1
vote
0answers
89 views

How TCGA CNV values are calculated?

When I download CNV SNP array data for ovarian cancer from TCGA data portal, I see some very small numbers like -5, -6 in the "Segment_Mean" column of the segmentation data files. I am very new to ...
9
votes
1answer
119 views

Circadian Clock During a Flight

I am interested to know how does our Circadian Clock respond (and its resultant changes if any) when we are traveling across Time Zones? UPDATE 24th April I am reopening this question as the ...
3
votes
0answers
36 views

Y Chromosome in Ovary Cancer Data

I have been analyzing TCGA Ovary Cancer data. In Somatic Mutation data, there is data of mutations in all the chromosomes (1-22 and X), but amazingly, I have found one (just one) row of Y Chromosome ...
2
votes
1answer
20 views

Why are 2 electrons transported from photosystem II at the same time?

I only know that electrons are captured by the primary electron acceptor and then go through the electron transport chain, ultimately ending up at photosystem I. But why do 2 leave photosystem II in ...
3
votes
1answer
19 views

Does the palate truly house the sense of taste?

Source: Your “palate” is the roof of your mouth, and by extension, your sense of taste. I was reading Etymonline's entry for palatable {adj.}, which cites and derives from palate {noun}: ... ...
7
votes
2answers
1k views

Is blood an organ according to biology?

It consist approximately 7 percent of body weight. By definition organ is composed of multiple tissues. Blood is a fluid, a circulating tissue. Therefore can we call this fluid system a liquid ...
4
votes
1answer
36 views

What is the difference between intrinsic and extrinsic apoptosis?

Hello my Professor has been teaching about apoptosis and sometimes makes the distinction between extrinsic and intrinsic. I am not sure if I know for sure what this means. Does this just refer to ...
4
votes
1answer
29 views

Are all protein composed of all the amino acid (in animal) or are there less diverse protein?

I have a question about amino acid composition of proteins: Are there proteins in animals that are made up only from a small subset of amino acids? So instead of all 20 amino acids let's say only 6-14 ...
22
votes
3answers
2k views

Hot water and bacteria

I know that it is common to say, "use hot water when washing your hands" or when you've got a cut, "wash your hands with warm water," etc. I was wondering, why is this the case? Since bacteria grow in ...
2
votes
1answer
22 views

Is RNA polymerase affected by proteins bound to the coding sequence of a gene?

I am designing a synthetic gene construct to express genes in E. coli driven by either Ptet or PLacO. The construct would look like: -Ptet-(Gene1)-PLacO-(Gene2)- I want to express each gene using ...
4
votes
1answer
46 views

Do non-enzyme catalysed reaction pathways exist?

Can their be a kind of chemical reaction pathway in a cell, that is catalyzed or regulated but NOT necessarily by enzymes? I could not find anything on Google. I have almost no background in biology, ...
2
votes
1answer
22 views

Is cysteine deficiency possible?

Is there such a thing as cysteine deficiency in humans or other mammals? What effects would such a deficiency have? As I understand it, most cysteine for humans comes from dietary sources, though it ...
4
votes
1answer
33 views

Are stem cell lines also kept worldwide like HeLa cells?

There are HeLa cells, which were taken from sick cancer patient and now is growing worldwide in different laboratories for experiments. HeLa cells can be kept because they are immortal and so they are ...
4
votes
1answer
19 views

In human females one X chromosome is inactivated forming Barr Body. Then How exactly Haemophilia is dominant? check description for details

Suppose a female has one X chromosome normal and one chromosome with Haemophilic gene. Now suppose if the X chromosome which is normal is inactivated will the female show haemophilia?
4
votes
2answers
128 views

Do acetyl-CoA, acetyl-CoA carboxylase and acetyl-glutamate carry any charge?

Do the following compounds have any charge? If not, then why? If yes, is there any database that would give me this information if the compound is negatively or positively charged? The compounds are ...
5
votes
1answer
139 views

Are HeLa cells edible?

I'm curious if HeLa cells are intrinsically poisonous or dangerous to ingest. My understanding is that some of the contamination in HeLa cells such as HPVs are not readily expressed. I have no plans ...
0
votes
0answers
9 views

What light conditions facilitate communication between birds with black and white plumage?

