2
votes
1answer
58 views

phylogenetic Independent contrasts with unresolved tree

I have a dataset containing morphological and performance measures of species from various groups, including insects, lizards, frogs, spiders etc, and want to analyse the relationship between these ...
0
votes
2answers
67 views

is there a way to do batch download for all gene pathways?

I would like to download all the gene pathways and genes of each pathway. Preferably, gene length of each gene as well. It would be a lot more convenient if there is an R package.
8
votes
1answer
885 views

Is there a protein in the eye that gets kinked by photons and shipped down to the liver to get un-kinked?

My friend made the claim that there exists a protein in your eye responsible for vision. This protein is sensitive to different wavelengths of light, and when it gets hit by the right wavelength, it ...
1
vote
1answer
303 views

What is reductive deamination?

This presentation on anaerobic digestion mentions (pg. 19) two major pathways for the digestion of amino acids: Stickland reaction and reductive deamination. While I find some info on the former, what ...
4
votes
2answers
347 views

What's the difference between naive and memory B cells?

I understand that when naive B cells are exposed to antigens, they become memory B cells, but what is the functional difference between the two? I've looked at the quite a few article on B cells, but ...
0
votes
0answers
72 views

Width of vein in finger

I am working on my bachelors thesis, where one part of it is to find width of vein in fingertip. I use database images and extract vein patterns from it, but i have to calculate the width of vein and ...
2
votes
3answers
175 views

Why doesn't the cytosol dissolve the polar structures?

we know that cytoplasm of cells are filled with water molecules and other hydrophilic molecules so my question is why the water of cytosol doesn't dissolve the ionic part of the lipid bilayer or why ...
2
votes
1answer
234 views

Role of isopropanol in plasmid isolation

In plasmid isolation, isopropanol is used to renature only the plasmid macromolecules after we precipitate all macromolecules(DNA, RNA, plasmids) using sodium acetate solution. How does it do that? ...
6
votes
2answers
298 views

introduction to Chip Seq

I hope this question is suitable for this site. I am concerned about the Chip experiment part so I think it should be okay. I am a Applied Math student starting to get into bioinformatics and so I've ...
3
votes
1answer
169 views

Ideal lab glassware cleaner for molecular biologist

I'm using Alconox powder detergent to clean my laboratory glassware, the powder is a pain to store near the sink and to use. Would like to make a concentrated liquid to use in its stead. I have ...
1
vote
1answer
246 views

Advantage of cup-like shape of blood cells, spores?

Mold spores sometimes have the same shape as platelets in blood. If I were designing a spore it would probably be spherical. Is there any advantage to this cup-like shape? Maybe there is some ...
3
votes
1answer
73 views

How much of the jejunum is bypassed during gastric bypass?

There is both long and short limb bypass surgeries. I want to know how much of the jejunum is bypassed with each procedure.
0
votes
1answer
23 views

What is Saccus in Embryology?

The word seems to be of German origin. I have it here Saccus lymphaticus inguinalis, Saccus lymphaticus jugularis, Saccus lymphaticus posterior, Saccus lymphaticus retroperitonaealis. I ...
3
votes
1answer
88 views

PCR master mix contents

I am running PCR reactions with different sets of degenerate primers and I want to know what should go into the master mix My usual master mix: DEPC water PCR buffer (-Mg) 25mM MgCl2 10mM ...
2
votes
1answer
25 views

Why is oxygen used up in eutrophication?

This probably sounds pretty dumb, but wouldn't algae blooms produce a lot of oxygen? Although they would die out and decomposers would use up oxygen, is that more than what the algae produced?
2
votes
2answers
740 views

Gel Electrophoresis - loading dye and more

I'm a student new to molecular biology coming in from an eco-evo background looking for tips from you molecular pros! It seems that I'm running quite a few gels. The loading dye I'm using is Gel ...
2
votes
1answer
50 views

Is a naive immune system equally able to handle new antigens as an educated one?

