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10

Peach, apricot, plum, pear, apple, cherry trees are plants of the same family, Rosaceae, so they are closely related. They share many more aspects than the five petals. In fact, other plants in this family, and even many other dicots have five petal, simply because their share a common ancestry.


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

Basically just search "thing you want" and "phylogeny" and you'll find a million results on Google. For you, I might recommend the Botanist in the Kitchen blog, which has a whole page on the subject and has assembled this phylogeny, including many, many others. It's pretty impressive!


7

Disclaimer: This is not my field of research. First, this is not a complete answer to our question. A nice explanation of the current hypothesis of water transport in trees (Dixon-Joly cohesion-tension theory, originally proposed 1894) can be found at The Amazing Physics of Water in Trees but also in Tyree (1997). The key points are that the stoma (leaf ...


6

If you mean if there are viruses, pathogenic bacteria or fungi that may cause diseases both in plants and in animals, the response would be that this is very unlikely (But even so, some fungi and bacteria could do it if some circumstances are given). This is due to some key factors: First of all, the philogenetic distance between plants and animals is huge. ...


6

It is a Mimosa pudica, a wonderful plant. According to wikipedia you can find it in the following places: Mimosa pudica is native to South America and Central America. It has been introduced to many other regions and is regarded as an invasive species in Tanzania, South Asia and South East Asia and many Pacific Islands. It is regarded as invasive in ...


5

Quantitative descriptions of leaf shape used as diagnostics are hard to come by. There are numerous qualitative descriptions (lyrate, cordate, acicular, etc.), and I think this fits within the example you give that "the laminar shape for this species is mainly ovate." But actual quantitative ranges as you mention (e.g., that the L:W ratio of Acer lies within ...


5

Perhaps the question may also be phrased, "Why is it common for plants to produce chemicals that possess pharmacological or toxicological effects in man and animals?", and to that question it is often reasoned that plants, being sessile and otherwise defenceless food sources for predators, produce compounds that affect the physiology of animals in such a way ...


5

There are many different kinds of plants that have independently evolved this sort of variegation (non-green areas) in the leaves. However, the mechanisms by which they effect this vary between species. Some have little or no chlorophyll in the non-green areas, but many others have changed the architecture of their leaf cell layers in the non-green areas, ...


5

The three main cues for flower opening/closing used by plants are temperature, light and humidity (van Doorn & van Meteren 2003, freely available pdf), with the first two being most common. Plants with daily opening and closing of flowers can be divided into nocturnal (open at night) and diurnal (open at day). There exists several different mechanisms ...


5

cis-3-hexenal is probably the main reason. It is one of the main chemicals in fresh-cut grass smell (lots of references besides wiki if you google it). This fairly comprehensive paper on watermelon odorants also says that they find a lot of cis-3-hexenal in fresh cut watermelon. See tables 3.1, 3.2 and 3.3.


5

While it's true that cellulose is full of calories, it's very difficult to get the calories out. Symbiotic bacteria take ages to digest cellulose, and as a result animals that digest cellulose with specialized symbiotic bacteria have a huge gut to house them in. It's likely that the reason humans can't digest cellulose is because mammals generally can't. ...


5

The cost would increase; either because pollination services are not provided and the supply is decreased; or because the cost to producers goes up as they must pay for artificial pollination. See the extremely detailed analysis in Winfree et al. edit I imagine what you're actually asking for is a $ figure "per apple". This depends on the location, crop, ...


4

Your question conflates two separable events, a redox process and an acid-base dissociation. The interconversion between disulfides and free sulfhydryls is a redox reaction, governed by the redox potential of the surroundings. The importance of redox potential to the -S-S- <> -SH equilibrium is illustrated by the difference between the cytosol and the ...


4

According to Paul Stamets, Gomphidius glutinosus is especially well suited to collecting Cesium-137: G. glutinosus has been reported to absorb – via the mycelium – and concentrate radioactive Cesium 137 more than 10,000-fold over ambient background levels. That article and Stamets' book Mycelium Running have more details on other species.


4

Firstly, most plants or other natural medicinals existed way before we knew about them; it's not that plants mimic drugs, its that drugs mimic plants. To answer your question succinctly, compounds that we can use for our own medical benefit often do other things, we just adapt them for our own purposes. Penicillin is probably the best example. It didn't ...


