Hot answers tagged botany
Angiosperms -- that is, flowering plants -- only evolved relatively recently on an evolutionary timescale, about 125 millions years ago. So for most of the history of life on earth there have been no flowering plants. Thus it seems highly likely that if angiosperms were to suddenly disappear, life on earth would continue. There might be a massive disruption ...
It looks very very suggestive for Artocarpus altilis or Breadfruit tree. Another variants - Artocarpus camansi.
It looks like the common Geranium sylvaticum (also called wood cranesbill or Mayflower), and it is at least a close relative (member of the Geranium genus). This plant is commonly found across Europe and in parts of Asia (see map below), and it is sometimes planted in gardens. It is a perennial herb that grows in many types of habitats (woods, meadows, road ...
The stinging hairs (trichomes) of the common North American nettle (Urtica dioica) are sharp, pointed cells. These nucleated cells are embedded in a base of smaller epidermal cells. The shaft of the trichome is composed of silica. Upon touch, the tip breaks off, leaving a sharp tip similar to a hypodermic needle. The hollow trichome penetrates the skin, and ...
My guess would be the meadow cranesbill (Geranium pratense), see this image (from here, more images are available there): The flower is quite common on meadows in europe, see here.
If the labelling is correct, this should be Camellia sinensis, the plant that produces black tea, green tea, etc. (although not many things that are commonly referred to or marketed as herbal teas). Thea is the original genus name given by Linnaeus to the species we now call Camellia sinensis. There's an old pharmacy tradition of specialized latin ...
Judging by this image in wikipedia, I would say Theae folium is another name (probably a name in another language) for Camellia sinensis
Firstly, it is not necessary that all dicots have stomata on their lower surface of their leaves. The lotus Nelumbo nucifera has its stomata on its upper surface, due to the lower surface of its leaves being in contact with water, and therefore unable to transpire effectively. The reason that stomata are usually on the lower surface has been analysed in ...
It depends on the plant. All angiosperms (as far as I know) will produce flowers even in the absence of pollinators, the question is whether or not the plant will bear fruit. Some species are wind-pollinated and do not require insects for pollination at all. They will bear fruit just fine without insect intervention Other species are self-compatible and ...
Germination of the pollen tube begins when the pollen grain becomes hydrated on the tip of the stigma. The pollen grain absorbs water and also exchanges signals with the stigma. Microchannels form between the pollen grain and the tip of the stigma papillae and water is transferred from the stigma to the pollen grain (Taylor 1997). cAMP, which is produced by ...
No, it would not be accurate to label them clones, and the organism still goes through sexual reproduction even if they are selfed. Selfed offspring would get two copies of the "same" chromosome (when selfed within the same prothallus), when the parent might have two chromosomes of different origins, and there will also be recombination during meiosis ...
In ferns (and seed plants) the dominant, largest stage of life is the diploid sporophyte. Within the sporophyte, meiosis occurs producing haploid spores. These spores are dispersed and grow into the small haploid gametophyte, AKA the prothallium. The gametophyte produces haploid gametes - both egg and sperm coming from the same individual, usually. The sperm ...
You can try http://timetree.org/ to get the divergence time if you already have the names of the taxa.
Maybe you could get some information from the Angiosperm Phylogeny Group: http://www.mobot.org/MOBOT/research/APweb/ They even have a tree where model organisms are highlighted: http://www.mobot.org/MOBOT/research/APweb/trees/modeltreemap.html
If you know the species name, you can search TreeBase to find previously published phylogenetic trees which will point you towards close relatives to your species. Depending on how obscure your taxon is, though, you might not find much.
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