0
votes
0answers
27 views

How to increase contrast with only a top entry specimen holder

My question is: If my microscope had a top entry specimen holder, instead of a side entry holder, what additional option(s) should I have to increase the contrast with the same constraint that I only ...
2
votes
1answer
136 views

Why is oxaloacetate made in the mitochondria?

I'm looking at the gluconeogenic pathway: Pyruvate is shuttled into the mitochondria from the cytosol, converted to oxaloacetate by pyruvate carboxylase, converted to malate which is then shuttled ...
2
votes
2answers
363 views

How can we know or measure pain in animals?

Is there any standard way to know how much pain an animal feels when it gets hurt like when a bird loses it's wing or hen when killed etc. All pain sensation points? Hey I'm new to biology. :)
3
votes
1answer
38 views

What is the purpose of narwals' tusks?

I've heard that narwals can grow their tusks up to 16 ft long. What do they need the tusk for? Hunting? Comunication?
1
vote
2answers
390 views

How does the size of insert affects the rate of Homologous Recombination in yeast?

When performing genetic knockouts in yeast using homologous recombination to replace a target gene sequence via a vector DNA, does the region between the flanking regions in the vector have to be the ...
3
votes
1answer
38 views

DNA replacement: new species

This is a hypothetical question What would happen if the DNA of a prokaryote was replaced with the one of a prokaryote of another species, would the cell structures change and adapt to the new DNA ...
3
votes
1answer
2k views

Pros/cons: linear vs. circular DNA [duplicate]

Why did Eukaryotes evolve to have linear DNA and not circular like Prokaryotes? What are the pros and/or cons?
1
vote
0answers
60 views

how to extract promoter regions given a TF binding site

I have constructed a PWM and want to test its accuracy. Scanning an entire chromosome (chr3, hg18) yields very high false positives (magnitudes higher than the true positives). Scanning the entire ...
7
votes
1answer
623 views

Is the six-layer cortex model of the mammalian cortex still the most accepted model?

I've been reading a bit about the different layers of the cerebral cortex and its clear that certainly not every region of the cortex has the same number of layers. Thus, the idea that every region ...
1
vote
0answers
44 views

If you are God, how would you create an efficient priming reaction? [closed]

Imagine that you are “natural selection” (or God if you prefer) and you can reconstitute replication changing the concentrations or the properties (higher/lower activity; reactivity; etc.) of the ...
3
votes
1answer
8k views

Do Penicillin based antibiotics affect birth control?

I wasn't sure whether to ask this question on Biology or Chemistry Stack Exchange, since it is really biochemisty, but this is something that's been puzzling me. Most pharmacists (all that I've ...
3
votes
1answer
116 views

IPTG and lac operator with e coli for foreign gene question

We did an experiment were we have e coli with a plasmid with a gene from another bacteria in it, and we put in IPTG in for induction. Will after looking up more about IPTG online I see it's related to ...
7
votes
2answers
195 views

A good textbook on GMO

I am interested in learning about GMO. The topic is so wrapped in controversy, that it's hard to find a good book that introduces the basic concepts involved. I went through various university ...
4
votes
1answer
103 views

How is the type of genetic manipulation determined in CRISPR-Cas9?

I've been reading up a bit on the CRISPR-Cas9 system for gene manipulation. From what I read, it introduces double-strand breaks at specific points determined by the choice of sgRNA. But how do you ...
6
votes
3answers
327 views

What is called the “area size that an animal usually lives in”?

What is called the "area size that an animal usually lives in" or "needs for a normal life"? Is there any specific term?
1
vote
3answers
217 views

Does the necessary Carbon Dioxide need to be in the atmosphere for mammals?

In the answers to this question, we've learnt that carbon dioxide is necessary for mammalian life, but is it necessary in the atmosphere/to breathe it in? Or does the act of respiration give a ...
5
votes
1answer
68 views

Total dark deprivation at day-neutral plants

First of all, I am not a biologist. Almost for a week, a question has come to my mind: "Is it harmful ceaselessly exposing a plant to light?" (I mean with natural & artificial light with ...
3
votes
1answer
48 views

What is an auditory upward sweep?

