2
votes
1answer
59 views

Expression of bidirectional promoters

How are bidirectional promoters expressed ? (Won't RNA Pol have to go in 3'-5' direction?) Why are they more commonly found in eukaryotes than prokaryotes?
2
votes
1answer
100 views

How can a continuous RNA be transcribed in the lac operon?

The lac operon has 3 genes: lacZ , lacY and lacA. I have seen that the m-RNA transcript of these genes has stop codons in between. So, how can the RNA be made continuously? Won't the RNA Pol detach if ...
4
votes
1answer
99 views

Was life less colorful before color vision evolved?

According to Wikipedia, we know that color-vision photopigments appeared in the common ancestors of tetrapods and fish at least 360 MY ago. Would life have been less colorful before the evolution of ...
0
votes
1answer
288 views

Why does air from the nasal cavity not go into the oesophagus?

When we ingest food, the epiglottis covers the trachea and the uvula covers the nasal passage. But what happens when we breathe? Why does the air go into our trachea and not the oesophagus?
2
votes
2answers
388 views

What can cause incompatible sticky ends to be ligated?

Actual question I have reason to believe (details see below) that in a ligation I carried out, an EcoRI sticky end (EcoRI: G'AATT_C) and an XmaI sticky end (XmaI: C'CCGG_G) were somehow ligated ...
2
votes
1answer
32 views

Material on the analysis of (micro)array data

I'm at the moment analyzing cytokine array data. The available material on the statistical analysis of these data is more than unsatisfactory. Since a lot of effort is being made in the analysis of ...
1
vote
1answer
741 views

Why do I always close my eyes when someone takes a photo of me using a flash?

Everytime some tries to take a photo of me with a flash I manage to close my eyes (blink). It's not intentional and it's quite annoying. Why am I doing it?
1
vote
1answer
106 views

Why are some fungi poisonous?

There are many poisonous fungi in nature. For example Amanita Phalloides. What reasons could a fungus need poison for? Some species, like venomous snakes, use poison to kill other species as prey. ...
1
vote
1answer
96 views

Can viruses protect themselves against restriction enzymes?

Restriction enzymes cut the DNA of bacteriophages. Have bacteriophages evolved any mechanism to protect themselves from it ?
6
votes
3answers
148 views

Why are diabetic people often overweight?

I was looking at diabetes the other day, and I noticed something strange. Lower amounts of lipase are a symptom of diabetes, as is overweightness. However, since lipase is the enzyme that breaks down ...
2
votes
1answer
61 views

Bioluminescence and photovoltaics

I work in the PV industry and was asked a question recently during a presentation. Could Bioluminescence provide enough light to power a PV array during off peak hours? I understand the PV portion and ...
3
votes
1answer
67 views

What happens if we continuously stimulate a mimosa plant?

I know there is some mechanism in humans by which we start to ignore a certain stimuli if it persists for a long time (e.g., we don't feel our shoes all the time !). Can the same thing happen in ...
1
vote
0answers
1k views

What are potential side effects of myostatin inhibitors?

Myostatin inhibitors, which are being developed to treat muscle wasting diseases like muscular dystrophy, are likely to be abused by athletes. What are the potential long-term side-effects of taking a ...
6
votes
1answer
805 views

How do lilies sense day and night and open and close their flowers?

We have lots of lily flowers inside our garden. Their flowers are open in day and closed in night. How do lilies sense day and night and open and close their flowers?
3
votes
1answer
723 views

Neuromediator, Neuromodulator, Neurotransmitter?

Of these three words, perhaps Neurotransmitter is the most obvious. I took a look at Wikipedia page for Neuromodulation and found that this is pretty similar to Neurotransmitter too. I guess ...
1
vote
0answers
53 views

Is there a realtime molecular clock within the genome to co-ordinate the developmental sequences in an embryo?

It is difficult to assume that the massive number of co-ordinated developmental sequences in a developing embryo is controlled by molecular signalling alone. Is anyone aware of a molecular or ...
4
votes
2answers
131 views

Plant identification?