I'm studying two populations of birds: Population A and Population B Population A has a small white patch on its neck. Population B has a large white patch on its neck. See attached diagram. It is ...
8
votes
1answer
61 views

What is the difference between influenza A and B viruses that causes their distinct seasonal patterns?

I recently learned from an answer at health.SE* that influenza B tends to occur later in the season compared to influenza A. According to the graph in that answer, during this year’s flu season the ...
3
votes
1answer
23 views

Mammal vs Placental Mammal

So for Google Earth Day's quiz I ended up being a "Pangolin." Turns out I had no idea what it was so I looked into it and honestly it reminded me a lot of an Armadillo. So I decided to find out the ...
27
votes
4answers
5k views

Why don't mammals have more than 4 limbs?

Arthropods have 6 or more limbs and arthropods with 6 limbs appear to move faster than arthropods with 8 limbs so I wonder whether this might have something to do with fast and efficient locomotion. ...
2
votes
1answer
29 views

Help reading gene markers

I'm sorry if "gene markers" is not the correct word. An edit could be appreciated but I don't study in an English speaking country unfortunately. Question overview: In a family, there is a genetic, ...
5
votes
1answer
38 views

what is linkage disequilibrium supposed to measure?

During reading about genetics I came across with the term of linkage disequilibrium, and I do not really understand what it supposed to mean. What is linkage disequilibrium? My current understanding ...
6
votes
0answers
38 views

What are the survival limitations of alcohol?

This question was inspired by watching one of the Pirates of the Caribbean movies; particularly where Jack Sparrow allegedly survives on a desert island by finding an unlimited supply of rum. I've ...
2
votes
2answers
36 views

Does the biosphere have infinite resources and are they infinitely renewable?

Does biomass represent all of the resources of the biosphere and therefore it would be theoretically infinitely renewable (as long as we have the sun) since all the biomass is part of the carbon ...
3
votes
1answer
44 views

Why do spiders make their web near the ceiling and near a light source?

Why do spiders make their webs near the ceiling and near light sources ? Is their an advantage for spiders in doing that? For example do they catch more insects when their web is near a light source ...
5
votes
1answer
51 views

Do we instinctially interpret birdsongs as a sign that there are no predators present?

I was outside today thinking how nice it was to hear the birds back from winter when I started thinking about the fact that we like bird song. It makes us happy in a very basic level, the sort of ...
2
votes
2answers
31 views

Help reading chromatogram

A genetic variation is found in this chromatogram: It says that the "reference sequence" is the top line and that I can use the general genetic code to find the reading frame. I can see that there ...
4
votes
2answers
29 views

Immediate stroke/seizure Therapy

Can an oncoming stroke/seizure, be stopped by a setup consisting of a brain-computer-interface (BCI) that immediately detects the variation in wave-form, and then another machine that neutralizes the ...
2
votes
1answer
37 views

Why are clementines easier to peel than oranges?

In my experience, clementines have been significantly easier to peel by hand than and orange. The skin of the orange seems to cling to the rest of the orange much more so than the skin of the ...
4
votes
1answer
32 views

blue/white screening - results are opposite as expected

We inserted GFP-gene into plasmid Bluescript SK+, transformed E. coli with this construct, and then plated on an agar plate with Ampicillin and X-gal to do a blue/white screening. We got blue colonies ...
13
votes
1answer
412 views

What is the magnification necessary to see pond life

My daughter is 5 and wants to learn about Biology. I thought a great start is to see life from pond water through a USB microscope. It would be great if she could see organisms like amoebas, ...
4
votes
2answers
57 views

Does DNA polymerase always go the same direction?

I read that mutations are more likely to occur on "the strand that DNA polymerase replicates discontinuously". Does DNA polymerase always go replicate the same strand discontinuously, and if so, ...
2
votes
1answer
31 views

What does it mean when a protein has a different excitation spectra than wildtype, but the same emission spectra?

