The study of plant life; e.g. angiosperms, gymnosperms, bryophytes, pteridophytes, and algae.

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Why do plants have green leaves and not red?

I know plants are green due to chlorophyll. Surely it would be more beneficial for plants to be red than green as by being green they reflect green light and do not absorb it even though green light ...
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1answer
74 views

Is light required for seed germination?

Is light required for germination of every seed? If not, why don't some plants require it? Is there any difference in the quality and duration of light required ? It would be interesting if someone ...
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2answers
285 views

What are the evolutionary niches differentiating an apple from a pear?

So, as far as I understand (basic) evolutionary theories, diversity is generated by "niching." That is, if there is an environmental factor that hasn't been fully used by any species to "profit" off, ...
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0answers
32 views

Why black plum has a smell so much resembling tobacco?

Why black plum has a smell so much resembling tobacco? What substance does determine it? Can it be used for tobacco replacement?
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0answers
19 views

Does amylolysis occur in vegetables if stored under 0 Celsius?

Assume that we have a plant, e.g. kale, which is prone to amylolysis if not harvested during a frost period. If it is harvested and put in a household freezer, such that it is frozen solid slowly ...
4
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2answers
129 views

Plant identification?

Can anyone identify the plant below? It's in a backyard in Pennsylvania, and the photo was taken today.
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1answer
68 views

How many plants are needed to survive in an airtight chamber?

How large a garden do you need if you are to survive on them producing enough oxygen in a closed chamber? And which are the most effective plants?
5
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1answer
413 views

How do individual plants adapt to changes in temperature?

If you grow a plant from seed in your nice warm house, then plant it out in your temperate garden, it will stop growing for a while, possibly die, and if not, subsequently resume growth. Standard ...
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0answers
30 views

Why is this dry pepper fruit still “powered”?

Check out this photo of my pepper plant this cloudy morning: (click for full res) Usually (and this can be seen on 2 and a half of the 4 fruits in this pic) the fruits are "disconnected" from the ...
2
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1answer
133 views

Independence of Light independent reaction in photosynthesis?

Inspired by a question asked to me by a classmate, I have the following question about Light-independent (dark phase) reactions in photosynthesis:- Let us suppose an algae sample was exposed to ...
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1answer
62 views

Identification of this plant?

Photographed in Rocky Point, Mexico. Any ideas about this plant? Thank you!
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1answer
29 views

Ribosomes and DNA in chloroplast

Are there multiple copies of circular DNA and membrane bound ribosomes IN CHLOROPLAST ? Are polysomes found in them ?
2
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1answer
73 views

Can a plant be programmed to produce any arbitrary object?

I'm wondering if a plant can be programmed (by modifying its genes) to grow into any shape that it's programming instructs. I understand that a plants genes are its instructions of how to convert the ...
5
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1answer
1k views

How does plant grafting work?

Plant grafting is a process whereby a piece of one plant is inserted into another and results in a change of the original plant. For example, grafting a piece of a lemon tree into a bitter orange tree ...
5
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1answer
136 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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1answer
208 views

How to determine if a plant is autotrophic or heterotrophic?

How do you determine if a plant is autotrophic or heterotrophic, and are there any traits in particular that can be used to classify species? As two examples, how should Melampyrum pratense and ...
10
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2answers
119 views

Why do cucurbits produce so much fluid when their stems are cut?

When carrying out some germination tests on species in the Cucurbitaceae, I notice that young plants of this family produce a lot of clear fluid when they are dissected. Most plants I dissect do not ...
4
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2answers
250 views

Why is the floral biodiversity of grazed grassland higher than that of mown grassland?

I have collected some data to compare the biodiversity of a field in which the plagioclimax is maintained by machine mowing with a field in which the plagioclimax is maintained by sheep grazing. What ...
11
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3answers
257 views

Most suitable biodiversity index

I am conducting an investigation into the effect of two different grass management techniques (grazing vs. machine-mowing) upon floral biodiversity. I have collected my data and now need to process ...
5
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1answer
60 views

Shade-loving Plants

In shade-loving plants, the light compensation point is reached at low irradiance because: A. Leaves have more chlorophyll per reaction center B. These plants have greatly reduced respiration rates ...
3
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1answer
334 views

Family tree for edible plants?

I am looking for a family tree for plants, particularly veg / herbs / fruit. Something similar to: If it could be slightly less technical than all the Latin ...
4
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1answer
98 views

Function of papain in papaya

I know that papain is a proteolytic enzyme present in papaya. It is often used to tenderise meat. What is the function of papain in papaya? Is papain sweet? Does it function as an antibiotic?
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0answers
140 views

Change of phase from juvenile to adult in plants

I tried googling this but couldn't get much information on this. Most of the articles were about induction of flowering. I am more interested in knowing what factors influence the conversion of ...
0
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1answer
108 views

Organelles present in sieve tubes

I know that sieve tubes do not have ribosomes, nuclei and cytoskeletal elements. What other organelles does it not have? Does it have a cytoplasm?
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0answers
24 views

Presence of lignin and pectin

Are lignin and pectin present in primary cell walls or only in secondary walls? The sources available on google are confusing?
3
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1answer
53 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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2answers
3k views

Did animals evolve from plants?

