Study of the normal functioning of plants and plant cells

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Can plants live forever? [duplicate]

I know that some plants die for old age like a lettuce. But there are trees like Baobabs or larger Ficus in the tropics of whom we don't know their age. And trees like spruce reaching 9950 years old, ...
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54 views

How did the introduction of artificial light changed the life cycle of a plant?

Plants in urbanized areas are constantly exposed to artificial light after sunset. In their natural habitat there is a more distinct day and night cycle. Since light is an important factor in a plant ...
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2k views

Why do organisms excrete nitrogenous wastes?

All plants and animals excrete nitrogenous wastes in the form of urea, uric acid or ammonia. But isn't that a bit of a waste? I mean, there is a shortage of biologically available oxygen in the ...
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256 views

How do plants intake minerals through their leaves?

How do plants intake the fertilizer when it is sprayed all over the leaf surface as a foliar feed?
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103 views

Gender and age-specific mutation rate in plants

Background General concept According to Cochran and Harpending (2013), mothers transmits on average a number $x$ of new mutations to their offspring. This number $x$ is independent of the age of the ...
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45 views

Is there a model perennial plant species?

Most of plant science is conducted on small annual species with short life cycles; predominantly Arabidopsis thaliana, but also a handful of others like Oryza sativa and Medicago truncatula etc. Is ...
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1k views

Regulation in plants bearing cleistogamous and chasmogamous flowers

In most plants bearing cleistogamous flowers, chasmogamous flowers are also borne by the plants. For example, Viola, Oxalis and Commelina contain both these kinds of flowers.( I am unaware of a ...
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What is the effect of a pure-oxygen environment on a plant?

Just read What's the effect of oxygen deficit on plants? ; and wondered whether the opposite would have any effect on a plant. That is to say, if a potted plant were placed under a bell-jar and ...
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340 views

What determines the autumn leaf color?

It is autumn out there. Green, brown, red, yellow, and mixed-colored leaves drop from the trees to the ground. What determines the colors of the leaves? Wikipedia tells me Leaf senescence is the ...
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92 views

What could cause spiral tree growth?

While hiking through one of the areas burned in the 1988 Yellowstone fires, I noticed that some of the trees appeared to have grown in spiral patterns. Most downed trees have crack patterns that ...
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684 views

Photosynthesis: What Powers the Splitting of Water?

The splitting of water is an endergonic (non-spontaneous) reaction, and thus would require energy (chemical work to be done) in order to happen. In Photosystem II, an enzyme catalyzes this splitting, ...
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515 views

Do all plants photosynthesize with equal efficiency?

Just what the title states. Given identical, necessary and favourable conditions (Probably nutrients, humidity, and light but what I mean is all necessary requirements are fulfilled) - Is ...
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730 views

What types of light can't a plant photosynthesize in?

I have a plant on my desk, and it got me to wondering: Can my plant use the light from my monitors to photosynthesize? If so, what light (apart from green light, to a degree) can't plants use to ...
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143 views

Can you tell the sex of a white willow when it's not flowering?

Can you tell whether a salix alba tree will produce male flowers or female flowers by looking at it, touching it or generally using your unaided senses? If not, is there any way to do that without ...
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1answer
244 views

Why dont “growing degree days” have units of degrees Celsius (or do they)?

From Wikipedia: Growing degree days (GDD), also called growing degree units (GDUs), are a heuristic tool in phenology. GDD are a measure of heat accumulation used by horticulturists, gardeners, ...
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How would a plant sprout and grow in a zero gravity environment?

Have any experiments been carried out involving sprouting and growing plants in a zero gravity environment? If so, what was the outcome? How did the plants sprout out of the soil without gravity? Did ...
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1answer
77 views

How does CO₂ concentration affect photosynthesis?

I have heard the theory that with the increase of CO2 in the air, the speed of the photosynthesis would increase, thereby limiting the increase of CO2 levels. What is currently the rate limiting ...
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98 views

Photosynthesis regulation

I read about the regulation of Calvin cycle by thioredoxin which activates key enzymes essentially by converting disulphide linkages on inactive enzymes into sulfhydryls. Another regulatory mechanism ...
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1answer
53 views

Total dark deprivation at day-neutral plants

First of all, I am not a biologist. Almost for a week, a question has come to my mind: "Is it harmful ceaselessly exposing a plant to light?" (I mean with natural & artificial light with ...
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1answer
379 views

Measuring algae growth or death

My daughter (10th grade) is doing a science fair project on the toxicity of triclosan for the algae Selenastrum capricornutum. She is wondering the best way to measure the effect, given the limited ...
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214 views

How many ATP are formed?

What is the number of ATP molecules formed during the photosynthetic processes which consume 8 molecules of $\text{H}_2\text{O}$ due to noncyclic electron transport and subsequent ...
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67 views

Why do we need to put phosphate fertilizers along with rhizobium?

Isn't phosphorous a macro nutrient? So it should be present in the soil in sufficient quantities... but still we add phosphate. Why?
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601 views

Why does wood become darker when it ages?

I have lots of pieces of pine furniture which have different colours depending on how old they are. So, I just wondered why that is. I guess it has something to do with structures and chemical ...
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1answer
75 views

Why are some plants frost tender?

Why do some plants have the ability to stand frost, while others can't? Does it have to do with the size of the water vacuoles in the plant cells?
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How does a garlic clove thrive inside a closed refrigerator?

A garlic clove has been growing very well inside a closed refrigerator. It has developed beautiful green stalks, which I think are the equivalent of leafs. Since they are green, I assume they ...
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303 views

How is photosynthesis observed?

How is photosynthesis observed? Say I have plants A and B, and I want to find how fast they are able to turn carbon dioxide into oxygen. How would I experiment this? Say I have one plant A, which ...
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133 views

Is chloroplasts per cell indicative of the photosynthetic power of a plant?

