1
vote
1answer
131 views

In the context of twin studies, what do 'unique environmental factors' and 'shared environmental factors' refer to?

I was reading this study on sexual behavior and they refer to both terms without clarification. Does 'unique environmental factors' refer only to the prenatal environment or does it include individual ...
3
votes
2answers
785 views

Why does the body not recycle red blood cells?

This question is out of curiosity. The life expectancy of a red blood cell (RBC) is approximately 3 months, and then RBCs are disposed of. Why does the body opt to build new red blood cells rather ...
4
votes
1answer
170 views

Who would win in a fight: an amoeba or a leukocyte?

(sorry, I couldn't resist the rhyming, silly title) I find it facinating that humans can suffer from an amoeba infestation. Amoeba must reproduce far more slowly than bacteria. In size, they seem to ...
1
vote
3answers
87 views

Are there “multi-frequency” signals within a human brain?

I know that neurons can exhibit tonic and phasic firing, and also that a neuron is sometimes called an integrator. This makes me interested to know if there are activities in the brain that depend on ...
5
votes
2answers
127 views

Is there theory that connects longevity, time-scale of environmental disturbance, and adaptation?

I'm thinking here about environmental disturbance or like climate change-driven warming. It seems as if there are two macroevolutionary ways to deal with environmental change: 1) Have short ...
1
vote
1answer
216 views

How to obtain bacteria samples?

Would anyone know how to go about obtaining samples of Salmonella or E. coli for purely educational purposes? Note: I just want to look at the stuff under a microscope.
4
votes
3answers
612 views

Identification of an Insect (Hemiptera)

I found a a few of these guys on my composter, so they could have easily been eating bugs or decaying organics (or both): To me it looks like a stink bug with oversized legs, not like the ones I'm ...
10
votes
3answers
11k views

Do apes and humans share 99% of DNA or 99% of genes? What is the difference?

I made an answer on the Scifi.SE that can be read here. It is about how the characters in the story Jurassic Park might have gotten DNA for all the species shown. In my answer, I said this: Apes ...
8
votes
2answers
5k views

Reasons why people say that AIDS/HIV doesn't exist

It's been recurrent when I hear people saying that AIDS doesn't exist. When I ask why, they give weird reasons like HIV is a virus created to control economy and to develop medicine, etc. Also when I ...
1
vote
2answers
249 views

Does evolution destroy functional sequences much faster than it creates them in any large-genome animal with low reproductive rates?

Recently I have found myself in a discussion with a guy that isn't a creationist, but denies evolution. He cites several studies that show problems like this one, but I do not have the knowledge to ...
3
votes
0answers
68 views

Iron metabolism in the brain

I did an expression profiling from publicly available RNAseq data for mouse tissues. While for liver and testes I am getting expected proteins in the top highly expressed mRNAs, for brain I am getting ...
2
votes
1answer
852 views

Valves in the heart

I am confused regarding the presence of valves in the superior vena cava. The superior vena cava does not possess valves unlike inferior vena cava, which possesses Eustachian Valve. Then where are ...
2
votes
1answer
92 views

Should I design a primer to detect virus based on NCBI genebank?

When I searched HIV on NCBI gene bank, I found 2 results from 1997: http://www.ncbi.nlm.nih.gov/genome/?term=HIV. HIV can change every day, so I think the sequence from 1997 is not useful. Is it?
2
votes
4answers
1k views

Antigen Antibody reactions during blood donation

A person wih blood group O is called a Universal Donor. Well, his plasma contains antibodies A and B. During blood donation, if blood group O is given to a person with blood group A (since blood group ...
1
vote
1answer
88 views

Do non-green flower colors have any functional interactions with the sun?

I always hear the pseudo-evolutionary claim "plants are green because they need to use red and blue light". If this premise to my question is true, What (if any) other functional relationship occur ...
2
votes
2answers
221 views

Realtime PCR plate cleaning

Have anyone used realtime PCR, is that the plate for realtime PCR is one-time using or not ? Otherwise how to clean the plate after reaction to prevent wrong result in next time using ?
1
vote
1answer
19 views

Preventing Diabetes by preventing stress?

