3
votes
3answers
316 views

How do we look inside the cell?

My sister is in 9th grade biology and her teacher avoided answering the question of how we actually study the inside of a cell. I haven't taken biology in a while but I'd like to give her an answer. ...
1
vote
1answer
514 views

How to determine if this blood disorder is recessive or dominant?

This question is from "Concepts of Genetics," Klug & Cummings, 10e. "Thalassemia is an inherited anemic disorder in humans. Affected individuals exhibit either a minor anemia or a major anemia. ...
1
vote
1answer
209 views

Pituitary giants - is the fusing of growth plates dependent on amount of growth hormone in blood?

I wanted to ask a couple questions related to pituitary giants (people who are giants because of some anomaly, such as a tumor, in their pituitary gland). Some of these giants seem to keep growing ...
1
vote
1answer
94 views

What is the biological basis for tiredness after eating? [duplicate]

I can sometimes feel quite drowsy after some "meals" (e.g. a cold cut & cheese sandwich with juice on the side) and less drowsy (or maybe less often) after others (such as a salad). This ...
3
votes
0answers
230 views

How to prevent e coli from clumping (for FACS)?

I'm performing FACS on e coli, but the cells are clumping together so each event is multiple cells. I ran a control where I had one flask of e coli expressing GFP, and one flask expressing RFP. Run ...
1
vote
2answers
44 views

Why don't stem cell therapies use viruses?

Why don't stem cell therapies use a virus to deliver gene editing sequences to stem cells instead of the harvesting-transformation-transplant route. I thought it might be because of a lack of ...
5
votes
3answers
1k views

How does vasoconstriction/vasodilation change blood pressure?

Background: I am coming at this question from an electrical engineering background, and I feel like I am missing certain assumptions that are going into the statement found in my physiology textbook, "...
7
votes
1answer
115 views

What were the first neural systems like?

I'm curious about the origin of the neural network. I'm thinking perhaps once life evolved beyond the single cell organism, it needed a simple neural network to coordinate those cells, and cell ...
1
vote
0answers
107 views

Factors for sensitivity to electric shock

I'm frequently getting electric shocks in my office when touching things. I basically know why this happens and how to avoid it. Still I started to wonder what would be the best way to touch ...
2
votes
0answers
49 views

Death Psychology [closed]

Why do we sympathize in general when we see something or someone dying even if we personally don't know it/them? Is there any species which sympathize with the death of its own species? Is there any ...
0
votes
1answer
148 views

What shows how healthy someone is by their heart rate? [closed]

What shows how healthy someone is by their heart rate - how low it is at resting pulse or how low it is during exercise or how large the difference is between the resting rate and rate with load? Any ...
4
votes
1answer
310 views

If we change our breathing rate so easily, then what is the point of measuring it?

When we are self-conscious of our own breathing, its rate changes very easily. Therefore, if it changes so easily, what is the point in measuring it? Thank you for your time and effort
2
votes
2answers
2k views

Cell evolution: immortality vs reproduction

Many sci fi movies produce interesting ideas and technologies that we seem to be able to realize in real life at some point. "Lucy" was not one of those movies. But Morgan Freeman's speech in the ...
2
votes
1answer
96 views

What are the advantages of blood's redness? [closed]

Although this page (http://evolution.berkeley.edu/evosite/evo101/IIIE5aNotadaptation.shtml) denounces the idea that blood's redness is not an adaptation, I remain inquisitive on the matter since no ...
9
votes
1answer
3k views

why is DNA antiparallel? Can it be parallel?

