238
votes
Why are so few foods blue?
Short answer
Blue color is not only rare in edible organisms - Blue color is rare in both the animal and plant Kingdoms in general. In animals, blue coloring is generated through structural optic ...
- 52.6k
130
votes
Why are so few foods blue?
Although @AliceD's answer is a great simple demonstration of the rarity of blue in our natural world, there's likely a more nuanced/technical reason.
Short answer
Blue light was the most available ...
- 30.3k
81
votes
Accepted
What's up with this leaf?
That is the work of a leaf miner. A leaf miner is the larval stage of an insect that feeds on the inside layer of leaves. Notice how the galleries (tunnels) start small and then get larger as the ...
- 7,703
57
votes
Accepted
Examples of plant families that contain species that are safe for human consumption and species that are poisonous to humans?
The most classic example if you want to win this argument would be the family Solanaceae.
Also referred to as the Nightshade family, it includes the deadly nightshade or Atropa belladonna and many ...
- 46.5k
51
votes
Accepted
Why does cutting onions cause tears?
Interesting question! The cause of tears and itching is the chemicals produced by onion (Allium cepa). Lets go into some details.
Onions, coming from the family Liliaceae (also containing garlic, ...
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45
votes
If plants benefit from carbon dioxide, why is car traffic something bad?
There are at least two separate answers to your question. First, with respect to plants needing CO2, they have evolved to deal with the limited amounts of CO2 normally in the atmosphere. That's ...
- 3,653
43
votes
Accepted
Are these microscopic star-like structures on a dead leaf some sort of organism? If so, which one?
These are stellate ("star-shaped") [and possibly peltate ("borne on a stalk")] hairs ("trichomes") of the leaf itself.
From Harris & Harris's (2001) ""...
- 30.3k
39
votes
Is the amount of the soil reduced when plants grow?
The vast majority of the mass of a plant is carbon-based which is obtained directly from the air via photosynthesis. So trees are, in a loose sense, solidified air!
And most of the mass that comes ...
- 451
37
votes
If plants benefit from carbon dioxide, why is car traffic something bad?
Exhaust gasses from combustion contain many compounds in addition to CO2.
Some of them under the right circumstances‡ can be of limited benefit to some plants, but others such as ozone are damaging ...
- 5,613
36
votes
Examples of plant families that contain species that are safe for human consumption and species that are poisonous to humans?
The Apiaceae family has many edible plants including carrot, parsley, fennel, celery, and parsnip, and has toxic plants such as poison hemlock, fool's parsley, and giant hogweed.
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33
votes
Would fewer cows mean less methane emission?
Couple of thoughts:
(The OP's article is a low quality source of info with either an interview taken out of context or an inappropriately vague or under-informed interviewee. Reasons why will become ...
- 30.3k
32
votes
Accepted
What is the name of this red plant?
This is the "Acer palmatum" or Japanese maple, which shows a wide variety of different leaf forms (from here):
Specically you found "Acer palmatum dissectum 'Red Dragon'", for more information look ...
- 52.5k
29
votes
Examples of plant families that contain species that are safe for human consumption and species that are poisonous to humans?
Both the cashew and poison ivy are members of the Anacardiaceae family.
- 391
28
votes
Accepted
Can plants suffer from CO2 poisoning?
Short answer
It has been shown that plants may already suffer from doubling the atmospheric CO2 concentration from 340 to 610 ppm, something that might happen during the next hundred years or so based ...
- 52.6k
26
votes
Accepted
Where does moss come from?
Short answer
Moss plants form spores; minute, invisible, typically one-celled, reproductive units that are carried off by the wind and into your pots.
Background
Mosses belong to the Bryophytes. ...
- 52.6k
22
votes
Why do plants have green leaves and not red?
I know this question was asked and answered a number of years ago (with many great answers), but I couldn't help but notice that no one had approached this from an evolutionary perspective (like the ...
- 30.3k
22
votes
Why does cutting onions cause tears?
This is due to a lachrymatory agent called as syn-propanethial-S-oxide.
The process goes as follows:
Lachrymatory-factor synthase is released into the air when we cut an onion.
The synthase enzyme ...
- 4,836
21
votes
Do strawberry seeds have different DNA within the same fruit?
Strawberry seeds will all have different DNA.
It is standard for seeds to have different DNA, even those contained in the same fruit. Normally, the egg cells held in the ovule ultimately come from ...
- 2,859
20
votes
Is a walnut a nut or a drupe?
Short answer
Walnuts are classified both as nuts and drupes ('stone fruits').
background
According to University of Wisconsin - Madison, Department of Botany , hickory and walnut can be classified ...
- 52.6k
20
votes
Accepted
Which strange fruit is this?
This appears to be a jackfruit. Jackfruit are a large, tropical fruit, commonly reported as smelling similar to banana.
- 3,314
20
votes
What's up with this leaf?
This leafminer is a moth in the genus Phyllocnistis (Gracillariidae). If you knew what plant the leaf came from, the moth could probably be identified to species. The marginal leaf fold at lower right ...
- 301
19
votes
Accepted
If plants "alternate generations" between sporophytes and gametophytes, why don't we say the same of humans?
The big difference is that in humans, there is no mitosis in the haploid phase.
There are three terms that are important here:
Haplontic: Most of the life is spent in the haploid phase
Diplontic: ...
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19
votes
Accepted
This looks like it was somebody’s home - but who?
That looks similar to the dried fruit of Echinocystis lobata (wild cucumber), which grows throughout New York. The fruit is about the right size (~3 cm) and shape, whereas the best alternative I can ...
- 5,613
18
votes
Accepted
Does anybody know which plant (or tree) is this?
The plant scientific name is Prosopis juliflora. It is widely found in our country (India) which is a major problem because of its impact in agricultural land. It can withstand any harsh climate also.
...
18
votes
Can plants suffer from CO2 poisoning?
It depends upon the plant species.
As explained in Algae thrive under Pure CO2 Nature 227, pages 744–745 (15 August 1970):
Cyanidium caldarium (an algae found in Yellowstone National Park) ...
- 756
18
votes
Is it scientifically sound to pool repeated measurements?
If you use the configuration on the left, your variance across tubes reflects variance between individuals.
If you use the configuration on the right, your variance across tubes reflects primarily ...
- 46.5k
Only top scored, non community-wiki answers of a minimum length are eligible