Can anyone identify the plant below? It's in a backyard in Pennsylvania, and the photo was taken today.
2
votes
3answers
371 views

Are there any scientifically based predictions or theories of future human evolution?

Reading this question of the stack exchange got me thinking. I believe human evolution is an ongoing process and will not stop. Are there any predictions/theories about the phenotypes and genotypes of ...
3
votes
1answer
320 views

Do hormones make men think of sex?

I remember hearing a saying that goes like "men think of sex every 7 minutes (or seconds?)". I take this saying to mean that men have sex related thoughts more often than women. I'm interested if ...
-2
votes
1answer
61 views

How do I figure out which of the valleys I came from?

I had my DNA tested by 23andme.com. They give me a very long string for my DNA. How do I determine which of the three Ethiopian valleys I descended from? I'm of European descent. ...
3
votes
1answer
5k views

What is the standard deviation of adult human heights within sexes?

The wikipedia article on human height reports mean height for many different countries by sex but it does not report standard deviations. What is the standard deviation of adult human heights within ...
1
vote
0answers
23 views

Is there a database of pollen-seed distances across plant species?

I was enjoying Richard Smith's excellent answer to this question, and wondered: If you consider the pollen/seed distribution range to be plant locomotion, is there a database that compares these ...
5
votes
2answers
151 views

What are common causes of unexpected ligation products?

I digested two plasmids, one with EcoRI and AgeI and the other with EcoRI and XmaI. Digests looked as expected, so I purified the respective fragments and set up the T4 DNA ligation (AgeI and XmaI ...
4
votes
0answers
42 views

Honeybee decision process: new food, new home, new threat

I have heard that honeybees send out scouts, then based on the scout reports more bees go then come back and report and so they are supposed to be efficient decision makers. Can you give as complete ...
2
votes
1answer
33 views

Why are dreams sometimes remembered and sometimes forgotten?

Why is it that sometimes, when we wake up, we are able to remember what we were just dreaming, but sometimes we don't remember any of it?
5
votes
0answers
231 views

Reason for seeing grid-like patterns when strobing a solid black-white image?

I was trying to do some stimulation for SSVEPs by strobing a solid black square and a solid white square. Weird thing was, I ended up seeing weird grid like patterns that looked like this, always of ...
2
votes
1answer
74 views

Can plants survive indefinitely without external supply of gases at compensation point?

During photosynthesis, there is a point at which the light intensity is such that the rate of photosynthesis exactly matches the rate of respiration called the compensation point. What this means is ...
6
votes
1answer
283 views

Why do people sleep with their eyes open?

It's a fact that some people sleep with their eyes open, but why does that happen? Is it normal behavior, not a symptom of any sort of disorder? Are there any (dis)advantages to sleeping with eyes ...
6
votes
2answers
563 views

Do animals get sick from eating dirty food or eating off the floor?

Humans have very strict tradition of hygiene, such as washing hands before eating, using utensils, and in general keeping as much distance between food and dirt as possible. At the same time, most ...
2
votes
1answer
74 views

What's the difference between Cytoplasmic pool and Granular storage pool?

What's the difference between Cytoplasmic pool and Granular storage pool when speaking about neurotransmitters and synaptic cleft. I encountered this here: Amphetamine’s mechanism of action thus ...
3
votes
1answer
74 views

What causes sinus pain and congestion?

When the sinuses flare up, it can get very painful. Thus, my question - what biological mechanisms cause the congestion and especially the pain associated with sinusitis?
2
votes
1answer
58 views

Why is duck fat less saturated than cow fat?

Why does the composition of fat in animals vary? Is there an evolutionary advantage to producing fat that is less or more saturated?
0
votes
1answer
21 views

Known MicroRNA - Gene Systems?

Have there been any experimentally-verified systems of microRNAs targeting a gene set (e.g., in cancer, perhaps)?
2
votes
1answer
66 views

Do insects respond to the detection of dead insects?