Plant-A has on average N chloroplasts per cell. Plant-B has on average M chloroplasts per cell. If N > M, is plant-A more efficient in turning carbon dioxide into oxygen? Also, is it possible to see ...
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1answer
474 views

Sporophyte and gametophyte

My textbook says that in both groups of seedless plants (vascular plants, non-vascular plants) the gametophyte is a free-living plant, independent of the sporophyte. I don't understand this statement ...
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Online course on Plant Taxonomy and Physiology

After following a course in Permaculture, I realised that if I want to get serious about it, I need to be able to distinguish plants. So I am looking for an online Video course on Plant Taxonomy and ...
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1answer
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Why did the sensitive plant (Mimosa pudica) evolve its leaf-closing mechanism?

Why did the sensitive plant, Mimosa pudica, evolve its leaf closing mechanism? Does it help in a heavy storm? Does it scare off whatever animals might think it a good meal?
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1answer
35 views

Determine which seed will germinate first

I recently studied about plant physiology for a test. Strangely, there was this question which I had no idea how to approach. The question is, Which seed will germinate first? a) Castor b) Wheat ...
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1answer
27 views

Accuracy of best plant growth models?

Given a plant $P$, predict its height $H$ at time $t$ since planting given some environmental variables $E_1, \dots, E_n$. How accurate are the state-of-the-art models for such thing? What data is ...
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2answers
149 views

Can carnivores survive on a (processed) vegetarian diet? Why or why not?

There are many differences in for example the digestive system between carnivores, herbivores and omnivores. It seems that in certain kinds of species adaptability with respect to diet is possible. ...
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1answer
1k views

Which are mobile and immobile elements in plants?

I am confused with this element or nutrient classification in the plants, since some authors set elements like $\ce{S}$ and $\ce{Ni}$ as mobile and other as immobile elements (Citation 1, 2, 3, 4, 5). ...
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1answer
240 views

Why plants (eg. parsley) can keep vitamin C despite all the sun?

I have read that vitamin C is highly sensitive to light. So, how could parsley, for instance keep its vitamin C as it's flooded with sunlight?
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1answer
124 views

Measuring sugar content of a tree

I would like to grow mushrooms on oak trees I can harvest from my property. I've read that the best results will be when the sap is rising but the tree hasn't budded yet. The mycelium feeds on the ...
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1answer
546 views

How does a plant cutting develop roots?

Please correct me if my understanding is incorrect; I understand branch/stem, and root are composed of different types of cells. Yet in some plants (e.g. rose, bougainvillea) a cutting from the stem ...
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1answer
180 views

How does Pothos grow in only water?

The popular potted plant, Pothos aureus (or Epipremnum aureum) is happy to grow in a jar, with only water, for years. How is this possible when other plants need at least Nitrogen, Phosphorus and ...
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2answers
113 views

Is the water transpired by plants pure H₂O, or does it contain trace minerals?

I'm considering the idea of drinking water that I trap from what is transpired by trees. Interestingly, is this water a fairly (or maybe even extraordinarily) pure form of H₂O, a remarkably pure ...
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1answer
104 views

H₂S as a source of electrons for plants

The first electron source for plants was H2S, but now most modern plants use H2O as an electron source. What is the advantage of using H2O instead of H2S?
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1answer
93 views

How can GMO contaminate biologic plants?

Let consider two use cases : I am the only farmer within a 200km radius. I first grow GMO plants. A few cycles later I decide to grow bio plants, so I uproot all of the GMO plants and plant fresh ...
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2answers
515 views

What does “chlorophyll photosynthesis peak” mean in relation to photon wavelength?

When reading about how green / leafy plants work, I saw that they have chlorophyll A & B, which allow the plant to use the energy from light by capturing and transforming. When reading about ...
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1answer
62 views

Where is ATP used in Phosphorylation?

In the section describing the Calvin Cycle, under the subheading "Reduction", my textbook states that: The steps involve utilisation of 2 molecules of ATP for Phosphorylation... I could not get ...
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1answer
75 views

What is the cause of the spots on this leaf?

On a hiking trip to the Alps I found trees whose leaves showed those spots you see on the picture. I am curious about what the cause is. Higher resolution pictures of front and back side.
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1answer
919 views

Why are there more stomatal openings on the lower surface of a dicot leaf?

This causes more transpiration to occur from lower leaf surface. What's the exact reason for why are there more stomatal openings on the lower surface of a dicot leaf?
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63 views

Determining how much energy a plant takes in?

I asked a question on WorldBuilding.SE, "Are diamond berries possible?". This led to asking a question on Chemistry.SE about the amount of energy required to burn a 1 ct. diamond (−6.527kJ). The ...
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1answer
48 views

Seed Dormancy and Seed Transportation

My textbook says "As the seed matures it loses water and enter dormancy". I am confused as to whether this happens before the seeds are transported or after, and as to how seeds know to become dormant ...
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1answer
731 views

When happens when pollen grains land on the a part other than the stigma of a flower of the same species?

When happens when pollen grains land on the a part other than the stigma of a flower of the same species? Would the pollen be transported to the stigma or would it just sit where it landed and nothing ...
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1answer
310 views

If only dicots have pith, what is the foam in the middle of cornstalks?

I've heard that the only plants that have pith are dicots, because of the shape of their vascular bundle. If that is true, what is the foam inside of the corn plants, which are monocots?
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1answer
64 views

Needle-like crystals observed in wild-grape wine under microscope. Potentially harmful?

I recently crushed and strained about thirty pounds of wild grapes to ferment into wine. About a month in, I did a visual inspection of the wine under microscope to try and identify some yeast and ...