I was reading an article in nature communications, when I came across this sentence: "The ‘match’ rule was indicated by either a blue circle or a auditory upward sweep".So I tried googling what was an ...
8
votes
1answer
525 views

What is the difference between organelle membranes?

Cells and organelles are contained in lipid bilayers. I'm particularly interested in eukaryotic organelle bilayers and the biophysicochemical differences between them. Many papers assume a ...
1
vote
3answers
3k views

Why crossing over don't happen in mitosis?

I mean if there would be crossing over in mitosis then there would various nature of somatic cells. May be that's the logic,but what is the mechanism?why there is no crossing over in mitosis? Does ...
1
vote
2answers
45 views

Determination of a chemical compound in a non-homogeneous sample

This is a more generalized question of my other question here. I want to know if it is possible to determine a chemical compound in a non-homogeneous sample. I am asking this because we are aiming ...
0
votes
1answer
61 views

Core architecture of the body encoding [closed]

First of all, I am not a biology guy; I am in Computer Science. But, I have a strong interest in all the mysteries of nature, from universe to human body. So, I want to ask a question related to ...
0
votes
0answers
45 views

Is there a graph or ontology that maps diseases to its possible causes or causing diseases?

I am looking for a mapping, list, ontology or graph that shows the connection between a diseases and its (currently known) causes and/or risk factors. For example a well known risk factor for acute ...
3
votes
0answers
53 views

Human leukocytes (re)circulation/migration in homeostatic state

One can easily find information on the topic of leukocytes trafficking between vessels and peripheral tissues during inflammation. But what happens during normal states when there is no pathology? ...
1
vote
3answers
105 views

Can a portion of human skin cells be modified in some way to generate light? [closed]

I have come across some species of living organisms who are able to emit light at whim. Can that ability be incorporated into a portion of human skin (a specialized tissue)?
1
vote
0answers
2k views

Is a hard slap to the head a medical emergency? [closed]

I was just slapped in the head twice by my older brother (we had a fight). He hit me pretty hard with an open palm on the side of my skull, but I didn't feel dizzy or become unconscious. The stinging ...
3
votes
1answer
33 views

Authority on Microbiological Definitions

Is there an authority on definitions for molecular microbiology concepts, like an IUPAC book for chemical definitions? The particular definition I am debating is chromatin. Some say it encompasses ...
4
votes
2answers
252 views

Lyonization vs Genetic Imprinting

Lyonization is the process in which there is inactivation of an X chromosome in females. This process is implicated in mosaic forms of turner's syndrome (in this case the altered ...
1
vote
2answers
787 views

How does one calculate how to dilute a solution to working strength? [closed]

If I'm loading a 3.5ul PCR onto an agarose gel, how do I calculate how much of the 6x loading dye to add?
10
votes
5answers
1k views

Can the human brain be reduced to a binary system?

Does the brain really function like a computer as in, ultimately every response is related to a binary sequence based on whether particular neurons fire or not?
4
votes
1answer
199 views

Why is the upper respiratory tract so vulnerable to infections?

Wikipedia has the following statement on its Upper respiratory tract infection page: In United States URIs are the most common infectious illness in the general population. What is it about ...
4
votes
1answer
162 views

What happens to the umblical cord inside the mother?

After giving birth to a child, the umblical cord is cut (and stored if they want). The end connected to the child's navel will fell off eventually but what happens to the end inside the mother? Will ...
3
votes
1answer
198 views

How does Hemocytoblast constantly get formed into so many blood cells and yet remains there in the bone marrow throughout the lifetime?

I mean, Hemocytoblast is a stem cell which is constantly being differentiated into daughter cells and leads to formation of all the blood cells (having short and limited life spans), so how come those ...
9
votes
1answer
120 views

What species is this? Seashell from Indonesia

Anyone know exactly what species this is? I gather it may be an auger (family) or cerith (family) of some sort. This particular one is native to Indonesia's black beaches. Again: genus and species, ...
7
votes
2answers
195 views

Why are there no artificial wombs yet?

