8
votes
1answer
886 views

How to clone and sequence a gene transcript of unknown sequence?

How might I go about amplifying a gene transcript (mRNA) from animal tissue of which little is known about the genome? In some applications, I have used reverse transcriptase PCR to amplify all mRNA ...
7
votes
1answer
133 views

Does the MS2 RNA binding protein have any translational repression effects?

Reposted from Quora: http://www.quora.com/Does-the-MS2-RNA-binding-protein-have-any-translational-repression-effects I'm thinking of the MS2 protein binding to its RNA hairpin target. Would the ...
5
votes
1answer
100 views

What is the distance between the 3' 18s rRNA (the Kozak consensus sequence) and the A-site of eukaryotic ribosomes during protein translation?

Reposted from Quora The Kozak sequence is shown to be important in translation initiation, and the A-site is the anti-codon recognition site. If the distance is not known, how could I find out what ...
7
votes
1answer
8k views

What is the difference between “dikaryotic” and “heterokaryotic” states in the sexual lifecyles of fungi?

Many fungi undergo a reproductive phase in which more than one genetically distinct nuclei (from 2 separate mating types) is present within the same cytoplasm. In the Ascomycota and Basidiomycota, ...
11
votes
1answer
108 views

To which distinctions does the term “hymenoptera” refer?

Hymenoptera is an order of insects that includes bees, ants, and wasps. A quick search gives the following etymological analysis of the term hymenoptera. hymen (membrane) + pteron (wing) Does ...
13
votes
1answer
3k views

Why does Penicillin only affect bacterial cell walls

I was quite fascinated by the feature Should Science Pull the Trigger on Antiviral Drugs—That Can Blast the Common Cold? in this month's Wired magazine. They explain that Penicillin is effective at ...
15
votes
5answers
8k views

Origin, or source, of rhesus negative in human blood

This is my first post here, so please be gentle. I recently learned that I have Rh- blood (I'm A-), and was idly looking into blood types on Wikipedia. I was surprised to find that relatively few ...
7
votes
1answer
63 views

Which factors besides the thermodynamic stability are important for the hairpin in intrinsic transcription termination?

Intrinsic termination (rho-independent) relies on a stable hairpin with a subsequent uridine repeat. The common explanation on how these sequences cause the termination of the transcription are based ...
26
votes
1answer
464 views

How does a cell know its size?

Cells come in all sorts of sizes. How do they regulate their cell size to the point where similar cell types have a fairly mono-disperse size distribution? Reasked from ...
7
votes
1answer
92 views

Providing small molecules to cells on a filter plate

Lets imagine that I have mammalian cells that I've immobilized on a filter. Now I want to keep providing small molecules to these immobilized cells without resolubilizing the cells. The caveat is ...
10
votes
1answer
609 views

Do larger multicellular organisms have an increased risk of mutation and thus cancer?

So I was thinking that if each cell has P(X) of becoming cancerous, then the chance of cancer is 1-((1-P(X))^n) where n is the number of cells in the organism. Since larger organisms have more cells ...
12
votes
3answers
697 views

Is the appendix a vestigial structure in all vertebrates?

In humans the Appendix is a vestigial organ. Does it serve no apparent purpose in all the vertebrates that have one?
7
votes
1answer
438 views

How do fungi react to being grown in a tissue culture?

I know how plant cells and animal cells react to being cultured and grown this way, but what about mushrooms? Would they respond like plants, and result in embryos growing off the mass? Or does the ...
6
votes
1answer
186 views

Are there any other animals that become attached to a non-living object?

Do any animals become psychologically attached to any non-living object that is not useful to the animal for any of its physical needs, like some children do to stuffed animals? Some children are so ...
14
votes
3answers
860 views

What evolutionary explanations are there for death?

I know death and cancer doesn't hurt humans' reproductive success. It's not helping either. Why do we die? Why dying humans (all of us) are common? What's the point of dying?
8
votes
1answer
543 views

What conditions are necessary for HPL (human pancreatic lipase) to activate?

What conditions are necessary for human pancreatic lipase to activate? Is there an optimal temperature or pH? How quickly does it take effect?
9
votes
1answer
271 views

Can fruit tissue be cultured and grown independent from the plant?

Can fruit tissue be grown in a tissue culture as is done to other plant tissues? From the answer to this question, I learned that fruit is alive. Could it be possible to manufacture fruit products ...
7
votes
1answer
1k views

Can any plant regenerate missing tissue?

I have not yet found a plant that, when an insect eats a hole in one of its leaves, it can regenerate the lost tissue. Many plants will grow a new stem if the old one is cut, but it is not a perfect ...
8
votes
1answer
156 views

What do we know about LUCA?

All life on Earth (bacteria, archaea, eukarya) is thought to have evolved from a common ancestor, or last universal common ancestor (LUCA). What do we know about the characteristics of LUCA based upon ...
8
votes
1answer
231 views

How long does it take for E. coli to shift feedstocks?

With our fermentations we're noticing that it takes an appreciable amount of time for E. coli (K12 variant) to change from being metabolically streamlined on amino acids to being metabolically ...
3
votes
1answer
308 views

Predicting progeny of recessive mutations using recombination

I was asked this question on a test and got it wrong, but I'd like to know how to do it. The answers are shown in the blanks below: You are studying two recessive mutations in the fruit fly D. ...
6
votes
2answers
1k views

Basic Amino Acid Residue Binding Mechanism to DNA

I understand that many protein DNA binding domains bind to DNA via basic residues such as Arginine and Lysine. But what is the mechanism used to bind to DNA and where on the DNA would these residues ...
4
votes
1answer
11k views

Pedigree Probability of Autosomal Recessive Trait

Here is a pedigree: The trait is autosomal recessive. The question is: What is the probability that the bottom 2 people (4 and 5) have a child with the trait? I tried doing ...
10
votes
1answer
175 views

Why don't dragonflies wings collapse?

How do dragonflies manage to fly at such high speeds without their wings collapsing? Their wings are thinner than paper, but they do not even flutter. What gives them their strength?
4
votes
2answers
437 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
99 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
2k 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
452 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
90 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
653 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
180 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
371 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. ...
8
votes
1answer
3k 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?
10
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
132 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
3k 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
3k 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?
11
votes
2answers
359 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
223 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?
9
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
814 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
227 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?
7
votes
1answer
133 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
304 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
5k 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
560 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
554 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
197 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
513 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?

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