3
votes
1answer
40 views

Seed Dormancy and Seed Transportation

My textbook says "As the seed matures it loses water and enter dormancy". I am confused as to whether this happens before the seeds are transported or after, and as to how seeds know to become dormant ...
0
votes
1answer
60 views

estradiol hormone role

Increasing estradiol (E2) hormone from ovarian follicles prior to ovulation has been hypothesized to play a critical role for induction of pheromones. These pheromones render females sexually ...
1
vote
1answer
220 views

Codon alignment via Python? [closed]

I have pairs of coding DNA sequences which I wish to perform pairwise codon alignments via Python, I have "half completed" the process. So far.. I retrive pairs of orthologous DNA sequences from ...
2
votes
2answers
95 views

Molecular simulations without capping n- and c-terminus of polypeptide

When running molecular simulations, what is the consequence of not capping the n- and c-terminus? I have been following gromacs tutorials and haven't come across any that deal with capping the ...
4
votes
2answers
117 views

Is tactile perception two-dimensional or three-dimensional?

Is tactile perception two-dimensional or three-dimensional? Can tactile sense be mapped on 2-dimensional map of the surface of the human body or does human receive tactile signal as a 3D position ...
3
votes
1answer
567 views

When happens when pollen grains land on the a part other than the stigma of a flower of the same species?

When happens when pollen grains land on the a part other than the stigma of a flower of the same species? Would the pollen be transported to the stigma or would it just sit where it landed and nothing ...
1
vote
2answers
1k views

What does dominant generation mean

In my texbook it is written that for non- vascular seedless plants the dominant generation is the gametophyte as the gametophyte generation is larger and longer lived. Is the criteria for dominant ...
4
votes
1answer
320 views

Sporophyte and gametophyte

My textbook says that in both groups of seedless plants (vascular plants, non-vascular plants) the gametophyte is a free-living plant, independent of the sporophyte. I don't understand this statement ...
1
vote
1answer
137 views

Why do some animals and fungi prefer asexual reproduction?

Animals like Sponges and Hydra and fungi like Yeast and Mushroom can reproduce both asexually and sexually. However, they only reproduce sexually if the 'circumstances' are 'bad'. Is there a specific ...
2
votes
1answer
43 views

ligand binding fluorescent protein

does anyone know of a fluorescent protein that upon binding of a substrate its fluorescence is activated? i've been looking on this and perhaps my keywords are not the right ones. Thanks in advance
9
votes
3answers
2k views

Why did abiogenesis only happen once?

If the "primordial soup" theory of abiogenesis is to be believed, self-reproducing organisms spontaneously arose on Earth at least 3.5 billion years ago, surprisingly soon after the Earth cooled down ...
2
votes
2answers
1k views

Can more than one antibody bind the same antigen

I'd like to clear something up about antibodies that I'm not sure I've understood in the articles I've read. Looking at concepts such as "affinity maturation", "monovalent antigens" and "polyvalent ...
1
vote
1answer
133 views

Studying the fruitfly nervous system

I'm studying Neuroscience and Fruit Flies are a pretty big deal but I don't know as much as I think I should about them. Are there and comprehensive sources that I could read? I'd like a review of ...
4
votes
1answer
138 views

Identification of this spider?

I find these in forests in Oregon, western half, though they're probably on the eastern half as well. They live under pieces of wood and bark, and have a small web across the ground. Mine will eat ...
2
votes
2answers
228 views

Book recommendations for algorithms used in evolutionary biology

Do you have recommendations for a book that presents the different algorithm used in theoretical evolutionary biology? I don't mean evolutionary or genetic algorithms (otherwise this question would ...
4
votes
1answer
48 views

Where are newly discovered medicines tested

When a medicine is prepared by a biologist,then where does he first test on? And how does he know that this is the exact combination for a disease to get cured? Does he test that medicine on a human ...
4
votes
3answers
925 views

Is lemon water an alkalizing agent in the body?