If the conditions within the womb are mimicked, and proper amniotic fluid with constantly recycling nutrients is maintained, is it not possible to obtain an artificial womb? Is there anything missing? ...
3
votes
2answers
82 views

Can genetically engineering the DNA of a human zygote, make it a twin of another human in entirety?

My question is simple. If I wanted to make an exact twin of an individual, will genetically engineering the DNA of the zygote to match with the individual suffice?
1
vote
0answers
27 views

How does so many replicas of different kinds of blood corpuscles form from different cells in the bone marrow? [closed]

I am interested in the process by which so many identical blood corpuscles form from an entirely different cell (within the bone marrow) altogether. How does these cells form?
3
votes
1answer
676 views

Can DNA & RNA be considered as nature's programming language?

The final frontier of Biological Sciences could be considered understanding the effects of variation in the DNA (and RNA). If after fertilization the DNA of the zygote could be genetically ...
15
votes
3answers
3k views

Superhuman eyesight

My ten year old son was reading car number plates that were too fast, too far away and at the wrong angle for any of us to read or even believe that it was possible for him to read. We thought he was ...
9
votes
2answers
150 views

Why can good music raise goosebumps?

Listening to really good music right now, I was wondering why it raises goosebumps. Is there any physiological reason for this reaction to specific wavelengths or something? EDIT: Due sometimes ...
1
vote
1answer
53 views

What is the expected number of children that need to be born for every possible point mutation to occur once? [closed]

I'm reading The Perfect Health Diet, and in it the author says that the probability of a point mutation is (175/3*10^9) per new child. He then goes on to write: In the Paleolithic, with 100000 ...
5
votes
1answer
16k views

Chromosome and chromatid numbers during cell cycle phases

A diploid cell in G1 has 6 chromosomes. How many chromosomes and how many chromatids are present in each of the following stages? Here is what I am guessing G1: 6 chromosomes ; 6 chromatids G2: 6 ...
7
votes
3answers
652 views

Do both ends of a muscle contract?

I was under the impression that both ends of a muscle contract. For instance, the fibers of the biceps run parallel to the humerus so I thought they pulled toward the middle. But now I'm confused ...
5
votes
1answer
688 views

How does a fetus retain a blood group different from its mother?

It's a well-established fact that blood group is decided by genotype. But, when a new child starts its journey in the womb, the mother's blood (along with it's agglutinins and agglutinogens) flows ...
7
votes
1answer
2k views

Why does a light object appear lighter in your peripheral vision when it's dark?

So, I am not sure I can reproduce it via images, but the steps are: 1) At night, open a window and have a look at the surface of the earth 2) Suppose there's an object that reflects a tiny amount of ...
3
votes
1answer
158 views

I found these skulls in a old bottle in the woods. Can you tell me what they are?

Can you help me identify these skulls I found in an old bottle in the woods?
8
votes
1answer
277 views

What creates the feeling of 'excess' blood pressure to an area of the body?

If I hang upside down, and feel blood rushing to my head, what structures are actually responsible for me "feeling" this excess flow of blood? Baroreceptors? Mechanoreceptors? Something else? ...
4
votes
2answers
2k views

What is biological dark matter?

I recently stumbled upon the Biological Dark Matter wiki page. Its pretty light on details, but it appears to be genetic material found in humans that doesn't fall into currently classifications. ...
2
votes
1answer
144 views

Do all sources supply all sinks on a plant?

Sources include any exporting organs, typically mature leaves, that are capable of producing photosynthete in excess of their own needs. Sinks include any nonphotosynthetic organs of the plant ...
2
votes
0answers
27 views

Why sudden stresses cause stuttering and/or other impairs in children?

The question is simple: Why sudden stresses cause stuttering and/or other temporary or permanent impairs in children (and even adults)?

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