Did animals evolve from plants? Did animals' ancestors have chloroplasts in their cells?
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1answer
126 views

What is this awesome plant, which can close its leaves when touched?

I came across this video on Facebook where a plant closes its leaves when touched. Unfortunately the video does not mention the name of this awesome plant. What's the name of this plant, and where ...
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0answers
34 views

Root hair formation in Arabidopsis

In arabidopsis, 2 cell types arise in the root epidermis : root hair cells and hairless epidermal cells. The immature epidermal cells that are in contact with 2 underlying cells of root cortex ...
3
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1answer
132 views

Plant a whole fruit or only seeds?

I'm trying to figure out whether it is better for the plant to reproduce by planting its whole fruits with seeds inside them, or picking the seeds out and planting them without the fruit. In my case ...
7
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1answer
226 views

What biological processes cause leaves to change colours in Autumn?

I am curious to learn what are the biological mechanisms that cause leaves of deciduous plants to change colour? What happens to the chlorophyll? What environmental phenomena (temperature/air ...
6
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1answer
318 views

Photosynthetic Pigments vs. Chloroplasts

What is the difference between Photosynthetic Pigments and Chloroplasts? I know plants have both but Prokaryotes (Bacteria and Archeae) only have the former.
8
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1answer
90 views

What are the variables that control/influence the color of oranges(Citrus sinensis)?

I hear that Oranges cultivated in tropical areas of the world tend to be greener when ripe, is that correct? Even the same type of Orange differs in color if cultivated in California or Florida. I ...
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1answer
82 views

Do non-green flower colors have any functional interactions with the sun?

I always hear the pseudo-evolutionary claim "plants are green because they need to use red and blue light". If this premise to my question is true, What (if any) other functional relationship occur ...
2
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2answers
72 views

Tree census data for Sweden/Scandinavia?

Is anyone aware of any attempts to count or approximate the number of trees there are in Sweden or Scandinavia? I have a small popular science side project for which this would be useful
0
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1answer
37 views

What determines the strength of a tree

What determines the strength of a tree. A morphologically strong looking tree found broken down at trunk. can we determine the strength/ life of a plant
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1answer
97 views

What is Growing on These Tree Leaves?(Image)

I found a seemingly diseased tree when I was out playing tennis yesterday... What is growing on this tree leaf? Is this a disease? If so, is it contagious? I have zero knowledge in botany, but I'm ...
7
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1answer
90 views

Do any plants exhibit hormonal changes similar to puberty?

Just what the title states. Are there any plants/trees that exhibit a growth spurt at a definite interval after the shoot appears?
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2answers
173 views

Change in conditions of an ecosystem lead to change in organisms

Let's think about the slash and burn method and its effects on the ecosystem. Cutting down trees that rise all the way up to the canopy would expose the plants at ground level to more light, so would ...
3
votes
1answer
67 views

What happens if we continuously stimulate a mimosa plant?

I know there is some mechanism in humans by which we start to ignore a certain stimuli if it persists for a long time (e.g., we don't feel our shoes all the time !). Can the same thing happen in ...
8
votes
1answer
116 views

How would a warm winter affect maple sap production?

The past winter (2011-2012) was warmer than usual. Trees are normally tapped in late February when the daily maximum temperature goes above freezing. However, assuming that there have been ...
2
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1answer
489 views

Why does freshly cut grass smell like a watermelon?

I found that, when I smell watermelon aroma outdoors, someone nearby has mowed the grass. Is there an underlying basis?
2
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2answers
156 views

Why doesn't human consumption of plants cause infectious diseases the way consumption of animals can?

At first I want to clarify that I do know that there are naturally poisonous plants and plants that can hold radioactive stuff or toxic material from the environment. What I mean by "diseases" (I ...
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2answers
97 views

Will climate change affect flower population?

There is a flower population elevated 1000 meters above sea level. If climate change causes a 12 degree C increase in temperature over the next 10 years, what will happen to the flowers?
13
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2answers
3k views

How will rising carbon dioxide levels in the troposphere affect photosynthetic producers?

Much discussion has been had about the affects of climate change on plantlife, but how will rising carbon dioxide concentrations affect the photosynthetic process itself? Since CO2 is a reagent in ...
3
votes
1answer
86 views

What are these stars in my microscopic image?

I see this very curious patterns on the sun-facing side of a jasmine (probably) leaf - visible with a makeshift microscope (about 50x) What are them? Pores? Are there other plants with similar ...
6
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1answer
786 views

How do lilies sense day and night and open and close their flowers?

We have lots of lily flowers inside our garden. Their flowers are open in day and closed in night. How do lilies sense day and night and open and close their flowers?
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0answers
23 views

Is there a database of pollen-seed distances across plant species?

I was enjoying Richard Smith's excellent answer to this question, and wondered: If you consider the pollen/seed distribution range to be plant locomotion, is there a database that compares these ...
6
votes
1answer
71 views

What mechanisms tell temperate trees when to drop leaves?

I've been looking around and cannot find a definite answer on what it is that tells trees to change their metabolism and drop leaves. I see that such activity is called Deciduous. What interests me ...
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1answer
180 views

How do animals/plants change for each season?

The question pretty much sums it up. How do animals/plants change for each: Spring, Summer, Autumn, and Winter? A detailed explanation on distinct behaviour and appearance changes would be nice.