4

Why don't we have any enzyme to digest cellulose? Why should we? We don't use it as a source of energy so why bother? Even animals that do "digest" cellulose, like ruminants, only do so because of symbiotic bacteria; it would be a poor system indeed in which every organism utilized the same resource. We occupy enough of the food chain as it is.


4

This is a "Tar Spot" disease usually found in Europe and North America. It mostly affects the Maple tree leaves. Tar spot is caused by 'Rhytisma acerinum' a plant pathogen fungus. This pathogen does not seem harm to tree but disturbs the leaves as it finds a suitable condition in summer with bit of wetness. It enters the leaves through stoma and then creates ...


4

According to this news article, in a NASA experiment one man survived for 15 days in a sealed chamber containing 30,000 small wheat plants. If you read the article you will find that this did not produce a completely balanced system - some excess oxygen had to be removed, and some extra CO2 had to be pumped in.


4

I remember overhearing a botanist some 10 years ago, that he cannot tell male poplar from female when they are not flowering or producing seeds. Poplars and willows are related, so it is a weak indication for you, you will likely not find any visible features in willow neither. But it is an old information, too. (Are you interested in DNA sequencing ...


3

Chlorophyll is organic, not living, which is a fancy way of saying that it contains carbon. As for your question about boiling, it depends on whether or not the heat from boiling will disrupt the chemical bonds and destroy the molecule. According to Wikipedia, chlorophyll a will melt at around 117°C (I'll assume that chlorophyll b is similar), which is ...


3

Some functions of non-green flower colors: #1: plant-animal interaction. Flower colors act as signals received by animals with eyes (e.g., pollinators, which many plants need to attract in order to reproduce). However, it sounds from your question as if you're looking for other physiological effects. Two that come to mind are: #2: heat. Flower color and ...


3

Members of the Cucurbitaceae family (squash, pumpkin, cucumber, melon etc.) are unique* in that they possess two distinct phloems, see figure below. The fascicular phloem (FP) is the main transport conduit, and more closely resembles the phloems of other plant families. Its role is to transport photosynthates and other nutrients (Turgeon & Oparka, ...


3

First, allow me to provide the link to an old paper that deals with development in Ananas comosus, it should be freely available and answer this question in more detail: http://onlinelibrary.wiley.com/doi/10.1111/j.1469-8137.1936.tb06884.x/pdf Now, to briefly explain the observation that a mature plant will grow from the region where the leaves of the ...


3

As far as I know, the main challenges the plants have to face in cold environment are metabolism reduction and membrane fluidity. If the temperature is even lower, they may face freezing. Increasing the metabolism is quite hard, because plants usually are unable to increase their temperature by its own. Plant may produce more pigments in order to absorb ...


3

There are no roses (that is, flowers of genus Rosa species) that naturally express a "true" blue color. Through cross-breeding, there are lilac-mauve rose horticultural varieties ("Blue Nile","Blue Moon","Lady X", etc.), and through genetic engineering (actually inserting delphinidin-producing genes) there are mauve-lavender varieties ("Applause"). The ...


3

I'd argue that this relates to species-specific strategies of seed dispersal, so the answer depends on which species you're asking about. Here's an answer for chili peppers, which I think illustrates how complex and idiosyncratic these strategies can be. As I mentioned in this answer, the seedsavers' manual Seed to Seed has great info on most plants, ...


3

Papain is a cysteine protease, for which Wikipedia should be sufficient: Cysteine proteases play multi-faceted roles, virtually in every aspect of physiology and development in plants such as in growth and development, in senescence and apoptosis (programmed cell death), in accumulation and mobilization of storage proteins such as in seeds. In addition, ...


3

I don't think it's wise to use a spectrophotometer for this experiment, as it is a total count, i.e. it can't distinguish between dead and alive cells very well, and so she might not see a clear difference between her treated and untreated algae. If she has access to a haemocytometer and a good microscope, then she can count the living cells directly, and ...


3

The chloroplast, having multiple circular copies of its chromosome and its own tRNA and ribosome genes more resembles the bacterial systems it is descended from. See @A.Kennard comment Polysomes being found in bacteria frequently are single mRNA to which are attached multiple ribosomes. This paper shows that chloroplast polysomes were observed in the mid ...



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