0
votes
0answers
10 views

Why can´t our dog bark with a high pitch while holding a stick in her mouth? [migrated]

When I throw sticks with our dog (a Swiss shepard) she usually barks at me with a high pitch when I´m about to throw the stick. Sometimes she still has another stick in her mouth and in that case her ...
0
votes
0answers
35 views

What are some explicit examples of natural selection's predominat role in the origin of new species? [closed]

I am taking an evolution course and I found examples in textbook that include examples of organisms that came into form long, long time ago. I could not directly relate their formation to natural ...
2
votes
0answers
126 views

Did I just watch a spider die?

So I'm sitting in my office and all of a sudden a small spider is gliding down on a web string from the ceiling, right in front of my eyes, and down onto my desk. It proceeds to make a few awkward ...
0
votes
0answers
32 views

Are antibiotic-resistant bacteria necessarily less virulent than their original strain?

In the absence of antibiotic treatment, is there a reduction in the average severity of disease caused by resistant strains of pathogenic bacteria compared to wild-type ones? I would assume that ...
3
votes
0answers
28 views

What constitutes FDA's First in Class designation for New Molecular Entities?

What constitutes a First in Class designation for new molecular entities? I've seen this term on FDA documents, as well as in databases (Chembl for example), but I was curious if there are any set ...
0
votes
2answers
479 views

What is Meriva Phytosome Curcumin?

What is Meriva Phytosome Curcumin other than being a food supplement? Is it a plant? A type of plant extract? I googled it but still couldn't figure out exactly what it is. The reason I'm asking is ...
1
vote
2answers
536 views

Calcium for Humans: Supplements vs Fortified Sources

I am intolerant to meat and milk products, but purely natural foods don't contain enough calcium for the Recommended Daily Intake. Links 2 to 4 (but NOT 1) avouch a correlation between calcium ...
0
votes
1answer
21 views

Can cell division be stopped during prophase?

There are three known checkpoints which ensure proper division of the cell. These are: the G1 checkpoint, also known as the restriction or start checkpoint or (Major Checkpoint); the G2/M ...
0
votes
1answer
61 views

Maintenance of Diploid chromosome number at mitosis

I'm just not understanding this: A regular human cell is diploid - because it has 46 chromosomes, in 23 pairs. So that means that when the cell undergoes mitosis, it will still have the full ...
0
votes
1answer
33 views

How diverse are species in remote, isolated areas on Earth? [closed]

If we consider land areas that have been largely isolated from each other from a human point of view, but with a similar climate – for example, a part of Europe and a part of Americas with a similar ...
0
votes
0answers
24 views

What are the chances that a hemophiliac male and an unaffected, non-carrier female could have a baby that is a hemophiliac male? [closed]

The hemophilia gene is located in the X chromosome, which male babies get there X chromosome from their mothers. So the chances of this male baby being hemophiliac is zero. Correct?
-1
votes
2answers
51 views

Wouldn't it be more efficient to let the kidneys flow into the intestines?

So I was thinking about how much fluids we lose when we pee. Then I realised that it would be much more efficient to remove the bladder and let it flow into the intestines so that the fluids can be ...
-1
votes
0answers
32 views

Does washing salad *really* remove E-coli? [migrated]

I don't generally wash salad unless it looks dirty. It's not that I'm unaware of E-coli and pesticides etc, it's that I don't have any conviction that rinsing them with water will significantly remove ...
0
votes
1answer
64 views

Evolution to store limited Fat

Why are our bodies not evolved to store only limited amounts of fat, which won't kill us with all diseases associated with obesity? Wouldn't obese people die faster and clean the gene pool for people ...
0
votes
2answers
52 views

Why does meiotic recombination disrupt the independent assortment of genes on the same chromosome?

There are many sources that say that genes that are "linked" by being on the same chromosome assort with each other -- that when an allele is passed on that the gamete containing said allele will also ...
1
vote
1answer
30 views

What factors make a sequence evolve non-randomly?

On the wikipedia page about Fay and Wu's H, it talks about a non-randomly evolving sequence may be due to some selection acting or a selective sweep or population expanding/contracting. My questions ...
4
votes
1answer
15 views

How do centrioles auto-locate to opposite sides of cell during mitosis?

