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25

The short answer is that as long as the vegetable/fruit is fresh looking - i.e. the cells have not disintegrated - they will be respiring, many cells will be functioning quite normally, and the plant is still technically alive. In cases where the part of the plant we treat as a vegetable is a part intended for reproduction (e.g. a seed, or a tuber like a ...


21

Cellular respiration in plants is slightly different than in other eukaryotes because the electron transport chain contains an additional enzyme called Alternative Oxidase (AOX). AOX takes some electrons out of the pathway prematurely - basically the energy is used to generate heat instead of ATP. The exact purpose of AOX in plants is still unclear. Plants ...


16

There are quite a few questions and thoughts in there, I'll try to cover them all: First, to correct your initial word equation: During photosynthesis, a plant translates CO2 and water into O2 and carbon compounds using energy from light (photons). You are correct to assume the C is further used for the growing process; it is used to make sugars which ...


13

There are several key ways in which rising atmospheric CO2 concentrations will affect photosynthesis, and these are related to the different types of photosynthesis. In order to properly answer your question, I'll provide some background about photosynthesis itself. Photosynthesis evolved in a high-CO2 atmosphere, before the oxygen-enrichment of the ...


13

There are some other good answers which provide part of the picture, but I think there is a fundamental organising principle which has been missed. Konrad has touched on it in his answer. The reason trees, and most plants, tend to grow equally in all directions is that they have iteratively generated branching and radial symmetry which is controlled in a ...


13

It looks to me (although I'd want to use a microscope to check) like the black dots are xylem. When you cut the fruit, you've severed the xylem and also exposed the flat surface. Three main things have then happened: The increased surface area has led to the 'fleshy' part of the fruit contracting as the cells dehydrate. The stiffer, lignified xylem tubes ...


13

There are 5 answers, all "yes". First: there exists at least one animal which can produce its own chlorophyll: A green sea slug appears to be part animal, part plant. It's the first critter discovered to produce the plant pigment chlorophyll. The sea slugs live in salt marshes in New England and Canada. In addition to burglarizing the genes needed ...


11

I wanted to add a little more to the excellent answer above, especially since the OP asks about research into this question in a "real-world context". There is a substantial body of evidence on exactly this question that comes from experiments at "Free Air CO2 Enrichment" (FACE) sites. FACE is an experimental method/technology in which standing ecosystems ...


10

Yes, plants of all sizes can have cancerous growths. Agrobacterium tumifaciens, the causative agent of crown gall disease, produces what is called a tumor. See this link for detailed information on these growths. Alternatively, use a plant physiology textbook to look up the above terms. (Here, is where a textbook is better than a single abstract in PubMed.) ...


9

Most water moves up through the xylem by capillary action. Imagine dipping a pipette into a small pool of water; the water would rush up into the pipette. Or, imagine dipping the edge of a paper towel in water. The water "runs" up the paper towel. This is capillary action. As water evaporates out of the leaves and such in higher regions of the plant, a ...


9

Plants will be respiring continuously, which is an exothermic process. Therefore the plants will be producing a small amount of heat. The protection from frost may be more a result of the vastly smaller convection current of the coat compared to the atmosphere rather than by reducing any conduction away of heat produced by the plant, however. Keeping the ...


9

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 ...


8

This is a question for which, I think at the moment, we don't have a clear answer. It is important to bear in mind that the leaf plays a number of important roles in the plant (photosynthesis, thermoregulation etc.) so leaf shapes probably evolved through a process of successive trade-offs. This may make it difficult to identify the exact selection ...


8

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, ...


8

Pumpkins, squashes in general, grow on vines, while apples grow on trees. Vines are fast growing and trees are not. Zucchini can be quite large; cucumbers, too. Pears, plums, peaches and other tree fruits do have a reduced variation in fruit size. While I do not know the answer to your question, my background in plant biology tells me that this is an ...


