3
votes
0answers
10 views

How to tackle Winfree's “The Geometry of Biological Time”

I am trying to read through "The Geometry of Biological Time" and I am having a hard time understanding the geometric concepts provided in the book under context of biology. Can someone who has went ...
1
vote
2answers
9 views

Recessiveness of allele for protection of organism

Heterozygous organisms profit from pairs of gene alleles. Harmful alleles when being recessive can be carried without any harm for the organism. Only when two harmful recessive alleles form a gene the ...
3
votes
2answers
62 views

Why does an electrical shock freezes up the muscles?

Why is it when someone comes into contact with an electrical supply that their body freezes up and is unable to move away from the electrical source? Can someone explain this through physiological ...
0
votes
1answer
14 views

Factors on which one compound transforming to another compound depend

Considering the Metabolic Pathway: http://www.genome.jp/kegg-bin/show_module?M00166 Consider the reaction R01523(the very first reaction). How is it possible to know that the compound ...
3
votes
1answer
43 views

Why cannot there be multiple sources for same species origins?

We often associate Africa as the geographical location of the origin of humans. Why cannot there exist multiple geographic locations of origin (given same environmental conditions)? The same ...
3
votes
0answers
18 views

Is biological clock of humans genetic or learnt?

Argument favouring learnt: A child, when born sleeps for 20-22 hours. But he learns to manipulate his timings to night and according to his and family needs. Some sleeps 1 am to 7 am, some from 11pm ...
0
votes
1answer
8 views

18S rRNA sequence

I have this phenomenon that the human 18S rRNA reverse transcribed with polydT oligos serve as faithful RTPCR normalizers, tested with better known house keepers. I want to know what I'm amplifying ...
1
vote
0answers
12 views

How to seek for available genetic data relevant to ecology and evolution?

I am asking for advice on how to search for available genetic data that can be used for research in ecology and evolution. I am asking a general question and then for a study case question. I had a ...
2
votes
3answers
132 views

Where does the term “cos site” come from?

The word cosmid is derived from cos sites of lambda phages. Why are cos sites called cos sites? What does this "cos" refer to?
0
votes
1answer
14 views

Can sugar be absorbed orally within seconds? [duplicate]

Whenever I feel a little light headed or tired, it helps to eat something sweet. Specifically, simply chewing or sucking on a sweet seems to aleviate the symptoms within a matter of seconds and then ...
-1
votes
0answers
16 views

Are there examples of abnormal human chromosomes that can cause diseases? [on hold]

I was looking into chromosomes and I found the chromosomal abnormalities. I have a limited understanding but I was wondering if someone could clarify it? I was also wondering what numerical, genetic, ...
0
votes
1answer
13 views

Is missing Q wave characteristic for Wolff-Parkinson-White Syndrome?

No my study books says about that no Q waves in WPW syndrome. They are about wide QRS complex often however. I heard today that the characteristic property of WPW is often a missing Q wave, like here ...
2
votes
1answer
32 views

Evolution and Phenotypes.

This may be better suited for the English language SE, but When discussing evolutionary changes in species is it proper to refer to their phenotypes? In this context: "Imagine if a cow did not ...
-6
votes
1answer
64 views

What is the biological process shown in this textbook cover? [on hold]

So I've been with this question to a number of forums and I can't seem to get any head start with it. I have this textbook called "The World of The Cell" 7th ed. On its cover is a picture that is ...
7
votes
1answer
95 views

Is Batesian mimicry more important for females?

Myrmarachne plataleoides is a jumping spider that mimics the Kerengga or weaver ant (Oecophylla smaragdina) in both morphology and behaviour. However, the two sexes appear different: Myrmarachne ...
2
votes
1answer
17 views

Why does the inhibition of translation initiation cause the accumulation of 80S ribosomal monosomes?

As I have read in (1), inhibition of translation initiation will increase the number of 80S ribosomes while decreasing the fraction of polysomes due to the polysome-runoff. The net effect is to ...
-1
votes
0answers
11 views

What causes co-dominance and incomplete dominance to occur among two alleles? [on hold]

Are they mutations? Do they occur in all species or only in hybrids? Why?
0
votes
0answers
5 views

How the pattern of fertilization path is determined before the cell division to form the blastocyst? Is it individually specific?

