That can take a little time, from just a few days in some weed species to months and perhaps longer in some fruits like pineapple.


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There is a bougainvillea variety called 'Surprise', which puts out bracts either white or magenta in color, though I believe all of the actual flowers are white.


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In addition to the above answer : Carbon dioxide : Increase in CO2 level in the atmosphere over 0.03 % causes stomatal closure and results in decrease of transpiration.


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Flaccidity in plant cells The failure to display turgidity especially as seen with plant cells. The suspension of cells from plants in isotonic solutions results in the state termed flaccidity. On a cellular level it represents a lack of pressure of the plasma membrane against the plant cell wall. A more extreme state, termed plasmolysis, is seen ...


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We can consider two processes that a seed might care about: (1) Ordinary chemical reactions that just happen in the cytoplasm of the seed cells. It's very hard to stop chemistry! Even in the freezer, chemical reactions occur (slowly). This is why long-term storage of biological specimens is generally in an ultra-cold freezer (-80C). Chemical reactions could ...



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