I realize that centrioles are made of 9 triplets of microtubulin wound together with a hollow core, and that they are responsible for the configuration of the spindle during mitosis. The spindle ...
5
votes
1answer
57 views

Do animals' facial expressions have similar meanings to humans'?

In the following pictures, the dog seems to be smiling to the camera. People staring at these picture also tend to feel comfortable and relaxed, presumably because they think it's very happy playing ...
0
votes
2answers
41 views

Genes that exist in old Affymetrix platform but not in the newer one

I am using two gene expression datasets from an Affy U95Av2 platform and an Affy U133 Plus 2.0 platform. When I map the Affy probe names to HUGO gene names, there are thousands of genes which exist in ...
5
votes
2answers
3k views

Are there human cells, apart from red blood cells and platelets, without a nucleus?

I know that blood platelets and erythrocytes do not have a nucleus. Are there more cells in the human body without a nucleus, such as pancreas, cartilage, or lung cells?
0
votes
1answer
33 views

How does stimulus reach neural threshold?

I understand that when the stimulus into a neuron is greater than the threshold it triggers the action potential. Do all the contributing stimulus have to occur at the same time, or can they occur ...
-1
votes
0answers
14 views

No.of codons at A-site [closed]

If a protein consist of 20 Amino acids. The number of codons exposed at A-site of ribosomes will be: A) 20 C) 21 C) 22 D) 19
0
votes
0answers
27 views

What is the name of the method used for solving the problem?

Problem: A Drosphila sp. heterozygous female of the X-linked recessive traits encoded by alleles a,b and c is crossed with a male that is phenotypically a,b and c. If offprings occur in the ...
2
votes
1answer
57 views

What contributes to the variation of protein sequence across different species?

What contribute to the variation of protein sequence across different species (e.g. phenotype, environment, evolutionary pressure) and how do those factors contribute to the variation? I have tried ...
-3
votes
1answer
24 views

Is volume preserved in the usual photosynthesis reaction equation? [on hold]

Is volume preserved in the usual photosynthesis reaction equation? 6CO2 + 6H20 --> C6H12O6 + 6O2 When I compute volume of LHS, I get 2.21 x 10^-19 cm^3 ...
0
votes
1answer
14 views

What is DNA-cellulose chromatography?

I am going through a paper where they have done DNA-cellulose chromatography to study the interaction between protein and DNA. They are adding the protein to the column and eluting with high salt ...
0
votes
0answers
22 views

Does too much salt in wound cause problems? [closed]

OK, everyone has the experience of eating too much salt and getting a slight headache. But assuming somebody's injured and his wound (you can assume however large you want the wound to be) is soaked ...
3
votes
0answers
85 views

Is a single cell “irreducibly complex”?

(sorry if the title seems like flame-bait - but it's a real question). I'm trying to understand what could have come before the first cell (What are the "minimum requirements" for a single ...
1
vote
1answer
64 views

Symmetry in animals [duplicate]

Is symmetry in animals due to DNA or natural selection? By symmetry, I mean the left side is an almost (not perfect) reflection of the right half. Is this due to DNA trying to balance the two half or ...
0
votes
1answer
41 views

Find the concentration of free receptors in a solution of 90% free ligand and 10% receptor-ligand complex, knowing only the value of kD

I could use some guidance on how to utilise the equation for the disassociation constant kD to find the concentration of free receptors [R] in a solution containing 90% free ligand [L], and 10% bound [...
3
votes
0answers
44 views

Tree ID request

We have a small tree (more like a shrub) in our village of north eastern anatolia, and it is known for its local name which is not Turkish. Even worse I don't know which language it is, but most ...
0
votes
0answers
23 views

What Journals include raw experimental data in publication [migrated]

I was reading an article from Nature Immunology and found that the journal actually includes all the raw data for each figure. I found such practice very helpful, since we can re-analyze the raw data ...
1
vote
1answer
245 views

sodium chloride and amylase activity

So, I did an experiment on the effect of sodium chloride on amylase. and I found out the higher the concentration, the slower the activity. Therefore, is it valid to make the assumption that when we ...
1
vote
0answers
31 views

What is the percentage of true bugs compared to all animal species on the plant?