Are there insects that change their behavior upon detecting the nearby presence of other dead insects? If there are, can you provide an example?
3
votes
1answer
182 views

Why does the stomach ache if you take a brisk walk after lunch or dinner

After eating your lunch or dinner, if you take a brisk walk, most of the time your stomach aches. Why does that happen? What happens with respect to the body metabolism?
2
votes
2answers
1k views

What is genomic imprinting?

What is a genomic imprint? How does genomic imprinting take place? If I say that "this" allele is maternally imprinted does it mean that the allele of the gene is passed only by the mother? If a ...
2
votes
1answer
44 views

Determination of gene direction

I have one sequence that composed of sequences of three genes. I should determine the direction of each gene, but two of these genes are disrupted, and I can't determine the initial codon. Does anyone ...
5
votes
2answers
88 views

Are SLC52A2 and GPR172A really the same?

The official HUGO gene nomenclature page says that GPR172A (Gamma-hydroxybutyrate receptor) and SLC52A2 (riboflavin transporter, member 2) are the same. The sequence reported by Andriamampandry seems ...
2
votes
1answer
51 views

Use of pigs for obtaining transplant organs

It is being said that organs can be obtained for transplant from the pigs. What is special about pigs that we are using them? Why can't we use monkeys or chimpanzees with whom we share a more recent ...
2
votes
1answer
58 views

What decides the position of the node of Ranvier?

The oligodendrocytes makes the myelin sheath in CNS and schwann cells make it in PNS. What decides where the oligodendrocyte or Schwann cell will attach and start forming myelin sheath? Is it ...
3
votes
2answers
277 views

How can sex ratios remain Fisherian (1:1) in species where only the dominant male gets to mate

In certain species only the dominant male gets to mate (or given strong preference), and yet the sex ratio remains 1:1. (I'm thinking in particular of gorillas). How does this happen? It doesn't seem ...
2
votes
1answer
479 views

Difference between viral and human genetic material

I have heard that there is a difference between viral and human genetic material. What is that difference? If I take my cells and take DNA out of them and insert only a small part of it having a ...
2
votes
2answers
157 views

Why did Fair Meiosis evolve?

How and why did Fair Meiosis evolve? I can hardly think that it provided a fitness advantage to the individual carrying the mutation. Why would it? Or did it evolve through lineage selection? Or was ...
4
votes
1answer
75 views

Randomness in living systems

The point of my question is not to talk about events that are uncontrolled by living organisms. My question is about controlled randomness, or I'd like to say adaptive random process. Process that are ...
7
votes
2answers
2k views

Can one die from pain?

Is it possible that a human or any other creature can die from pain? I googled and found different answers. Some articles say Yes while others say No.
2
votes
1answer
99 views

What areas of the brain are involved in doing arithmetic operations?

Do neuroscientists already know what areas of the brain are involved in mental calculations? Has any fruitful research been done on that or not yet? Do you think that if we understand what areas of ...
1
vote
0answers
100 views

Green feather-like formations in tap water - what is it? (with pictures)

These things recently appeared in my tap water Copenhagen Denmark, this summer 2013. They are very small, and have a feather like structure. I've called the water supply, and they thought that it was ...
1
vote
1answer
144 views

If people with colorblindness lack one type of cone cells, shouldn't they be unable to recognize one particular color?

The 3 types of cone cells in normal humans allow them to view 3 types of colors and any color made from mixing and matching those 3. So, 2 types of cone cells should only allow to view just 2 types ...
2
votes
2answers
107 views

Do people with colorblindness have less cones or no cones of a certain type?

https://en.wikipedia.org/wiki/Color_blindness#Red.E2.80.93green_color_blindness Protanopia (1% of males): Lacking the long-wavelength sensitive retinal cones, Deuteranopia (1% of males): ...
1
vote
1answer
100 views

Molecules and human memory

Has it been demonstrated that the memory of human brain is just connections between neurons, not "long" molecules such as RNA or proteins?

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