1
vote
1answer
30 views

Consequence of touching Formaldehyde

I accidently touched formaldehyde some days ago. Skin on my hand got dehydrated as if I had placed it in salt solution. I washed it with water and it returned to normal state after 5 minutes. But now ...
1
vote
1answer
21 views

Concentration of DNA by isopropanol

I have read that DNA can be concentrated by addition of isopropanol. What does "concentrated" mean? What does isopropanol do on a molecular level to concentrate DNA?
1
vote
2answers
37 views

Functioning of EDTA

I know that EDTA chelates metal ions. It weakens bacterial cell wall and inactivates the DNases. What is the reason why it can do so ? I guess it can inactivate DNases by altering the ...
2
votes
1answer
42 views

Why does ear wax taste sour?

Why does ear wax taste sour? I am interested in both the physiochemical mechanisms and the evolutionary reasons behind the sour taste of earwax.
1
vote
3answers
42 views

What problems do invasive species cause ?

Why do we value species? What is so bad about invasive species? Why value biodiversity?
0
votes
1answer
42 views

Do chicks in eggs excrete?

I want to know if, as a baby chick grows inside the egg, does it excrete waste? If it does excrete waste, does the waste just sit inside the egg with the chick, until the chick cracks open the egg ...
1
vote
1answer
29 views

What happens when we dream?

When a human dreams does the brain activate the cones and rods in the eyes creating the images we see in dreams?
2
votes
1answer
16 views

How do B memory cells provide immunological memory? Do they differentiate into plasma cells?

My text book doesn't say anything about how B memory cells actually ensure a faster response the second time the antigen is encountered. My guess is that they differentiate into plasma cells which ...
0
votes
1answer
22 views

Fertilization of an egg by two sperm

What happens when two sperm fertilize an egg? This can be either naturally or by experiment.
1
vote
1answer
24 views

Mutated Sperm - What happens?

I saw on TV that not all sperm are the same. Some have mutations like 2 and 3 tails? There were other mutations as well. If one of these mutated sperm actually fertilized an egg, would the embryo ...
1
vote
1answer
16 views

Affect of the health of the male parent at the time of conceiving

Does it matter at all in determining the traits of a baby what the current health of the father is? For example, let's say I got diabetes at the age of 40 because of the poor lifestyle choices. Will ...
1
vote
1answer
38 views

What is the current theory of sexual orientations in Biology?

What is the current explanation of what causes the different sexual orientations in humans.
12
votes
4answers
2k views

Do any organisms recycle their own waste internally?

I thought of this question yesterday and it turns out it's surprisingly hard to Google.
2
votes
0answers
18 views

Does apheresis damage any components of blood? If not, why not?

Blood donation involving apheresis is becoming increasingly common. It looks like the process involves centrifuging blood at very high speeds* before removing the desired fraction and returning the ...
0
votes
0answers
19 views

Antimicrobial Compounds in Common Plants?

Are there any common plants that contain compounds with anti-microbial effects? I tried googling the answer, but got bogged down in bio-jargon abstracts. What I'm really looking for is some plant that ...
1
vote
1answer
41 views

Buy bacteria for experiment?

Where can I buy paracoccus denitrificans? I need it for an experiment. I cannot find online where I can purchase this.
2
votes
0answers
43 views

A day in Beijing is like smoking Only one sixth of a cigarette

This is the title of this blog post followed by this other good post. I'm particularly anti-tobacco-smoke, at the point of not always considering other pollution, and this article shows how this kind ...
2
votes
2answers
46 views

Evolution of bee hives

How do the instinct to create a hive appeared in bees? Is there some evidence of "intermediate" hives? With this questions i mean all the factors necessary to build a hive, including the social ...
0
votes
2answers
47 views

DNA adaptation in human life

Does our DNA adapt by human lifetime? Or do we have the same genetic information from birth to death? I mean: What is usually called "evolution" means "natural selection" like this: ...
2
votes
1answer
35 views

Structure of biological membranes?

Integral membrane proteins have functional asymmetry i.e. they have two different domains of proteins performing different functions. these proteins have Tyr and Trp amino acid residues at the ...
0
votes
0answers
23 views

Spinal cord injury bypass

When the spinal cord is damaged, the connection between the brain and some part of the body may be lost. To restore this connection, some research are carried out, with mainly two different goals : ...
0
votes
0answers
20 views

Clustal Omega - convert from distance into # of substitutions

I have a set of nucleotide sequences for which I have aligned using Clustal Omega. In particular, I performed a full alignment, and obtained a full distance matrix. The distance matrix scores range ...
1
vote
2answers
50 views

Epithelial cells and Rhinovirus

If you injected a tumor with epithelial cells infected with the Rhinovirus, would this still evoke an immune response as it would with the respiratory system? Secondly, what is the specific reason the ...
3
votes
0answers
21 views

Are there specific features of birds that cats/small predators are attracted to?

I've recently heard a podcast, in which a professor describes one of the theories as to why we like abstract art. In his talk, he mentions an experiment with seagull chicks, in which the seagull ...
4
votes
1answer
235 views

How can highly virulent but uncommon diseases (like ebola) maintain a stable equilibrium?

I'm wondering how can very uncommon diseases remain in a relatively stable equilibrium. For example, if it started to spread, the spread could accelerate and become an epidemic. However, if it doesn't ...
0
votes
1answer
48 views

Are females more flexible than males in all mammals?

It's common that human females have a more flexible body than males, (but I don't know why, so it'd be helpful if someone answers why so as well!) but does this apply to all mammals?
1
vote
2answers
81 views

Real time PCR standard curve

As blunt as possible: when performing real time PCR it is a routine step to run one PCR in order to plot a "standard curve" with several decreasing dilution ratios from your sample. what is the real ...
0
votes
0answers
18 views

In what forms do plants and animals excrete sulfur?

