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15

Photosynthesis is nearly all visible light. There's usually not enough UV and thermodynamics more or less rules out infrared. Chris covered that pretty spectacularly, but that nearly is significant. There is some evidence that certain kinds of fungi can use gamma rays or other ionizing radiation for energy, but they're not particularly common. Melanin is ...


13

Photosynthesis only occurs in the visible light.have a look at the absorption spectra of the di fferent pigments involved in photosynthesis, you see that all these pigments absorb light between 400 and 700nm (from the here): You see that the absorption spectra of chlorophyll a and b are located from 400 to 500nm and again from 630 to 700nm. The maxima for ...


11

They are not individual cells. In fact, the "juice sacs" (as they are known) are actually specialized, multicellular hairs: Juice sacs originate as multicellular hairs in which the interior of the enlarged distal part breaks down and fills with liquid. The juice sacs constitute the fleshy, edible pulp of an orange and are the source of the sweet juice. ...


10

I have been looking into this for days, but this plant is difficult to identify without its flower. I reached out to a botanist at Dartmouth, who suggests that it is either one of two species-- a nasturtium (Tropaeoleum sp.) or a geranium (pelargonium). The leaves are what are called peltate, meaning shield-like with the stem attached directly underneath. ...


6

That is a beautiful Pink Quill, or Tillandsia cyanea. I have included two websites below about this plant, both of which include care tips. http://home-and-gardening.info/2009/09/18/a-guide-on-growing-tillandsia/ http://houseplants.about.com/od/bromeliads/a/Bromeliads.htm


5

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 rejuvenates them, and they grow as new trees. I'll take apple trees as an example. As you can see from the table here, there is a distinct age after which the tree ...


5

Viruses can infect just about any living thing, so that it could infect a plant is no surprise. Your article describes how a small virus-infected part of a plant had been cloned and consequently the entire cloned plant was infected, and it infected plants grown hydroponically in the same water. No surprise there either. Plant viruses have been known for ...


5

The scientific answers are pretty clear: Gingkos are not closely related to the conifers, they are closer related to the cycads. See this phylogenetic tree based on the 18S RNA from paper 2: It shows that conifers and Ginkgos are relative close related, but not on the same sub-branch of the tree. The last common ancestor between Ginkgos and Conifers is ...


5

Oxygen is good for animals because our basic metabolism is this: High energy carbon molecules + O2 → energy + H2O + CO2 Plants do that too at night, but during the day, they mostly do this: High energy photons + H2O + CO2 → High energy carbon molecules + O2 Rubisco, one of the most important enzymes in photosynthesis, can bind to O2, leading to ...


4

It means that the plant is a hybrid. Having it in the middle means that it is between species of the same genus, else the × (it's not the letter x but the multiplication symbol ×) would have been in front. It is very commonly used in taxonomic nomenclature, namely every time you have a hybrid. This means you'll usually see it with plants, as animals very ...


3

These are just a couple of short examples, but Witch's broom structures in trees can sometimes be caused by viruses - see Wikipedia: Witch's broom (fungi is maybe the most common cause though). In rose species you also have the similar Rose rosette disease (also called witches’-broom of rose), which is caused by a virus. The same webpage from Missouri ...


3

You are right, there are marine angiosperms that complete their whole life cycle underwater. Those plants are commonly called 'seagrasses', all occuring within the order of Alisimatales and distributed over 4 families, 12 genera and 58 species (Wikipedia). According to Les et al. (1997), a marine habit is highly correlated with certain reproductive traits, ...


3

Phosphinothricin is a metabolite from the bacteria Streptomyces viridochromogenes which has a protein called phosphinothricin N-acetyltransferase (PAT). This Protein inactivates the phosphinothricin which is the reason why S. viridochromogenes is not dying from it. If you want a plant to be resistant to phosphinothricin you can add the gen for the PAT ...


3

As the name implies, reflectance spectra are measured from light reflected off an object. Any object with reflects light, such as any opaque object) will work for this technique; to me this seems like solids are ideally suited for reflectance spectrphotometry. You might be used to transmission or absorbance spectrophotometry, which measures the amount of ...


3

Yes. The research team, led by the Durham Centre for Crop Improvement Technology, and including experts at the University of Nottingham, Rothamsted Research and the University of Warwick, have discovered that plants have the natural ability to regulate their growth independently of Gibberellin, particularly during times of environmental stress. They ...


2

As far as I know there are 5 receptors for far-red and red light which are the phytochroms(phyA-phyE) Its all about the ratio between red and far-red light. Each phytochrom has an active(PR) and an inactive(PFr) conformation. phyA is the only phytochrom which is activated by far-red light. (Only if the ratio between red and far-red light is low.) The other ...


2

The distinction between male and female is not that clear in plants, at least at the level of individuals. Actually the details may be rather complicated (see [1]), but in general we can distinguish between plants that have: male and female individuals (dioecy) male and female flowers on the same individual (monoecy) flowers that have both male and female ...


2

On the Botany department website of Purdue University (http://www.btny.purdue.edu/weedscience/moa/ACCase_Inhibitors/text.html) I found the following information on Acetyl-CoA carboxylase (ACCase) inhibitors: [...] (ACCase inhibitors) inhibit the enzyme carboxyltransferase, an [...] Acetyl-CoAesterase which speeds the formation of malonyl-CoA from ...


2

Male flowers have no ovary and do not produce a fruit but females need to be pollinated or the fruits will be aborted falling off when they are about golf ball size (1). Therefore, you will need at least one male or hermaphrodite plant with your female plants so you can manually pollinate the female plants. Also, note that hermaphrodites can pollinate ...


1

The already given answers are correct, but I think explaining basic metabolism does not answer the problem of how big organisms can grow. The argument about metazoan body size and the growing athmospheric O2 levels is that this latter process makes the diffusion of oxygen through animal tissue faster (because of the growing partial pressure of O2). This, in ...


1

Plants do not need CO2 for survival. They need it just for photosynthesis; if you supply them with alternate carbon source such as glucose then they would survive (See here for non-CO2 Carbon-source utilization). There are non-photosynthetic plants which are totally dependent on carbon sources other than CO2; some are carnivorous like venus fly-trap. I am ...


1

For grafting to "take", the the two plants' vasculatures have to be organized similarly. This is not possible for two such differently organized stems as a pepper and an apple. This is a cross section of a young woody stem (such as an apple, though this example is a tilia): This is a cross section of an herbaceous stem (such as a pepper): You can see ...


1

One can sometimes notice street lights delaying the annual shedding of leaves in some species (a well-lit branch will be mostly green while the rest of the tree is turning). So at least part of it would be day/night length in at least some species. I would expect, however, that the answer varies based on species, genus, and/or family, and that there are ...


1

The largest area of temperate rain forest in the world is on the west coast of North America, which has a summer dry season. In other words, at precisely what would be the best time for plants to grow (based on temperature), there's a shortage of water. (Summer vacation visitors to the rain forests on the Olympic Peninsula are often wondering "where's the ...


1

Polygonum cuspidatum, common name Japanese knotweed. A notorious invasive species. It's actually a herbaceous perennial (those stems grew in just one season, and will die back to the ground at the first hard freeze), not a shrub. The red things are ripening seeds, not flowers.



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