jkadlubowska
  • Member for 9 years, 4 months
  • Last seen more than 1 year ago
How many people are required to maintain genetic diversity?
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25 votes

Actually it is a very important question for laboratory animals (and, I imagine, endangered species) and was calculated to be 25 couples. With any number of animals (including humans), there is ...

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Do animal cells have vacuoles?
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16 votes

They are both right. Animal cells do have vacuoles, but they are smaller, larger in number (plant cells usually have just one or a few large vacuoles) AND serve a somewhat different purpose than ...

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Why do most breast cancers occur in women?
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10 votes

Yes, this is mostly about estrogen. Most breast cancers rely on endogenous estrogen to sustain proliferation. Some general reading: Cancer Medicine, Chapter 18 More in-depth reading: Endogenous ...

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Are there any solitary species of ant or termite?
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8 votes

I do not know of any solitary ants, but there are species that form very small colonies. One such species is Jerdon's Jumping Ant (Harpegnathos saltator). They usually live in colonies smaller than ...

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Why is Turner syndrome rarer than Klinefelter syndrome?
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6 votes

First of all, they are not caused by the same mechanism. They are both aneuploidies, but the mechanism is different. Turner syndrome happens when one of the gametes (most commonly father's) lacks a ...

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Is there any complex organism that is both autotroph and heterotroph?
6 votes

For example sundews are plants (so autotrophic), but they "hunt" for insects to get additional nutrients, e.g. nitrogen. As far as I remember the nitrogen is the main reason for eating other organisms ...

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Why Do Ruminants Require A Multi-Compartment Stomach To Digest Food?
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5 votes

There is more difference than just the parts of plants that are eaten. Two of their stomachs - rumen and reticulum are not used for digesting food at all. Multiple rounds of chewing and mixing with ...

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Is there any evidence that a virus can modify human evolution
5 votes

The simplest example, that I can recall are the flu pandemics. The 1918 pandemic is the first to be described because of its severity, but quite possibly not the first in human history (see for ...

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Are some non-coding RNA spliced?
4 votes

Do you call ribosomal RNA non-coding? rRNA is spliced both in prokaryotes and eukaryotes.

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Dinuclei cellular mechanism
3 votes

It depends on the kind of organism. When the cell with two nuclei will try to go through mitosis, the nuclear membranes will fragment, releasing all genetic material to the cytoplasm, where it will ...

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Pseudosexual reproduction
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3 votes

Generally, all diploid species pass through a haploid phase in their life. This is called the alternation of generations and the cycle may be presented like this: Commonly we see organisms that spend ...

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How are long time periods measured in biological systems?
3 votes

Though chemical concentration seems implausible, at the deepest level it is the cause. On a smaller scale - how does a eukaryotic cell know when it is ready to divide? By the concentration of ...

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Botulinum Toxin
2 votes

The short answer is: unless you burn the sample completely to ashes, you cannot be sure you destroyed all BT particles. Denaturation is a naturally occuring process and it works pretty much like ...

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In a human, what non-germline cells have the highest/lowest mass?
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2 votes

Large cells: adipocytes, the cells that store fat are possible the largest in humans, because after puberty they rarely divide and just enlarge if a person gains weight. A typical adipocyte is about 0....

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DNA as an acid?
2 votes

DNA is made of three types of molecules in equal proportions - basic nucleotides, sugar deoxyribose and acidic phosphate groups. The bases are on the inside of the helix and partly hidden from the ...

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What is the inbreeding coefficient for the female offspring of a sib-mating in a haplodiploid system?
1 votes

From the same article on wikipedia: The inbreeding is computed as a percentage of chances for two alleles to be identical by descent. Now let's draw a family tree for such mating and sign chances ...

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An unexpected mushroom in my garden
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1 votes

Thanks to MCM's advice I know for almost-certain that this is Lepista personata.

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Fetal development, gastrulation and embryonic disc
0 votes

The second picture does not show human gastrulation. Your source talks about the development of yolk sac in human embryos, and does not claim it depicts gastrulation. In human embryos gastrulation ...

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Can I figure out the identity of my grandparent from this information?
-2 votes

On a high-school level you are right. Still, the answer to your question is no. As you may have already noticed, nothing in reality is as simple as schools tell us. Eye colour is generally determined ...

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