My biology textbook mentions that DNA is antiparallel and it got me wondering... Can DNA be parallel? What would happen if it was parallel? could DNA still replicate right?
3
votes
1answer
101 views

Glycerol 3-phosphate nomenclature

Why is Glycerol 3-phosphate named in such way? Shouldn't it be named as Glycerol 1-phosphate by proper IUPAC- nomenclature?
1
vote
1answer
95 views

Which came first in hominid evolution: language or bipedalism? [closed]

I suspect both language-use and upright-posture have anatomical consequences. So does the fossil record show which came first? NOTE: To the folks who marked this question "homework": This is ...
3
votes
0answers
48 views

Why is ATP the main nucleoside triphosphate used to exchange energy? [duplicate]

Out of all of the nucleoside triphosphates what makes ATP the most used? Is it its structure? The amount of energy it contains? Why is GTP not used as much? What is the deal with the other nucleoside ...
2
votes
2answers
154 views

Parallels between pixelized image and the human retina

On Wikipedia it is explained that the human eye has a certain 'resolution'. Does this mean that the retinal image consists of pixels? If yes, what shape would these pixels have?
2
votes
1answer
93 views

In a typical population, what might the percentage of plants be to predators and everything inbetween?

I'm not sure if this will be a simple question that is almost a natural law for an ecologist, or a complex serious of assumptions. I vaguely remember from school that only 10% of the energy is ...
0
votes
0answers
83 views

Known ways to modify the genetic structure of the 13 loci used in CODIS

After reading the answer to Does our DNA change during our lives?, I was wondering if and how it would be possible to change the structure of the 13 loci that are used in the CODIS database, in such a ...
23
votes
1answer
7k views

Why do adults lose hearing at high frequencies?

Children and teens can hear high pitched sounds that adults can't hear anymore. Why do adults lose high-frequency hearing?
0
votes
2answers
1k views

Why is water a polar molecule? [closed]

Also, what is the definition of polar in this case? (9th Grade) Does it have to do with the bonds it makes?
1
vote
1answer
119 views

Multi-modal distribution for gene expression data

Why would some genes have more than two modes in their expression distribution? What external factors would cause this anomaly? I'm referring to the expression distribution of a gene across different ...
3
votes
1answer
238 views

how do macrophages have the capacity to digest pathogen in opsonization

how do macrophages have the capacity to digest pathogen in opsonization but not in the first time when the pathogen is new and they play the role of antigen presenting cells(APCs) first ...
7
votes
1answer
160 views

What is the mechanism by which lamins regulate gene expression?

The heterochromatin is generally localized at the nuclear periphery (also near nuclear lamina), whereas active genes are preferentially found in the nuclear interior. Children with Hutchinson-...
33
votes
3answers
23k views

Why draw blood from veins rather than arteries?

Why draw blood from veins rather than arteries? Is it more convenient or safer?
2
votes
1answer
59 views

How semi-synthetic cell with artificial DNA works

I know that by now this is old new but I heard that a cell that used a synthetic pair of nucleotides, called X and Y, have been made. My question was, how did the cell understand the X and Y ...
5
votes
3answers
1k views

How many different kinds of polypeptides, each composed of 12 amino acids, could be synthesized using the 20 common amino acids?

How many different kinds of polypeptides, each composed of 12 amino acids, could be synthesized using the 20 common amino acids? The book's answer is $20^{12}$. However, I disagree. This result ...
2
votes
2answers
270 views

Why asexual reproduction?

When I took a course on genetics and evolution, I learned that recombination and sexual reproduction is advantageous compared to asexual reproduction. Sexual reproduction allows more combinations of ...
1
vote
2answers
233 views

How does DNA damage cause ageing in yeast?

As I understand it, in yeast ageing there is daughter cell and mother cell. The daughter cell is has newly "fresh" DNA and mother cell dies after some counts of replication. What happens to the ...
3
votes
2answers
107 views

Energy metabolism in Cancer cells

The TCA cycle intermediate Isocitrate dehydrogenase commonly undergoes point mutations in cancers. This allows IDH to reduce a-Ketogluterate to 2Hydoxygluterate, causing a reduction in pVHLs ability ...
3
votes
1answer
439 views

What’s the reason for isovolumic contraction and isovolumic relaxation?

During cardiac cycle, there are two periods in which the heart volume doesn’t change, but there is a change in tension/pressure. It takes about 0.25-0.35 second to achieve this change. I searched in ...
1
vote
1answer
399 views

How do you call that part of the muscle that connects directly to the bone?