Sulfur is part of the amino acids cystein and methionin, plants take up sulfur in the form of $H_2S$. These organisms will also need a way to get rid of excess sulfur, how? In what compounds? Judging ...
5
votes
1answer
75 views

What causes Paresthesia (Pins and Needles) at a cellular level?

I've looked it up in plenty of places like the Wikipedia page and such, and it is clear that the most common cause of Paresthesia is either a fair amount of pressure on a specific patch of skin ...
1
vote
2answers
25 views

Is there any bank of animations for Embryology?

I am trying to find animations which can anonymous or generalised for Embryology. However, I have not find any single good source. Is there any bank of animations for generalised embryos?
0
votes
0answers
10 views

How does vasomotor and bronchomotor reactions equilibrate local blood flow to correspond local ventilation?

I am trying to find some figure(s) to explain this. There is probably better name for "bronchomotor" reaction. They seem to opposite terms and actually affecting same things (alveolar diameter/tone); ...
1
vote
1answer
32 views

Sodium-Potassium Pump

From my understanding, in the sodium-potassium pump we have Na+ inside the cell and K+ outside the cell, thus forming a so called "salted banana." After reading my textbook I found many statements ...
2
votes
0answers
15 views

Is it reasonable to assume that RNA polymerase would bind preferentially to the promoter of the long allele of the SERT gene?

I'm trying to come up with an idea for a school project (a hypothetical research study). I'm looking at depression and the serotonin transporter gene, which is highly expressed in the human ...
1
vote
2answers
49 views

carbohydrates and lipids as a source of energy? why?

Why carbohydrates and lipids basically used as a sources of energy? Why only proteins are used as building blocks of all the creations? Yes there are some parts of cells like cell walls in which ...
0
votes
0answers
13 views

What are conditions for a membrane to be settled ? (centrifugation)

The cell membranes have 60% of proteins and 40% of lipids. And we know that medium density of proteins is 1,2 g/cm3 and the medium density of lipids is 0.92 g/cm3. How can we calculate the medium ...
0
votes
0answers
8 views

Is nutrient absorption different in Hypersensitive I patients?

I am thinking how the nutrient absorption differs between between patients with allergies (Hypersensitivity I) and those not. The current guideline about number of eggs in diet is one daily ...
1
vote
1answer
12 views

Function and process of TCTE-1 receptor

I was wondering if anybody knew of the function and process of the TCTE-1 receptor during the binding of a sperm with an egg. The only think I know of TCTE-1 is that it is a species-specific receptor. ...
1
vote
1answer
11 views

Significance of prostaglandins in semen?

I am trying to figure out how prostaglandins in the semen relate to the female reproductive tract. More specifically, How does prostaglandins in semen help the female reproductive tract increase the ...
0
votes
1answer
17 views

What is the function of clot retraction?

I am thinking how clot retraction and fibrinolysis work together. I think that clot retraction is a process that gets clot towards fibrinolysis process. Fibrinolysis process then lyses the clot. ...
1
vote
1answer
21 views

Could mating/recombination be responsible for evolution of entirely novel features?

The diploid chromosomal architecture is rather interesting. For example, because of diploidy we Humans have to mate. Of course in that sense, because diploid organisms often have mate, this has led to ...
2
votes
2answers
106 views

How did the first sexual animal come to exist? [closed]

I am more or less familiar with the evolution theory based on mutations. Now, starting with a nonsexual being, how did the first organism that reproduces sexually come to exist.
2
votes
1answer
21 views

How do beneficial features evolve in species without progressing through detrimental stages?

I'm thinking in particular of wings on birds that would - I'm guessing - have to progress through stages during which they confer no particular advantage. Or is it that all evolved features must have ...
4
votes
1answer
99 views

How do I calculate the change in allele frequency in a haploid population under selection?

From this book For simplicity, let us consider a haploid organism and assume that the frequencies of alleles $A_1$ and $A_2$ are given by $x$ and $y=1-x$, respectively. We also assume that the ...
2
votes
1answer
21 views

Transport of mammalian insulin in vivo

What is the mechanism for transport of insulin in mammalian cells?
2
votes
1answer
54 views

What's the minimum distance of focus for the lens of a human eye to reach maximum flatness?

According to the Wikipedia article on eye accomodation, the range in which a human eye can focus is from 7 centimetres away up to essentially an infinite distance. Of course, people can't see things ...
2
votes
1answer
30 views

Activity of glucokinase

From Solomon et al, 2013 ACC Synthetic biology and from this video : Here, there are 2 competing reactions for glucose - one with glk as enzyme and other with gdh as enzyme. In the graph, y axis ...
2
votes
1answer
105 views

how do they identify different protein chains?

Can someone please explain how different protein chains occur exactly? I'm not talking about the side chain, but the protein chain which is typically labelled as A,B,C etc in the PDB. I'm curious as ...
0
votes
0answers
25 views

Paracentric Inversion and Mutations Question Help Needed

Would someone please be able to help with questons 3 or 4. (one of the at least please) please don't report his as off-topic. first, this is NOT a homeowork question. It's a practice question I am ...
4
votes
1answer
24 views

Can P. falciparum and other malaria parasites be cultured and genetically engineered?

I'm not a parasitologist, and I was wondering about the current state of malaria research. For instance, is it possible to culture P. falciparum? Are there techniques for genetic manipulation, editing ...
1
vote
0answers
26 views

Purpose of certain genes in embryonic development [closed]

(Please correct me if I'm wrong on any count here). As I understand it, development requires the action of numerous genes and proteins. My textbook has described it as being almost reminiscent of a ...

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