This is a variation of the "does the immune system run out of memory" question. Here's a (possibly imperfect) thought experiment: You take two twins. One of them lives in a bubble from birth. One of ...
3
votes
0answers
41 views

How is nutrient uptake in humans measured? [closed]

There are many claims made about nutrient absorption, eg "Juicing helps you absorb all the nutrients from the vegetables". I'm curious to know how nutrient uptake is measured. Eg is it a pure ...
3
votes
1answer
95 views

What is meant by single molecule sequencing?

When sequencing papers refer to single molecule sequencing, what is their definition of a "molecule". Are they saying base by base? The entire DNA chain in a chromosome can also be though of as a ...
2
votes
2answers
232 views

How were the first primers made

I keep reading about how primers are useful in pcr -- they allow you to select a specific dna region. Similarly, in NGS or Sanger sequencing they give you a starting point. The primers I see are about ...
3
votes
1answer
88 views

How does regurgitated food go to the 3rd stomach chamber instead of going to the 1st?

Ruminants are known for their regurgitation of food; the food goes through the 1st and 2nd stomach chambers, then returns to the oral cavity in cuds. The cuds then come back into the stomach, but this ...
4
votes
1answer
33 views

When does exposure to an allergen increase / decrease allergy?

In immunotherapy a person is regularly exposed to an allergen to decrease the allergy. Yet apparently "repeated intranasal challenges ... induces robust allergic airway inflammation, " [0] So when ...
0
votes
4answers
545 views

Strictly from a biological perspective, what is the functional expectation of a human being [closed]

Just like the title says: Strictly from a biological perspective, what is the functional expectation of a human being. No religious or philosophy-based answers will be accepted, we are talking ...
0
votes
1answer
100 views

What is accumulation and release centre of neurohormones?

What is accumulation and release centre of neurohormones? Is it hypothalamus?
4
votes
1answer
602 views

Identical twins' biological sexes

Can identical twins have different genders (as in biological sex)? I thought they should have absolutely the same genes. If they can, what caused it? I'd assume it MAY be because of errors in ...
2
votes
1answer
198 views

What kind of small insect is this?

Found in central florida in the bath tub. Its about the size of a pencil marking, very small. What is it?
2
votes
2answers
96 views

Is there a name for this principle in biological contexts?

This is mostly a question about usage. There is a probability-related idea that has been used in at least two biological contexts. The idea is that if something happened, it was probably likely to ...
6
votes
2answers
209 views

How would the human body adjust to sleep times if we were to live in a place with different day lengths?

You sleep at night and are active during the day that's how things work for humans, but theoretically if a human whose parents lived on earth were to be born in another planet resembling earth but the ...
6
votes
0answers
46 views

Effect of Aging on SA node's sympathetic fibers

I am trying to understand the effect of aging on the sympathetic fibers of SA node. I know that aging shifts the vagal curve to left in frequency due to aging. However, I am interested if aging has ...
4
votes
3answers
339 views

What does “kcal/mol” mean when speaking of enzyme catalysis?

After thinking about it, I'm confused by what the reaction barrier of an enzyme actually means. Imagine a reactor containing enzyme and substrate. If the enzyme in the reactor has a reaction barrier ...
1
vote
1answer
27 views

Detecting a Fasting State in the Body via Lasers

I was just wondering wether it would be possible to detect if the body is in a "fasting" state, via lasers attached to the body. If it is possible, what sort of laser would be needed?
1
vote
2answers
54 views

How do exon tandem exon duplications occur in the genome?

By this I mean in cases where tandem exons are introduced by replication slippage how would a DNA polymerase by chance duplicate an entire exon cleanly (i.e. from exact start to exact end) when it ...
1
vote
1answer
145 views

Heterozygosity and overdominance

Consider $m$ loci with heterozygote advantage (overdominance) such that the fitness of the two homozygotes is $1-\frac{s}{2}$ and the fitness of the heterozygotes is $1+\frac{s}{2}$, where $s>0$. ...
5
votes
2answers
300 views

Why haven't land animals evolved beyond urination?