I have came to know that taking a lot of stress increases the risk of Diabetes, and patients of Diabetes are adviced not to take too much stress, am i correct? if yes then I am unable to understand ...
2
votes
1answer
586 views

What species is this large-ish spider?

Last night I came across this spider outside my house (costal Southern California). It was bigger than any I'd seen before, about 2.5 or maybe 3 inch legspan, maybe just under an inch for the body ...
6
votes
1answer
525 views

What is this beetle and what are the strange antennae for?

I found this wonderful creature in my yard (I live in the south of France) last night: It was about 2-3cm long, with a hard carapace and wings. It also made loud hissing noises when agitated. I ...
2
votes
0answers
23 views

Living organisms with properties similar to both plants and animals? [duplicate]

Is there any example of currently living organisms that shows close resemblance to both being a plant and an animal? What is the plant with the closest possible resemblance to animals, and What is ...
1
vote
1answer
83 views

Can ant colonies have two “branches”?

Could an ant colony have 2 or more "branches" located far from each other (i.e. physically separated but interconnected nests) ? If so, how far is the limit?
5
votes
1answer
189 views

Improving transformation efficiencies- induce supercoiling?

From my limited knowledge of science, I know transformation can be one of the hardest step in cloning, and that a large amount of research/trial and error has been done to improve on this step. I've ...
3
votes
2answers
88 views

How does the DNA know which chain has error in repairing?

As we know, the DNA has more stability than RNA, if one chain has broken or accidentally distorted, it can be repaired by the other one. Suppose there is a segment AGTC, its peer is GACT. Now its ...
0
votes
4answers
2k views

Are chromosomes from each parent split between gametes with equal probability (esp. in humans)?

I've recently read a little on Wikipedia about genetics, but I can't find a direct answer to this question. My rough understanding is this: Both males and females have pairs of chromosomes, one ...
1
vote
1answer
136 views

DNA Replication

I just wanted to understand the basic steps behind the replication of the lagging strand of DNA: Have helicase unwind it first DNA Primase lays down RNA primers in fragments, called Okazaki ...
1
vote
1answer
41 views

Can antimicrobial peptides be called antibiotics?

Antibiotic peptides are present in almost all multicellular eukaryotes. So can they be called antibiotics ? ( which are usually defined only for fungi and bacteria )
2
votes
2answers
97 views

What causes autism?

What causes autism? By this I don't mean what is to blame i.e. Vaccines, Gluten or Pharmaceuticals etc.. I mean what exactly is happening in the brain to cause the autistic behaviors such as little ...
3
votes
0answers
126 views

Good poly-A filtering rules or tools

I am aligning a large number of ESTs. It seems poly-A tails show in many different ways. In addition to occurring at the very end, they can be flanked by the cloning sequence one one end, or have ...
7
votes
4answers
553 views

Suitable introductory book on Bioinformatics for a computer scientist?

Do you have any suggestions on a suitable introductory text on bioinformatics for a computer scientist? Any recommendations with pros and cons of different books would be appreciated. I'm mainly ...
7
votes
1answer
151 views

What is the limit of time resolution in fMRI?

I was reading about a few studies on estimating functional connectivity between brain areas using fMRI signals. However, as far as I know that fMRI has a very poor time resolution, roughly in the ...
3
votes
1answer
175 views

Hearing and neurons- do ears have a sampling period?

From what I have read, outer hair cells in the human ear amplify incoming signals and inner hair cells "pick-up" the signals and generate action potential. However, neurons have refractory periods ...
4
votes
1answer
2k views

Does photosynthesis require only direct sunlight

I have learned throughout my basic science classes in high school that in the process of photosynthesis, plants absorb sunlight & produce food. They use carbon dioxide & water vapour. My ...
6
votes
3answers
448 views

Mitochondrial DNA and recombination

Firstly I could do with a brief description of mitochondrial DNA. How does the structure of DNA in mitochondria compare to animal DNA (for the sake of simplicity let's say human - some animals might ...
5
votes
1answer
207 views

Do thymine and uracil ever appear in the same strand of RNA?

