0
votes
0answers
1 view

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
6answers
118 views

Which information can be obtained from a list of gene names?

Lets say I only have a list of gene names. I know they are up regulated and I know they are related to cancer. What information can I obtain from having only the names of genes? For example is there ...
3
votes
1answer
28 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 ...
0
votes
1answer
10 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 ...
1
vote
1answer
40 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
45 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
20 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 ...
5
votes
1answer
44 views

What recovers normal polarisation after hyperpolarisation?

I have been taught that a Na+/K+ pump helps to recover normal polarisation after hyperpolarisation in neurons. I could not find out how it does that, since I've also been taught that such a pump moves ...
3
votes
2answers
44 views

Terminology for inefficacy of selection on recessive alleles

I am wondering is there some proper terminology which is used to say that deleterious recessive alleles might be able to hide, reducing the the efficacy of selection, in diploid organisms/chromosomes. ...
1
vote
0answers
24 views

Why my right eye see warmer colors

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 ...
1
vote
0answers
18 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? ...
4
votes
0answers
9 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
12 views

planting conifers in a sagebrush area

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
1answer
42 views

Which sources can I use to study botany and horticulture?

I refer with this question to those among you who have a strong background and work in fields like: botanics, horticulture, dendrology, etc. I would like to start building a solid preparation, both ...
2
votes
1answer
54 views

About validation process of phenological study

I have recently done a phenological study using remote sensing techniques. Now I need to validate my results and my methods, that is, to determine if the phenology estimated from remote sensing is ...
12
votes
2answers
1k views

The Uniqueness of DNA Paradox

How can everyone have unique iris and fingerprints? After a certain amount of human beings have lived on earth, wouldn't it be possible to exhaust all possible combinations? The same principle ...
4
votes
2answers
278 views

What determines the autumn leaf color?

It is autumn out there. Green, brown, red, yellow, and mixed-colored leaves drop from the trees to the ground. What determines the colors of the leaves? Wikipedia tells me Leaf senescence is the ...
2
votes
0answers
19 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 ...
3
votes
3answers
49 views

Can systemic intravascular thrombosis cause brain infarction?

I wonder if the thrombus can pass through the brain-blood barrier because I think small molecules like O2, CO2 and ethanol can pass it. Probably, in some diseases where the permeability of the barrier ...
6
votes
2answers
368 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 ...
6
votes
3answers
48 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 ...
3
votes
1answer
16 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 ...
0
votes
1answer
36 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 ...
4
votes
1answer
45 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 ...
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 ...
3
votes
0answers
18 views

What would the blood work look like for someone on a very high protein diet?

What will blood test results look like for someone on a very high protein diet consuming 1-2g of protein per pound of bodyweight per day? Is it healthy to maintain such a diet?
2
votes
2answers
3k views

Is episome a plasmid or a virus?

A plasmid is a small DNA molecule that is physically separate from, and can replicate independently of, chromosomal DNA within a cell. In general, in eukaryotes, episomes are closed circular DNA ...
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, ...
4
votes
2answers
115 views

Do animals exist which have great vision, but see only grayscale?

In computer vision the color information is often discarded, as most object recognition tasks seem to work just as well on the greyscale image (even better, because there is less unnecessary ...
1
vote
0answers
15 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 ...
3
votes
1answer
27 views

Is RNA polymerase affected by proteins bound to the coding sequence of a gene?

I am designing a synthetic gene construct to express genes in E. coli driven by either Ptet or PLacO. The construct would look like: -Ptet-(Gene1)-PLacO-(Gene2)- I want to express each gene using ...
6
votes
1answer
66 views

How can one accurately diagnose the cause of human hearing loss without surgery?

In a human, if you were to avoid a tympanotomy (surgical examination of the middle ear), how could you distinguish between a blocked Eustachian tube, a ruptured eardrum, or a perilymph fistula? For ...
2
votes
1answer
18 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 ...
1
vote
0answers
12 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
32 views
21
votes
3answers
361 views

How is the blood volume of a living organism measured without killing it?

How is the blood-volume of an organism measured without killing it? Note:The blood-volume of an organism is defined as the total volume of blood present inside that organism.
9
votes
2answers
4k views

Why does it hurt when you take sweets, if you have cavities in your teeth?

When you have cavities in your teeth taking any sweetend drinks or food causes sensitivity or pain. What could be the reason?
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 ...
3
votes
2answers
55 views

Why “broad” instead of “large” cross-immunoreactivity? [on hold]

From the articles I read, expressions like "broad cross-immunoreactivity" pops up a lot. So, I was wondering, why "broad" is used here instead of large? Is there a specific reason?
2
votes
1answer
38 views

Help reading gene markers

I'm sorry if "gene markers" is not the correct word. An edit could be appreciated but I don't study in an English speaking country unfortunately. Question overview: In a family, there is a genetic, ...
2
votes
0answers
46 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 ...
-2
votes
0answers
65 views

Epicanthic fold (eye)

What evolutionary advantage does the epicanthic (eye) fold provide? I know that the incidence of epicanthic folds is high in Central, East, and South East Asian populations, Mongolians, Inuit, etc. ...
7
votes
1answer
792 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 ...
1
vote
1answer
25 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 ...
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). ...
5
votes
2answers
50 views

Immediate stroke/seizure Therapy

Can an oncoming stroke/seizure, be stopped by a setup consisting of a brain-computer-interface (BCI) that immediately detects the variation in wave-form, and then another machine that neutralizes the ...
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 ...
8
votes
1answer
70 views

What processes are responsible for focusing on an image only seen by one of the eyes?

When a person is spying from around a corner with only one eye, it's rather easy to ignore the other eye's image, since it's probably much darker, because one usually spies around a corner standing ...
6
votes
1answer
58 views

How does the frequency of a visual stimulus affect the steady-state visually evoked potential?

I want to design a project for EEG signal processing. In my research I found the concept of SSVEP. SSVEPs represent the electrical activity of the brain as measured via EEG, and are evoked by visual ...
3
votes
0answers
26 views

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 ...

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