It occurred to me (while urinating) that this would seem to be selected against because water is a scarce resource. Why are we constantly losing water we don't need to through urination? What is ...
2
votes
1answer
49 views

How are new chromosomes replicated into the next generation via sexual reproduction?

If an individual has a new chromosome, which is very unlikely to happen, he will not have any luck in finding a sexual partner with this same trait. How will the offspring inherit this trait. And ...
8
votes
1answer
390 views

List of np-hard problems in biology/bioinformatics

I'm not sure if this is the right place for this but... I am looking for a list of computationally "hard" problems such that if a problem from this list could be solved effectively, it would be ...
2
votes
1answer
119 views

Could someone Identify this Insect Hive on my Balcony Grill

A smallish insect hive has been forming on the grill of my balcony in the last month or two, and I wanted to know should I be worried or can I just let it be. Its 13th floor in Singapore, if the ...
1
vote
1answer
469 views

In an open circulatory system, how is blood moved?

In the mollusks section, the powerpoint mentioned that gastropods and bivalves have an open circulatory system. According to the note, this means that the blood does not travel in vessels. How, then, ...
4
votes
2answers
582 views

How can CI repressor both activate and repress $P_{RM}$ promoter found in $\lambda$ phage?

I'm reading a paper where the authors constructed a toggle switch that uses bidirectional $P_R/P_{RM}$ promoter found in the $\lambda$ phage. There are 3 binding sites - $O_{R1}$, $O_{R2}$, $O_{R3}$ - ...
-2
votes
1answer
148 views

Punnett square and hybrid cross [closed]

A plant breeder crossed two plants, one with red flowers, and the other with white flowers. Red is dominant. Calculate the phenotype and genotype ratios of the F2 generation of this cross. Is this a ...
1
vote
1answer
118 views

Percentage of understood human DNA [closed]

I want to know what's the approximate percentage of understood human DNA, as in, which part does what. I'm not asking for details, just the amount. Thank you.
-1
votes
1answer
83 views

Effect of nerve pills and relationship to Shingles [closed]

Do nerve pills actually suppress the nervous system and how would that effect the Shingles virus which is known to activate under large amounts of stress?
2
votes
1answer
73 views

Speed of effective lymphatic drainage?

Lymphatic drainage occurs from many portions of the body: To venous angle: head axillary lymph nodes hands abdomen legs (I think legs' drainage goes through abdomen) The speed of the lymph ...
2
votes
1answer
82 views

Do any nonhuman species have effective ebola immunity?

I've read that ebola is an effective killer in humans because it has the ability to interrupt dendritic cells from manufacturing proteins that cause the immune system to destroy the dendritic cells ...
0
votes
1answer
27 views

How is bacterial plasma membrane made?

Eukaryotes have ER which manufactures plasma membrane of cells. How is prokaryotic plasma membrane made ? What is the pathway and which enzymes are involved ?
3
votes
2answers
447 views

Why does methylation not occur in viral DNA?

Why does methylation not occur in viral DNA? Can viral DNA undergo the process of methylation? If not then why does this process does not occur in viruses?
3
votes
0answers
84 views

What is the main challenge in creating a chemical male contraceptive?

More than 50 years after hormonal contraception for women was invented, a contraceptive pill for males is still not available. With the obvious major biological differences in mind, why does it appear ...
2
votes
1answer
216 views

List of heritability estimates in humans?

Many people on this site ask questions that directly or indirectly have to do with heritability in human. Do you know a list of estimates of heritability of various traits in humans? Or could you try ...
1
vote
1answer
45 views

Why doesn't the avocado turn brown when it is kept with its seed?

Why doesn't the avocado turn brown when its kept with its seed? What does the seed release that slows down the oxidation process?
4
votes
3answers
124 views

Book recommendations for evolutionary models

I was recently working on getting a statistical model of a DNA sequence. To do this I found that understanding evolution quantitatively seems to be quite important. I would really appreciate any book ...

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