Wikipedia says that "in RNA, thymine is replaced with uracil in most cases." I'm curious what are the cases when this does not happen? Does this ever occur in normal functioning, or is it an error? ...
2
votes
1answer
1k views

Difference between Bioscience and Lifescience

Are bioscience and lifescience the same things? I am a little bit confused about it. If not, then what is the difference between the two?
2
votes
1answer
179 views

DIY extraction and long term storage of human DNA sample?

What is the recommended DIY way of extracting and long term storing of human DNA samples to store at home and send for sequencing in years time? Considerations: Sample material: cheek swab, hair, ...
6
votes
4answers
463 views

What is the viability of Intelligent Design as a supplement to chemical abiogenesis and Darwinian Evolution?

First of all I am not endorsing Intelligent Design (Wikipedia link); I'm asking this because I (someone who does not have a background in biology, organic chemistry, or philosophy) got into a ...
1
vote
1answer
187 views

Can PolyA tails be within Expressed Sequence Tags?

Can polyA tails occur within (rather than at the end) of a sequenced tag? Consider, for example the following two sequences from NCBI: DY008075 ...
0
votes
1answer
67 views

Some question about materials for PCR

I'm planning to order oligo, polymerase, nucleotide, buffer for my first diy PCR experiment (now I have nothing), so I have some questions. How and how long I can storage them? I have only a fridge ...
7
votes
3answers
3k views

Why do we squint when tasting very sour things?

Sometimes while tasting a very sour thing (like tamarind, lemon etc.) our eyes squint immediately and involuntarily for a second, but a little later becomes normal again. Why, and how, does this ...
1
vote
1answer
382 views

How different is an introverts brain different from an extroverts?

How is an introverts brain wired differently than an extroverts? Just to give you an example. On an average, the processing that goes on in an introverts brain is greater than in an extroverts ...
1
vote
1answer
63 views

Carotenoid biosynthesis in yeast

Does Budding Yeast Sacchromyces cerevisiae produces significant amount of carotenoids? Have anybody estimated the ratio of flux going in branches 1. Cholesterol synthesis(via squalene) 2. Coenzyme Q6 ...
5
votes
2answers
234 views

Can PCR tubes be made of different materials than plastic?

Does it matter if I replace the PCR tube (usually made of plastic) with another material like aluminum, glass, or something similar?
2
votes
2answers
299 views

Can a dNTP be built into a RNA strand?

DNA consists of deoxyribonucleotides, RNA consists of ribonucleotides. They differ mainly (apart from the uracil / thymine difference) in the sugar part, the deoxyribose and the ribose. Those two ...
0
votes
1answer
345 views

Confusion regarding photosynthesis and respiration in plants

During 24 hours there is a time in i.e. twilight when plants neither give oxygen nor carbon dioxide why is it so? This also suggests that neither of the two vital processes i.e. respiration or ...
3
votes
1answer
134 views

Method to recognize the age of a firebug from the pattern on its back

Can I recognize the age of a firebug from the pattern on its back? If yes, what pattern shows what age/stage? Below is what I extrapolated from Wikipedia, but is there a more precise scale with more ...
1
vote
0answers
61 views

Which are the most extreme artificial environments that lifeforms/ecosystems have adapted to?

I have heard of 'extremophiles', lifeforms that naturally thrive in all sorts of extreme environments. Is there any evidence to suggest that lifeforms are adapting to the extreme environments (such ...
1
vote
1answer
49 views

What Effect would Cannabinoids have on the Acute Porphyrias?

I should be clear in saying that this question is NOT intended for personal medical advice. Rather what I am looking for is journal articles and/or books that touch on this subject because I think it ...
4
votes
2answers
862 views

How does ubiquitin recognize misfolded proteins?

Misfolded proteins are tagged by ubiquitin and then are destroyed by proteasomes. How does ubiquitin know which protein to tag?
5
votes
1answer
81 views

Selective Androgen Receptor Agonist

I'm looking for an inducer that strongly activates the androgen receptor, but not the glucocorticoid receptor that is not DEA regulated. I know that SARMS (Selective Androgen Receptor Modulators) are ...

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