I was recently having a discussion with someone about whether lemon water actually increases the pH of your body (by which I assume they mean the blood); their claim was that once Citric acid was ...
2
votes
1answer
68 views

Speciation and Phylogeny of Lactobacillus

The lactobacillus, also called Döderlein's bacillus is a genus of facultative aerobic bacteria. There are several species such as Lactobacillus acidophillus and Lactobacillus reuteri. I have several ...
0
votes
0answers
28 views

Stress regulation in mosquitoes

I was just trying to understand how in insects, specifically mosquitoes does the process of emergency responding, stress regulation take place? Or in simpler words how are flight, fright and fight ...
3
votes
1answer
571 views

Ka/Ks (dN/dS) analysis module for Python?

From this wiki article: In genetics, the Ka/Ks ratio (or ω, dN/dS), is the ratio of the number of Nonsynonymous substitutions per non-synonymous site (Ka) to the number of synonymous ...
7
votes
3answers
235 views

How should I put a large phylogeny into a scientific paper?

I've been trying to put a phylogeny tree into a scientific paper. This tree includes ~220 species, which is too too large for one page for journal articles (Letter or A4 size). But in my paper it is ...
1
vote
1answer
59 views

Clownfishes and Sea anemones

Relation between clownfishes and sea anemones is a classic example of mutualism. I wanted to list the species of sea anemones that are involved in this mutualism but I got lost.. Could you help me ...
5
votes
4answers
275 views

Why has evolution made neurons use spiking?

I'm going to be forward and say that I'm not a biologist. I don't claim to fully understand the functionality of a neuron from an electrical/chemical perspective... I'm curiously gazing from the ...
8
votes
1answer
134 views

Dogs bark at familiar person in Santa costume. Why? Don't dogs trust smell over vision?

Last night 10 humans and 2 dogs spent Christmas together. At some point, one human dissappears for a few minutes and comes back wearing a full Santa outfit. Upon respawning, the dogs start barking ...
5
votes
3answers
105 views

Identifying whether ELISA kits are authentic or fake

What methods can be used to determine whether they are authentic or fake?
1
vote
0answers
20 views

When do chimeras happen?

If one developing twin absorbs another, when does that happen? Is it possible for an appendage or organ to develop and be the only remaining vestige of an absorbed twin, such as a hand or a mouth, or ...
3
votes
1answer
113 views

Is there a limit to twinning?

Can developing twins further divide and subdivide and become identical quadruplets or octuplets or...? Can twinning be induced, either in utero or in vitro? Might it be possible to just keep ...
2
votes
1answer
113 views

When does identical twinning happen?

What is the window during which division into twins is possible (for instance can it still happen after implantation in the uterus)? Is one twin the "original" and the other its clone?
3
votes
1answer
48 views

Why genes are assumed to follow multivariate normal?

I wonder why gene expression data are very frequently modeled by multivariate normal distributions. What is the reason for those strong assumptions that the genes follow multivariate gaussian? Are ...
2
votes
1answer
92 views

The arrangement of retinal cells?

The section of retina shows a layered arrangement of the various retinal cells. Starting from the inside (where the light strikes first) is the nerve fibre layer, ganglionic layer, amacrine cell ...
-1
votes
2answers
92 views

Why it is rare for person to get infected with two Pathogens?

Why is it rare for a person to have 2 (or more) infectious diseases (for example: Flu & Cold together at the same time)? Although it's rare, it happens when the immune system is weak (e.g when ...
6
votes
1answer
50 views

Are original x-ray diffraction data available

Is it customary for investigators to publish the original x-ray diffraction data used in macromolecular structural determination? If not, why not; and if so, is there an online database where these ...
7
votes
1answer
207 views

Can cancer cells in the same person, organ, and origin have different DNA?

Is it possible for cells from the same tumor to have different genetic material, and if so, to what degree is it possible (how fast do they mutate) ?
3
votes
1answer
107 views

How Much Longer For The Gene For Blue Eyes?