When you open up a chicken leg or a clam and you remove the meat, there is this little part that is connected to the bone and is not easily scraped off. What is this part called and what mechanism ...
0
votes
2answers
327 views

How to do whole genome sequence alignment in R or Ruby/C++, any good language? [closed]

I need to perform tuberculosis mutation analysis. First step I need to do is to align sequences in fasta format against one reference file. i tried CLC genomics workstation --- it hangs on 60 000 ...
5
votes
1answer
122 views

Is it dangerous to rub closed eyes?

Phosphene from rubbing the closed eyes where first described at least since Ancient Greece, but I caught myself thinking that I wouldn't want to try it out. So I wonder, how safe it is to actually rub ...
3
votes
0answers
24 views

Inter-codon mutations statistical analysis

I am looking for a statistical approach to inter-codon mutations. For example a 64*64 (64*63 actually) table, that contain the possibility of mutation from one codon to another codon (CCA to CAA or ...
1
vote
0answers
26 views

Why after physical activity I see flickering concentric circles? [duplicate]

After prolonged hard physical exercise such as running uphill I sometimes experience rapidly vibrating black-and-white concentric circles for a few minutes, looking like a sinusoidal zone plate, small ...
2
votes
1answer
61 views

Is it possible that a set of functionally related proteins in a pathway fulfill different functions? [closed]

Could it be that a given pathway of enzymes (or proteins in general) may fulfill different purposes in a cell by for shifting partners? Say protein A activates B, B activates C and C has a specific ...
4
votes
1answer
135 views

What effects does being cryogenically frozen have on a person's body? [closed]

I'm wondering what effects are known to happen to a person's cells when a person is cryogenically frozen, especially those that need to be overcome in order to "bring them back to life." From a ...
0
votes
1answer
59 views

Does the size or mass of a body affect the time it takes for rigor mortis to sets in?

Does the size or mass of a body affect the time it takes for rigor mortis to sets in? For example: compare a 300 pound man to 100 pound girl to 5 pound animal.
11
votes
1answer
991 views

Grapefruits and CYP3A4

Grapefruit juice contains furanocoumarins, which irreversibly inhibit CYP3A4. For this reason, when one is taking certain medications it is necessary to not eat grapefruits because the inhibition of ...
0
votes
1answer
77 views

How much of the human body is processed sunlight?

So I believe (and correct me if I'm wrong--it's logic, not research) that the human body is pretty much all just processed sunlight based on the food chain. How much, if any, of the human body is ...
4
votes
0answers
68 views

Are there any viruses that have infected all humans in the past or present? [closed]

Are there any known viruses that have managed to infect all of humankind either in the past or presently, either benign or otherwise?
0
votes
0answers
43 views

Are there any viruses that are part of all land animals?

An article on I Fucking Love Science (linked to below) got me thinking, are there any viruses that have been so successful that they have spread to all land animals similar to Toxoplasmosis which has ...
1
vote
2answers
560 views

What does to “evolve” exactly mean? [closed]

In this article, the author says: Evolution isn’t “leading up” to anything, it just drunkenly limps along using the same set of tricks in slightly different orders. On other occasions, however, ...
3
votes
1answer
330 views

What does x in “Miscanthus × giganteus” name stand for?

I came across a species name that contains "x" in its name, namely Miscanthus × giganteus. What does this symbol stand for and is it commonly used in taxonomic nomenclature?
0
votes
1answer
444 views

Is it true that some organs “sleep” at certain times of the day and does this affect dieting or when to take medicine?

Is it true that some organs (such as the liver or the intestines) are less active at certain times of the day, regardless of whether the individual is awake or not?
2
votes
1answer
942 views

Which Papaya (Lechosa) plant (male or female) bears fruit?

I will be planting Papaya fruit seeds and I understand that there is a female and a male plant, so how can one distinguish which are the ones that will bear fruit and which I should just rip up by its ...
12
votes
3answers
2k views

Does a man contain all the genes needed to make a woman?

This question is brought on by a Sci Fi novel I am thinking about writing. The plot device involves a colonist in charge of building a population on a new planet who loses his supply of embryos and so ...

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