Also, what is the percentage of True Bugs compared to the insect population? I’m writing a children’s book on bugs and I’m comparing the true bug to the insect. All population info seems to combine ...
0
votes
1answer
29 views

Distance to source populations and/or environmental gradients?

How do you disentangle the effects of distance to source populations and environmental gradients when the environmental gradient occurs in the same direction as the source population? For example, ...
2
votes
2answers
206 views

Coalescence time: Is it different for haploids and diploids in population genetics?

I'm trying to model Cyanobacteria cells divergence in 2 populations with mutation rate $-\mu$ and I need to verify my model with a valid theory. I don't have much biology background and all the ...
1
vote
0answers
19 views

Is blunt end repair and A-tailing necessary when adaptors can be custom made?

I'm planning on creating a RADseq library, which naturally involves digesting genomic DNA following P1 adaptor ligation. I've read a few protocols that require any over-hangs resulting from ...
0
votes
0answers
21 views

Non-malignant cells can still be cancerous?

Say that I am classifying melanoma tumor cells and want to determine of this population which are malignant and which aren't. From a genetic and transcriptional perspective, I could characterize these ...
4
votes
2answers
117 views

Why don't antibodies generally bind to food and drugs?

Are these excluded thru central tolerance? What if you ingested something with a unique molecular structure that you hadn't ingested before?
0
votes
0answers
17 views

Co-dependency between carbohydrates, fats and protein in the mammalian diet?

Following up from the question Are carbohydrates an essential component of human diet? I am interested in knowing more specifically how carbohydrates, fats and proteins are linked in the mammalian ...
0
votes
0answers
13 views

Dosage Compensation? [on hold]

Why is there dosage compensation if you can have the Law of Dominance that can come into play? And if a chromosome is inactivated, then shouldn't people with chromosomal abnormalities be normal? ...
0
votes
0answers
32 views

anabolism in plants

The question is as following: Which substance has the greatest contribution to the anabolism of glucose in plants. A- Oxygen (O2). B- Water (H2O). C- carbon dioxide (CO2). The official answer given ...
1
vote
1answer
38 views

Can salt-water frogs survive in normal water (A well)?

I don't know much about frogs, but there seem to be salt water frogs. 1) Are there such things as salt water frogs? 2) Are there frogs that live in the sea? (in reference to Vivekananda's quote) 3) ...
7
votes
1answer
109 views

Synthesis of Fatty Acids Longer than 16 Carbons

I understand that the human body when performing Fatty Acid Synthesis can synthesize only until C16 (palmitate). However the ER has desaturases and elongases. I know that desaturases are used to add ...
6
votes
2answers
73 views

RNA processing in eukaryotes

Why does post-transcriptional processing of eukaryotic mRNA involve addition of a 3' polyA tail, rather than one of polyU, -G, or -C?
5
votes
1answer
28 views

What happened to the gypsy moth epidemics in the Northeast US?

I remember that back in the 1980s, 1980-1984, gypsy moths were a veritable plague in the Northeast United States. They were literally everywhere. Sidewalks were covered with their squashed bodies (of ...
1
vote
0answers
17 views

Were Neandertals as Hairy as We Are?

What I mean to say regards facial and androgenic hairs. There are many theories as to why some people have both kinds of hairs, while others have one or the same and others still have neither. The ...
6
votes
1answer
98 views

Can microdialysis be made in Drosophila melanogaster?

I've asked this before in stack overflow's cognitive science community, and someone recommended me to ask here: I've found a couple of studies using microdialysis on insects, but didn't found any in ...
0
votes
2answers
45 views

How did scientists establish the reactions that occur in metabolism? [closed]

How did scientists establish that macromolecules like proteins, carbohydrates and lipids are synthesized from other molecules with intermediate products by living cells. Did they observe this under ...
1
vote
0answers
48 views

If the liver can regenerate why can alcohol abuse permanently damage it?

The liver is a fairly unique organ in that it has the ability to regenerate itself even if parts of it are removed/damaged. It is a well known fact that continual alcohol abuse damages the liver and ...

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