We have a GFP mutant that displays a different excitation spectra with emission at 510nm than the WT. However, their emission profiles with excitation at 490nm are the same, and we do not observe the ...
6
votes
5answers
1k views

Why don't we breathe nitrogen when it makes most of the air?

Why don't we breathe nitrogen while it makes most of the air? Why do we always tend to breathe oxygen, not hydrogen and nitrogen?
1
vote
1answer
29 views

What are the factors on which protein-protein interaction depend? [closed]

Does protein-protein interaction only happens when one of them is basic and the other acidic? Do protein interactions also depend on the protein structure? Are there more factors?
5
votes
2answers
54 views

GWAS: why is replication in another cohort so crucial?

Almost all the landmark GWAS (Genome-Wide Association Studies) reviews agree that, for a GWAS finding to be valid, it needs to be replicated in an independent cohort. What exactly is the rationale ...
37
votes
3answers
3k views

Why does cracking a joint make noise?

What causes the noise when you crack a joint? Is joint cracking harmful?
8
votes
1answer
633 views

What causes knuckle “popping” and the feeling of relief that comes from it?

Many people like cracking their knuckles. I have always been curious about it. What happens when we crack knuckles? What creates the POP sound? Why do we get a relief-like feeling after doing it?
3
votes
1answer
34 views

Applying kiwis on gelatin

Kiwis have the enzyme actinidain. This enzyme will break the peptide bonds from the gelatin. Making gelatin with raw kiwis will not work, because the peptide bonds in the gelatin will be broken down. ...
4
votes
1answer
82 views

Help me identify this insect

Over the last week or so as warmer weather has arrived, I've noticed small insects crawling around in the bathroom. I'm located in western Europe. They are perhaps 1mm in length, quite difficult to ...
2
votes
1answer
36 views

“bead” on a string theory of genetics, source?

Thomas Hunt Morgan was a pioneer in genetics and proposed the now false model of genes being "beads" on a string. These beads being indivisible and responsible for a single phenotype, if I understand ...
1
vote
0answers
10 views

OCT-1 transport in Enterocytes

Does Oct-1 transport lactate or any of its products and in which direction (intracellularly to extracellular, the opposite, or inter-nuclear). The literature talks about Oct-1's role in neuronal ...
7
votes
1answer
2k views

Why are pili more common in Gram negative bacteria than in Gram positive?

Although pili have been observed in some species of Gram positive bacteria, the preliminary research that I have done indicates that pili are significantly more common in Gram negative bacteria. Is ...
6
votes
1answer
69 views

Is using Hidden Markov Models to find homologues sensible in abstract, short sequences?

HMM alignment tools like hhpred excel at finding subtle homologues of folded proteins that simpler scoring techniques (such those used in BLAST algorithms) would miss. I am only looking at a small ...
4
votes
1answer
30 views

Why do plants produce so many hybrids as a kingdom?

Why do plants produce so many hybrids? I have read that they are the largest kingdom of organisms to do so. Does this have something to do with polyploidy events?
7
votes
1answer
49 views

Magnetic-activated cell sorting vs. FACS

When sorting cell populations it is possible to use either magnetic-activated cell sorting or fluorescence-activated cell-sorting (FACS). I am wondering when you would choose either technique and what ...
4
votes
0answers
58 views

Current Trend in Evolution of Human Intelligence

Up front, I am specifically not interested in philosophical or ethical considerations re Eugenics and related concepts. In an effort to receive a concise answer I'll post a narrowly defined question ...
4
votes
1answer
42 views

Powdered meal replacement vs regular meal

Can a person live with this alternative nutrition? Of course, assuming that eating pleasure is assumed the same. The nutrients that contain are far better than average meal a person eats the majority ...
5
votes
1answer
34 views

Why can I see a light flicker when it's in my peripheral vision?

When I'm looking at an old CRT monitor or a worn fluorescent lamp, but not directly in the center of my gaze, the light from it seems to flicker. When I focus my gaze onto the monitor or lamp, the ...
4
votes
0answers
43 views

Why do we get tired

At the end of a day full of work, it is general for people that their eyelids start to feel heavy. Laziness takes over and we begin to yawn. We all know that we're tired at that time, but why people ...

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