8

Growth in plants is tightly controlled by auxins – plant hormones. Auxin itself usually has an inhibitory effect on growth. As far as I know there is no active control to restore plant symmetry once it has gone awry (but I could be wrong!) but the inhibitory effect of auxin synthesised at the meristem and diffusing in all directions causes a symmetrical ...


8

Animals and plants are both classified as Eukaryotes, and as such can form large, complex, multi-cellular organisms. There are several major differences at the cellular level that distinguish the 2 Kingdoms (Animalia and Plantae). Without getting technical, the most crucial difference in relation to your question is that plants contain chlorophyll, and as ...


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

In general, plant cells only undergo differentiation at special regions in the plant known as meristems. Two of the primary types of meristem are the root apical meristem (at the tips of roots) and the shoot apical meristem (at shoot tips)^. Within the shoot apical meristem the plant cells divide and begin to differentiate into different cell types (such as ...


7

They don't always. For example, this apple tree grows just outside my window: So far, it hasn't fallen over yet. The reason it grows that way is because all the light is coming from the right side of the picture: the tree leans roughly to southeast, while the building is to southwest of it and casts a shadow on the center of the yard for much of the ...


7

If you mean the efficiency at which plants convert light energy to chemical energy (in sugar or other reduced C compounds) then there is definitely variability between plants, both at the species and individual level. The photosynthetic efficiency WP page gives ranges of between 0.1 and 8% of total solar radiation converted to "biomass", but these values are ...


6

Firstly, different genera of trees can occasionally be successfully grafted. For example, quince, genus Cydonia, may be used as a dwarfing rootstock for pear, genus Pyrus. However, it is true to say that this is the exception rather than the rule. In the case of plants in the family Cactaceae, I would suggest that grafting is usually successful for two ...


6

Actually, the units are °C days  or °F days. The units are mostly given in the typical name, Growing Degree Days where which temperature unit is meant is understood from the context. Much more important is knowing the base temperature ("T_base") since this value can be different in different usages, even for the same type of organism.


6

There are a couple of answers to this question. Especially where trees are concerned, you can graft two or more trees onto the same rootstock, or even a single limb into a tree. But if the graft takes, it won't behave too much more differently than just more branches of the same tree. Structurally intertwining them will not be different than if you had ...


6

During the daylight, the plant is photosynthesising faster than it is respiring so there is no net uptake of oxygen (the oxygen of course being produced in the as part of the photosynthesis). Of course, this only applies for tissues where photosynthesis is occurring. In the roots of the plant, oxygen must always be present in the surrounding soil/growth ...


6

This is basically the same that happens after pruning and involves a basic hormonal regulation mechanism in the plants. What happens is that the cut piece of the wood forms a new meristem which allows the growth of new organs. What’s important is that there is no other growth happening nearby, since that would hormonally inhibit any further growth. This is ...


6

The mechanism is called "capillary action". It requires a tube of a small diameter and happens because of the adhesion of water to the walls and the cohesion within the water (=surface tension).


6

First let me say this: I am no gardener. Every plant that enters my home or yard dies a slow death of neglect. I do have some experience trying to remove weeds from other non-weeds, and there is a practical aspect of "uproot every GMO plant" that I think may be impossible, but this is speculation. Let's get into a literature review. A frequently cited paper ...


6

Shigeta submitted his answer as I was writing this! Sanseveria is one of a wide group of plants (mainly succulents) that adopt a photosynthetic strategy referred to as crassulacean acid metabolism (CAM). Recall the basics of photosynthesis. The light-dependent reactions use energy from captured photons to generate ATP and NADPH, with the generation of O2. ...


6

The distribution of temperate hardwood forests, as well as deserts, tundras, savannahs, and other ecosystems, is determined primarily by average climate conditions, specifically average annual temperature and precipitation. You can see how biomes are related to climate in this figure, taken from Whittaker (1975): Temperate forests tend to be between ...



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