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22

Ripening of bananas is induced by ethylene (see reference 1), which acts as a hormone and induces the ripening process. The incomplete combustion of the leaves produces ethylene, additionally the warmth of the process will help the enzymes as well. There is even a paper about this technique (although it is unfortunately not accessible), see reference 2 for ...


20

There was a 2011 study where they used a sensitive atomic magnetometer to try to detect a plant's magnetic field. They stated that: To our knowledge, no one has yet detected the magnetic field from a plant. Biochemical processes, in the form of ionic flows and time varying ionic distributions, generate electrical currents and time-varying electric ...


16

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 ...


14

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 ...


14

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

Most varieties of corn bred for modern use have between 8-20 rows of kernels (Bommert et al. 2013.. Nearly all varieties have an even number of kernel rows. This is due to the early development of the ear. Ears of corn are developed from pistillate flowers on the ear (Bortiri and Hake 2007). Pistillate flowers are the female flowers, so they will bear ...


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. ...


9

Basically, they don't. Ecosystems are pretty much either de facto, delimited by geographical boundaries, or defined by us. For example, an underground lake would be an ecosystem and it is organized in such a way for the simple reason that there is no communication between it and any other system. Most ecosystems however, do communicate. For example, we ...


8

They are basically conjoined apples which share a common stalk. They are rare but do happen. Here is an article of one discovered in a backyard. conjoined apple discovered in a store (reference) It apparently happens because of bad weather conditions, stress and insect damage. Fused fruits are also found in the case of cherries, watermelons, peaches ...


7

Trees need: Deep roots to get more water and anchor their growth. Strong trunks to support themselves against gravity. A vascular system to move water and nutrients throughout the tree. Small leaves that can be supported high by the trunk to compete for sunlight. Water plants need: Just enough root to anchor its location. No vascular system. Water is ...


7

In general for plants, before you start trying to make your own phylogeny, you should try to find an existing phylogeny. Phylogenetics is complex, and a lot of people have already done the hard work. You can start by looking at the Angiosperm Phylogeny to figure out which species are most closely related. To make use of the tree you will usually have to look ...


7

It's Echinacea. I've linked to one site but if you run an images search with Echinacea as the search term you'll see lots of examples. And here is the WP page. Supplementary Echinacea are members of the Compositae. The flower (the head) in your picture is actually made up of lots of individual smaller flowers (i.e. it is a composite flower). The petals ...


7

There is no color code for the leafs - the color results from biochemical reactions. Basically there are three colors: Green, yellow and red. Green color is caused by the chlorophyll inside the chloroplasts, when the leafs are active in photosynthesis. Yellow color is caused by Carotenoids, which are present in the leafs all the time, but are masked by the ...


7

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 ...


6

From How Do Pine Cones Open (Nature): The scales of seed-bearing pine cones move in response to changes in relative humidity. The scales gape open when it is dry, releasing the cone's seeds. When it is damp, the scales close up. The cells in a mature cone are dead, so the mechanism is passive: the structure of the scale and the walls of the cells ...


6

This looks pretty much like Buddleja davidii to me. They are available in a range of different colors, see this image from the Wikipedia:


6

Yes they can, but their normal growth is somewhat impaired. A study by Bugbee and collaborators showed that while the yield of rice and wheat increases with CO2 up to about 0.1% CO2, yield decreases sharply as CO2 climbs from 0.1% to 0.25%. There is a smaller loss in yield as CO2 is further increased from 0.25% to 2%. One interesting thing to note about the ...


5

There is absolutely no way to tell to be honest because mulberry trees have the capability of changing sex (reference). From a paper titled "Diversification of mulberry (Morus indica var. S36), a vegetatively propagated tree species", I quote The sex expression of plants appears to be a function of hormonal control; there seems to be evidence that ...


5

Well, that depends on your home. ;) I think it is not an easy process. There are two main methods that are used to genetically modify plants: Using the bacterium, Agrobacterium tumifaciens, as a vector for the DNA. Agrobacterium has the ability to infect plants and insert DNA into a plant's genome. It causes crown gall tumours in natural infections. This ...


5

Dried grains are very mostly viable means they are in a dormant state until and unless suitable condition are provided. More dried it will be viable for longer. In fact there are seed found in Siberia which are ~32,000 years ans still viable. Courtesy: National Geographic Source: US Emergency Supply: Introduction to Seed Viability


5

Howe and Smallwood (1982) provide a nice review of the many methods of seed dispersal that have evolved in plants. The review is broad but they do have a section on frugivory. They highlight hypotheses developed by McKey, and Howe and Estabrook (see Howe and Smallwood for citations) that suggest plants may use one of two strategies. One strategy is the ...


5

No, its not xylem. Bamboo is a grass, and the stem (culm) of many grasses are hollow in the middle (see e.g. Grass Structures from Oregon state for some more info). The exact reason for why Bamboo have hollow stems is most likely due to evolutionary contingencies. However, from a mechanical stability point of view, a hollow stem is much more rigid and ...


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

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

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

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

The article you have linked to does explain everything thoroughly, though in a somewhat complex way. I did not know how much genetics you actually know, so I tried to answer very thoroughly. So the article states that the gene Mendel studied and that was responsible for the white color of the pea flower is ANTHOCYANIN1 (in the article it is also called - ...


4

It reminds me of the smooth-barked Australian gum trees / eucalyptus, like a salmon gum, ghost gum, etc. Although there are no squirrels in Australia :) This photo of a Salmon Gum is from http://www.fpc.wa.gov.au/content_migration/plantations/species/arid/salmon_gum.aspx


4

Yes, D. Attenborough probably refers to ploidy number Ploidy number Humans for example are 2N (except during the spermatozoid and ovule phase of human existence) meaning that they carry two copies of each autosome (=non-sexual chromosomes). Some species are 1N (haploid), some are 3N (triploid), etc… It would actually be more correct to talk about the time ...



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