In the year 1900 roughly 50% of the people in the United States were homozygous for the gene for blue eyes. By 1950 the number had dropped down to 30%. Just now, (2013) barely 12% of the people living ...
4
votes
2answers
198 views

How do detergents get in hydrophobic membrane interior?

According to Molecular And Cellular Biology (Stephen L. Wolfe), Membranes disperse almost instantaneously if exposed to a nonpolar environment or to detergents, which are amphipathic molecules ...
5
votes
2answers
88 views

Is the empty GI tract a hollow tube with air inside, or is it generally collapsed until food is eaten?

I have heard that "air in the GI tract" results in flatulence and burping etc, however I initially assumed that the "empty" GI tract was a hollow tube filled with air anyway. So on an empty stomach ...
1
vote
1answer
46 views

Is this maritime plant a species of zostera?

This photograph was taken on the intertidal mudflats at Lindisfarne, Northumberland, UK today. It was about 40m from the shoreline at low tide. Is the green plant a species of zostera? Can anyone help ...
2
votes
2answers
181 views

Are there free electrons in muscles, hair, or skin?

Electric shock occurs upon contact of a (human) body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair. In metals many electrons are said to be ...
6
votes
2answers
9k views

Why is dimethyltryptamine (DMT) being released during death?

I'm not very well informed about all the things related to biology and the current achievements of science in this field so if I'm wrong in anything I say, please let me know. Many times I've come ...
1
vote
0answers
36 views

How far does the diaphragm stretch when it contracts?

I have been wondering about this for this entire day today and I can't seem to find an answer. How far, exactly, does the diaphragm stretch for tidal breathing and what is its maximum stretch length?
0
votes
1answer
103 views

Current human behavior as a genetic heritage

People: I have doubts about genetic heritage, but let me explain the context which has shown up this doubt for you: I was debating about sexism and the following question were put on the discussion: ...
1
vote
1answer
102 views

Determining limiting nutrients from a graph

The question was Which of the following statements is supported by these data? A. Phosphorus was the first limiting nutrient followed by nitrogen. B. Nitrogen was the first limiting nutrient ...
0
votes
1answer
78 views

How does a prophage leave the host cell's genome?

I understand that, unlike a prophage, a provirus never leaves the genome, but I don't understand how the prophage "leaves".
2
votes
1answer
208 views

Is light required for seed germination?

Is light required for germination of every seed? If not, why don't some plants require it? Is there any difference in the quality and duration of light required ? It would be interesting if someone ...
1
vote
1answer
91 views

What is a phospho-protein binding domain?

Is this just a domain that binds proteins that have been phosphorylated? And it mediates signalling between an activated/phosphorylated protein? How is this significant with BRCA1?
1
vote
1answer
87 views

Colchicine addition to cells

When is colchicine added to dividing cells for karyotype studies? I know that colchicine inhibits polymerization of microtubules. 2 So, why should it stop the cell cycle at metaphase when ...
1
vote
0answers
139 views

Transcription takes place from the 5’ to the 3’ end of the m-RNA. Why?

Only one side of the DNA ladder is copied (the sense side). The sense side starts with a 3’ end. This means the corresponding mRNA will have to assemble starting from the 5’ end. This is my initial ...
3
votes
1answer
43 views

When was it determined that Type 1 Diabetes is an autoimmune disease?

I just found out today that type 1 diabetes is an autoimmune disease. When was this discovered?
5
votes
2answers
69 views

Standard Classification of Disease

I am working on a project for health center. It involves the creation of a database of all diseases. Currently I want to classify disease on the base of their category based on international standard. ...
1
vote
0answers
47 views

Paired-end mapping exercise

Pair-end mapping (PEM) is a technique that allows to detect structural variants in DNA by obtaining paired-end reads and the comparison of their positions in a reference genome. Then among libraries ...

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