4
votes
2answers
239 views

How do insects such as crickets circulate blood through their antennae?

Some insects, like the crickets pictured below, have such slender antennae it seems no blood could fit. How do they get blood through their antennae?
2
votes
1answer
91 views

Structure of RAP Antibodies (Specifically RAP-5)

[EDIT] - Have just found not one but two papers that address my structure problem. However they concern RAP-1A, so I guess my question is now what is the difference in structure and function of ...
9
votes
1answer
1k views

What's the effect of oxygen deficit on plants?

As I know all cells require oxygen. So my question is how efficiently can plants operate in no-oxygen atmosphere? Do all plants produce enough oxygen for themselves? Can they consume their own oxygen ...
8
votes
2answers
386 views

What does “nesting failure” mean?

According to the Wikipedia article on swans, swans are mostly monogamous but may sometimes separate, particularly after a "nesting failure". What "nesting failure" may mean is not entirely clear to ...
6
votes
1answer
84 views

Is there a tool to find the action of an enzyme in a metabolic pathway?

Is there any tool to search the biochemical action of a particular enzyme in a metabolic pathway of an organism? In other words, how can I find if enzyme "E" is involved in the metabolic pathway for ...
13
votes
2answers
552 views

Does testosterone increase female sexual behavior?

According to my lecture notes testosterone generally increases sexual behavior. Given that it's generally thought to be the male hormone I'm not quite sure whether they mean that it also increases ...
10
votes
1answer
164 views

(How) does coppicing fundamentally alter tree growth?

I am interested in adding the ability to model coppice tree production to a model of perennial crops (Miguez et al 2008).. Implementing the biomass pools and allocation parameters required for tree ...
12
votes
3answers
301 views

What is Curved DNA?

CbpA is DNA binding protein found in E. coli and binds non-specifically to curved DNA (Cosgriff et al., 2010), when the bacterium is in a static phase of growth. The use of "curved DNA" confuses me. ...
7
votes
1answer
2k views

Why does Rigor Mortis occur after death?

After someone dies they become stiff, this is termed Rigor Mortis and happens because the cells run out of ATP (I think). But why do the cells need it to remain flexible?
9
votes
4answers
2k views

Why can cones detect color but rods can't?

I don't know if this question applies to only humans but why can cones see much greater detail than rods? Is it possible to have a rod that can detect light intensity and color?
4
votes
2answers
128 views

Does age affect the frequency of flatus?

Is there any relation between age and the frequency of flatus? I often have this feeling that older people f*** more often than younger ones. Is this feeling scientifically correct?
13
votes
2answers
2k views

What effect does vortexing have on a fluid sample that simple mechanical shaking does not?

Some protocols call for fluid samples to be mixed with a "vortexer" on the high setting. What effect does the vortexing have on fluid samples that mechanical shaking does not? Does it shear long ...
13
votes
3answers
2k views

How does the human body metabolize gasoline?

A Chinese man has been drinking gasoline to relieve his pain for 25 years. How does the human body metabolize gasoline? Also, what are the side-affects to gasoline?
10
votes
2answers
271 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, ...
3
votes
1answer
163 views

If only dicots have pith, what is the foam in the middle of cornstalks?

I've heard that the only plants that have pith are dicots, because of the shape of their vascular bundle. If that is true, what is the foam inside of the corn plants, which are monocots?
8
votes
2answers
2k views

How do the lungs act as a sieve to trap blood clots?

Does anyone know? I'm curious to find out as my human anatomy and physiology book doesn't go into much detail on how the lungs function as such
8
votes
1answer
535 views

If the xylem of a woody plant is composed of dead tissue, how does sapwood become heartwood?

If the xylem of a tree is composed entirely of dead tissue, then that means the sapwood is dead. If so, how does it transform into heartwood, and what starts the process?
7
votes
1answer
212 views

Could an animal with an open circulatory system survive in a near-zero gravity environment?

An animal such as a crayfish relies on gravity to keep its circulatory system running. If it is turned upside down, the gravity works against the system, suffocating the animal. Now if, instead of ...
4
votes
1answer
2k views

What is the role of acetylcholine in blood pressure regulation?

What is the role of acetylcholine in the cardiac cycle and in blood pressure regulation?
6
votes
1answer
115 views

What is the number of cells in a line of a fingerprint?

I have been reading a little about the size of cells and was curious as to how small they really were. I have noticed that on my finger, the outlines of the fingerprint are made up of thin lines. In ...
6
votes
3answers
285 views

How does “be altruist to those who are similar to you” evolve?

There are many cases when people commit altruism. One is relationship. I am willing to die for 2 of my children or 8 nieces, say an evolutionary psychologist. Another is reciprocal altruism, which is ...
6
votes
1answer
4k views

What would cause bands to appear lower on a nonreduced SDS-PAGE gel?

I have a protein gel and I'm comparing the reduced with the non-reduced gel. On the reduced gel, I have a few shorter bands but these bands appear with low intensity. In the non-reduced gel, I'm ...
4
votes
1answer
330 views

What's the distinction between a tetrad and a synaptonemal complex in meiosis?

What's the distinction between a tetrad and a synaptonemal complex in meiosis? Are they synonyms? I ask because the concepts seem very closely related, but it seems like there may be a subtle ...
7
votes
2answers
348 views

How do white Caladiums perform enough photosynthesis to support their mass?

In some white caladiums, there is less than a square inch of green space spread over the whole leaf. How do these plants perform the photosynthesis necessary to support the large leaves, the roots, ...
6
votes
1answer
163 views

Is there an enzyme for the transformation of the hydroxyl group?