After sperm meets ovum,the inactive nucleus starts following a particular path inside the zygote, kind of chasing a path. This path biologically known as fertilization path. But my question is how the ...
2
votes
1answer
63 views

Which wavelength to use to determine algae using a colorimeter?

I am doing a Biology project involving the measurements of the density of algae (Nannochloropsis) using absorbance colorimetry. What wavelength should I set my colorimeter to? The issue is that there ...
2
votes
2answers
60 views

What are the “minimum requirements” for a single cell?

I saw a description of the "minimum requirements" for a cell at http://creation.com/origin-of-life in the section called "What are the minimum requirements for a cell to live?" and I'm wondering if ...
6
votes
1answer
50 views

Why are abiogenesis and evolution considered unrelated?

When a discussion about evolution comes across abiogenesis - the typical reaction is that they are unrelated (see the headline at http://www.factsnotfantasy.com/abiogenesis.php). It seems to be ...
1
vote
0answers
41 views

Why my right eye see warmer colors? [on hold]

As the title says, my right eye see warmer color than the left one. I've seen a few people talking about that thanks to google, but I was unable to find a proper answer. So, what cause this strange ...
4
votes
0answers
17 views

Is it possible that the vapour form of propylene glycol could lower a humans blood oxygen saturation by the manner in which N2O does?

My understanding is that by inhaling nitrous oxide leads to the body not being able to take in as much oxygen as it usually would. Is it possible that a heavier soluble gas such as the vapour form of ...
1
vote
0answers
16 views

planting conifers in a sagebrush area [on hold]

I'm looking at buying some property in the picture below. You can see the conifers (mainly Jefferson Pine and Lodgepole Pine) as the dark green dots on the outside frame. The intersecting line (top to ...
2
votes
0answers
24 views

External sensory stimuli that awaken a person from sleep

An external sound or touch can awaken someone. Can a light? It would have to be very strong, but part of the reason might be that it would have to penetrate the eyelids. And can a smell or taste? ...
3
votes
1answer
49 views

How do bumblebees and hornets avoid the negative effects of inbreeding?

I just learned that all hornets and bumblebees except for the queen die at the end of the year and the queen starts a new nest in spring. But that means the next generation of queens have only ...
2
votes
1answer
57 views

What would be required to evolve an animal (non-human) brain to obtain human-level cognition?

Could any animal subject to the right conditions evolve human-level intelligence? Suppose that an artificial intelligence (AI) decided to artificially evolve a population of octopus (don't ask why, ...
3
votes
1answer
17 views

How exactly is glyceraldehyde 3-Phosphate reverted to ribulose 1,5-bisphosphate for the continuation of the calvin cycle?

Around 6 molecules of G3P is produced at the end of the Calvin Cycle (light independent reactions of photosynthesis), and 5 of which are reverted back to RuBp. The general equation that I read is 5 ...
6
votes
2answers
371 views

How sterile is sterile when working with nucleic acids to prevent contamination?

I am reading up on preparatory work on working with nucleic acids and a lot of the instructions speak on excessive procedures on cleaning environments with high %ethanol and making sure the equipment ...
7
votes
3answers
51 views

Current along an axon

When an action potential is induced on a neuron, the local transmembrane potential jumps from $E_{\mbox{rest}}$, the resting potential of the neuron, to $E_{\mbox{eq}}$, the equilibrium potential of ...
0
votes
1answer
39 views

Does “mind” has any physical reality in biology? Or is it just an assumptive concept?

Biologically, Brain controls our thinking, ideas, decisions everything along with controlling each body parts. My question is, is there anything real as "mind "? If it's controlled by brain then ...
2
votes
0answers
8 views

Is the blastocyst a coeloblastula?

A coeloblastula is that type of blastula which has a fluid filled cavity. Since the blastocyst of the mammals does too, can it be called a coeloblastula? My book however mentions the two as different, ...
3
votes
1answer
48 views

Why can action potentials not be initiated at dendrites?

