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

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Why we have no enzyme to digest cellulose?

As we know, cellulose is the most abundant polysaccharide in nature. Why don't we have any enzyme to digest cellulose?
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1answer
70 views

How are Raunkiær's plant life forms viewed today?

At the beginning of the 20th century, Raunkiær proposed a typology of plant life-forms based on where they bear their buds, roughly as: cryptophytes: belowground hemicryptophytes: at the surface ...
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1answer
62 views

How much cost would artificial pollination add to common products (fruits etc.)?

I've read about ecosystem services and their possible valuation - statements like "honeybee pollination service in the US is worth 1.6 billion dollars". Is data available on how this would affect the ...
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2answers
443 views

What does dominant generation mean

In my texbook it is written that for non- vascular seedless plants the dominant generation is the gametophyte as the gametophyte generation is larger and longer lived. Is the criteria for dominant ...
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1answer
148 views

Scientific name for the union point of a plant stem and root

Is there a word that describes the meeting point of a plants growing stem and its root? Is this the same term for aerial roots above soil level?
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1answer
70 views

Artificial Propagation and it's relation to asexual reproduction

I know that asexual reproduction is also called vegetative reproduction. However I do not understand it's relation to artificial propagation. Is it a technique used for asexual reproduction (the ...
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1answer
66 views

Terms related to megasporogenesis

Well, I am not able to understand the exact difference between megasporocyte and archesporium. Also I'm not quite able to get, how or precisely from where do these arise? Please help.
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0answers
16 views

Artificial propagation and Asexual Reproduction [duplicate]

Am I right when I say artificial propagation techniques provide the means for plants to reproduce asexually? Also, is my understanding of asexual reproduction and artificial propagation correct: ...
0
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1answer
40 views

Seed Germination

Is my understand of how seed germination comes to be and what it entails correct? Seed germination: As the seed matures it loses water and enters dormancy (a state in which it’s metabolic processes ...
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1answer
32 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
84 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
335 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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2answers
139 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
78 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
558 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
36 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 ...
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1answer
69 views

Identification of this plant?

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

Ribosomes and DNA in chloroplast

Are there multiple copies of circular DNA and membrane bound ribosomes IN CHLOROPLAST ? Are polysomes found in them ?
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1answer
88 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
2k 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
154 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
263 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
127 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 ...
11
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3answers
279 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 ...
3
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1answer
385 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
127 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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1answer
164 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?
3
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1answer
57 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
4k views

Did animals evolve from plants?

Did animals evolve from plants? Did animals' ancestors have chloroplasts in their cells?
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1answer
148 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
35 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
160 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
326 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
357 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
92 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
87 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
75 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
42 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
116 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
106 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?
2
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2answers
194 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
76 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 ...
9
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1answer
119 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
637 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
212 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 ...
3
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1answer
99 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
973 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
25 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
87 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
225 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.