I would like to know, is there any enzyme which does the transformation of hydroxyl group to any other functional group using the enzyme. The substrate is aromatic hydroxyl group. Product should not ...
5
votes
1answer
453 views

What are the various types of protein-protein interactions

I understand there are a number of protein-protein interactions, but what types of interactions exist? and what are the characteristics of them?
7
votes
1answer
204 views

Is there a biological basis for different accents?

How did accents first develop? Was it climate dependent? or was it a social behavioural issue? Is there any biological reason for the development of accents?
4
votes
4answers
634 views

Which came first: The Chicken or the Egg? [closed]

Has there been any serious scientific inquiries into answering this age old question?
7
votes
1answer
233 views

What causes light to be brighter in the corner of the eyes?

I have noticed when in a dark room light and color seem to be brighter and more intense in the corner of my eyes. For example the light that comes from my digital clock seems like a dark pink when I ...
5
votes
1answer
502 views

Genetic carrier Pedigree of Recessive Traits

A human male and female couple with normal colored ears discover that, in both of their families, their fathers (who have normal ears) each had siblings with red ears. Red ears is a rare autosomal ...
17
votes
2answers
1k views

Which organism has the smallest genome length?

Which animal/plant/anything has smallest length genome?
8
votes
2answers
237 views

What's the name of this bird?

This morning I saw a bird that I have never seen before. Since it was quite big, I'm very interested in knowing its name. The bird was quite big, at least 2-3 times of a common blackbird. The wings ...
7
votes
3answers
117 views

Free Radicals for aging

From my understanding free radicals play a slight role in ageing. In what ways are they so damaging, and can a restricted diet reduce production of free radicals?
7
votes
1answer
971 views

Single hormone opposite effects

Often, a smooth response to a hormone means that some processes must be sped up and others must be slowed down. How can a single hormone have opposite effects like this?
0
votes
1answer
79 views

If inhibiting S6 kinase decreases protein translation, then could inhibiting S6 kinase could possibly slow down long-term potentiation in neurons?

From http://en.wikipedia.org/wiki/P70S6_kinase... Phosphorylation of S6 induces protein synthesis at the ribosome. P70S6 kinase is in a signaling pathway that includes mTOR (the mammalian ...
4
votes
0answers
37 views

RHEB senses amino acids in order to recruit mTOR. Do we know if RHEB is more sensitive to some amino acids (like methionine) than other amino acids?

See http://www.ncbi.nlm.nih.gov/pubmed/21157483 for the full paper describing the process of how RHEB recruits mTOR. We also discussed this in Matt Kaeberlein's class yesterday and I posed this ...
2
votes
1answer
127 views

What are the effects of combining rapamycin with dietary restriction?

Are the effects additive or subadditive? In many ways, rapamycin acts like a CR mimetic, but even CR can only go so far.
5
votes
1answer
98 views

In what ways, if any, does administration of rapamycin *not* mimic calorie restriction?

Numerous sources like this say that rapamycin increases lifespan. And mTOR antagonism appears to be a large part of this (mTOR antagonism also appears to be a large part of calorie restriction's ...
13
votes
1answer
191 views

How does herpes (HSV) infection suppress HIV?

HIV compromises the human body to defend against infection. Yet people who are infected with herpes are at less risk of developing AIDS. How does this work?
8
votes
2answers
345 views

Why is blood pressure higher the more distal an artery is?

Why is blood pressure generally higher in more distal arteries?
8
votes
3answers
579 views

Why is methylcellulose used in pharmaceuticals?

Why is methyl cellulose used as a pharmaceutical excipient? Is it due to certain chemical properties? What are the reasons for relying on the chemical properties of methyl cellulose?
11
votes
2answers
301 views

Why do pandas have a high probability of giving birth to twins?

According to the BBC documentary "Wild About Pandas", about half of panda birth result in twins. Why do they have such a high probability compared to other mammals? What factor(s) control that ...
12
votes
2answers
139 views

How to decide which is the correct scientific name for a particular species

To start with, I am not a person having sound knowledge in biology. When I started my search for phyto-chemicals in a particular family in the plant kingdom, I got confused. The scientific papers use ...
14
votes
2answers
223 views

Can methylation from DNA get copied to RNA during transcription?

Methylation on gene-body and 3'UTRs if copied to mRNA can potentially regulate post-transcription modifications or expression regulation. But I'm not sure if they are maintained after transcription or ...
7
votes
1answer
75 views

Is there a standard format for plant community composition data?

FIA has a nice database of forest Inventory data, this would be great except that it does not seem capable of handling data from non-tree species (e.g., grasslands, wetlands). Is there a standard ...
11
votes
1answer
261 views

What is the mechanism that directs myosin walking?

Myosin, dynein and kinase all "walk" towards specific ends of the microtubule or actin filament they are on. I'm most familiar with the walking mechanism for myosin, where ATP fuels conformal changes ...
4
votes
1answer
196 views

Automatic cropping of collimated digital X-ray images

Do you have any suggestions for a library which offers an algorithm to crop digital X-ray images automatically? We receive full-size images (43x43cm) from a detector, independent of the collimator ...
8
votes
2answers
189 views

Why do animal teeth get darker if exposed?

I was wondering why the teeth of cats (And dogs, as far as I know, plus possibly some other animals or even humans) get darker if they are exposed to air / light? Example: (See the lower end of ...
4
votes
0answers
39 views

Serological assays not detecting native proteins

Is there anyone out there who has done much work with serological assays? We have antiserum for a manufactured viral protein but no luck so far getting it to detect native protein (unless today's ...
8
votes
1answer
183 views

What is the maximum potential sucrose concentration of plant sap? What keeps plants below this potential?

I am interested in identifying the maximum potential dissolved sucrose (%w/w) that plant sap could have, and which (biological, physical, chemical) factors constrain the observed sucrose ...

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