Why are action potentials not initiated at dendrites, although dendrites are the first to receive input from the presynaptic cell? In fact, excitatory postsynaptic potentials (EPSPs) at the dendrites ...
1
vote
0answers
16 views

classical conditioning paradigm for hippocampal learning

I wanted to know what a suitable classical conditioning experiment would be to analyze learning and memory capabilities in rodent models with respect to hippocampal long-term potentiation. For ...
1
vote
0answers
13 views

Brain regeneration - book recommendation

Searching for an up-to-date book on regenerative brain medicine with a focus on stem cell therapy. In addition, I am interested in modeling of the micro environment and genetic engineering of neuronal ...
-8
votes
0answers
35 views

Why do we have buttocks at the back and not in the front? [on hold]

We have buttocks at the back and not in the front. Why? edit: I mean, why is gluteus maximus bigger than inner hip flexor?
2
votes
1answer
20 views

What is the protein sequence taken as input in the Path-A prediction system

Considering the Path-A based metabolic pathway prediction (http://nar.oxfordjournals.org/content/34/suppl_2/W714.short). It uses machine learning for pathway prediction. Suppose that the input was a ...
4
votes
1answer
46 views

Relationship between toxicity of drugs and negative effects on brain

Are psychoactive drugs with lower lethal doses more neurotoxic (more damaging to the brain)? For example, tetrahydrocannabinol (one of the active components of cannabis) has a much higher lethal dose ...
6
votes
2answers
43 views

Is there a name for the evolutionary loss of vestigial structures?

Consider a biological structure which no longer benefits an organism, such as the eyes of an organism whose population now lives in total darkness. I can think of three reasons why such a structure ...
7
votes
1answer
799 views

Term for trait that is advantageous to a population only as long as it is rare

I remember reading about a concept—in evolutionary biology or natural selection, I think—whereby a particular trait is advantageous to the population or species but only so long as that trait is only ...
6
votes
0answers
24 views

THYROGLOBULIN (19S) comes to a heavier position than ferritin (51S). Why?

Sedimentation values of thyroglobulin and ferritin containing iron are 19 and 51S, respectively. But, by density gradient centrifuge, it seems thyroglobulin(19S) migrates faster than ferritin(51S). ...
3
votes
0answers
38 views

When and How do pacemaker cells develop during the cell aggregation process of Dictyostelium discoideum?

I was reading a paper by Tang & Othmer about oscillations and waves in Dictyostelium discoideum. Under certain condition like starvation period in the life cycle of a Dictyostelium discoideum ...
-3
votes
0answers
41 views

Is it theoretically possible to be immortal? [on hold]

I have little idea about gene sequence reading and missing of a particular code in every reading. Is that main key of aging? I mean is telomere partly responsible for this? How can we stop aging?
6
votes
1answer
27 views

How is it determined in a zygote state of foetus, that which side is mouth and which side is for anus?

After the fertilization when the zygote is in the growing state to a foetus, the main canal is introduced first, from mouth to anus. But my question is when the canal is created first how does it ...
1
vote
0answers
58 views

Why do I smell chlorine when my sinuses are clogged? [on hold]

I constantly smell chlorine after blowing my nose. I know it has to do with the sodium-chlorine ion channels but I don't know exactly what role they play. Related: I know in the disease "cystic ...
2
votes
1answer
20 views

Why Sister Chromatids and Daughter cells and not brother chromatids and son cells

In biology why do we have terminologies in terms of female relatinships such as daughter cells and sister chromatids and not in terms of male relationships. When did this custom started and is there a ...
3
votes
1answer
58 views

Why does a lack of sleep degrade my balance?

For years, I've noticed that the day after a night of poor sleep (4 hours or less), my balance noticeably degrades. For instance, while walking 20 feet to the coffee maker, I might stumble into the ...
2
votes
0answers
47 views

What effects would be caused by exposure to common life forms with opposite enantiomer biology? [on hold]

Pretend a human had their body "reflected": heart on the wrong side, etc.; but also at the biochemical level: proteins, sugars, cells, DNA, everything. What would the effects be of that human's ...
1
vote
1answer
26 views

What is the trigger of pollen tube formation when the pollen is on the stigma? [on hold]

What is the mechanism of pollen tube formation when the pollen is close to the stigma ? Is it because of chemotaxis? In other words, is the growth triggered by some chemical substance that is ...
2
votes
1answer
10 views

Do I have to use sucrose to induce a lac promotor?

I'd like to optimize the expression of a Fab fragment in Escherichia coli. For induction of the lac promotor on the pAK400 vector I use IPTG and sucrose. Do I optimize the expression in case I would ...

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