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1500 questions
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How do you design a drug to be delivered to the CNS?
I have just started reading up on structure-based methods for drug design (this is completely not my field so apologies for stupid questions that will be coming along!)
Clearly, some drugs are designed to target the central nervous system. However,…
Poshpaws
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13
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Structure of fitness landscapes in the NK model
The NK model of rugged fitness landscapes consists of $N$ sites where fitness contribution of each site depends on its state $\{0,1\}$ and is epistatically affected by $K$ other sites. When defining the model, Kauffman & Weinberger (1989) stressed…
Artem Kaznatcheev
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13
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2 answers
Do mitochondria simply automatically convert glucose to ATP?
I wonder whether there is any intelligent decision-making in mitochondria in the timing of their operation.
Do they simply begin ATP production as soon as the correct reactants are present?
Or, because they have their own DNA, do they have more…
Vass
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13
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Could an "overactive" brain increase the chances of Alzheimer's Disease?
From Raichle ME. 2010. Two views of brain function. Trends in cognitive sciences 14: 180–90:
Alzheimer’s disease (AD) is the most common cause of progressive
cognitive decline and dementia in adults. While the amyloid cascade
hypothesis of AD…
InquilineKea
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13
votes
6 answers
Why do seeds grow upwards?
Why do seeds grow upwards? Surely gravity would pull them towards the earth's core? Can anyone shine any light on this? Do seeds that are planted deeper grow more quickly.
steve bartholomew
13
votes
2 answers
Why does sexual selection evolve beautiful features?
I have a very raw understanding of sexual selection:
Say a group of females of a certain species "like" some feature of a certain groups of males; by "like" I mean some behaviour that makes this group of females tend to mate with males having this…
Camilo Arosemena-Serrato
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13
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1 answer
Do all bacterial cells have a double membrane?
I’m reading that gram positive and negative bacteria have an inner plasma membrane surrounding the cytoplasm, then a periplasmic space, then an outer membrane.
How does this compare to my general knowledge of bacterial cells having one plasma…
P...
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13
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6 answers
Why are there not two trees of life?
Life on earth started an estimated 3.8 billion years ago, very soon (in geological time) after the earth’s surface cooled to become solid and the first oceans formed. Nowadays, we believe that all living things can trace their ancestors back through…
Isky Mathews
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13
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3 answers
Why did the urinary bladder evolve?
Sure it's convenient to decide when to urinate but not essential for survival or reproduction, as I understand. But just convenience is not a drive for evolution.
Does the bladder serve any essential purpose? If not why did bladders evolve?
Dheeraj Vepakomma
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13
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Why isn’t Haemoglobin a plasma protein, rather than being encompassed by the erythrocyte?
Erythrocytes (red blood cells) are a common feature of almost all vertebrates. What evolutionary advantage do they provide in containing haemoglobin, rather than it being just a plasma protein? In fact, haemoglobin is dissolved in plasma in a few…
Polisetty
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13
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3 answers
What animal has the longest juvenile period?
I just heard the following complaint from a comedienne.
Humans are the only animal that is completely useless for the first twenty five years of life.
Obviously this is just a joke but it is true that primates and especially humans do have…
William Rosenbloom
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13
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2 answers
What are limiting factors for intron length?
For predicting genes from a sequenced genome, you need to set a maximum intron length. How long can introns get in animals? Is there some limit?
Michael Kuhn
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13
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2 answers
Is lysergic acid diethylamide (LSD) metabolized in the body?
Is LSD broken down into other compounds by enzymes or hormones? If so, at what point and where in the body does this happen? I researched several papers appearing in a google search, but unfortunately I did not understand most of it.
Max
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13
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Did researchers evolve multicellular yeast or did they just turn on multicellularity?
In this new paper "Experimental evolution of multicellularity" found via Ars Technica the researchers describe having developed multicellularity and apoptosis within 60 days from a unicellular yeast species.
Is it possible that what they have done…
Mark Probst
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Why do antidepressants have a delayed onset of action?
Why do antidepressants take so long to reach efficacy? I've read of theories about it perhaps being due to the strength of negative feedback via serotonergic and adrenergic autoreceptors during the first few weeks of treatment. What I'm looking for…
Josh Pinto
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