The study of cells, their physiological properties, structure, environmental interaction, division, life cycle, and death, as well as the organelles they contain. Also known as cytology.

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58 views

How difficult is it to make a shRNA/miRNA/siRNA to silence/knockdown NaV1.7 voltage gated sodium channels in humans?

There have been various research projects that experimented with shRNA/miRNA/siRNA to specifically silence/knockdown NaV1.7 voltage gated sodium channels in small animals like rats & guinea pigs. ...
4
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1answer
50 views

Is HSV-vector-mediated miRNA expression in dorsal root ganglia stable?

My question is on the following article: "Reduction of voltage gated sodium channel protein in DRG by vector mediated miRNA reduces pain in rats with painful diabetic neuropathy" My question is, do ...
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2answers
240 views

At any given moment, how much energy is stored in the human body as ATP?

At any given moment, approximately how much energy is stored in the human body as ATP in the ADP-P-bond? This of course depends on what type of cell it is and the activity of the individual in ...
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1answer
40 views

What is the purpose of requiring two separate binding systems for the antibody response?

I've read that in most cases, B-cell activation requires helper T-cells. This requires antigen binding by both antibodies and T-cell receptors, using two different antigen-binding proteins, ...
4
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1answer
55 views

How was gene therapy able to cure diseases through the transformation of actively dividing cells?

I thought that gene therapy, when performed on target cells that regenerate themselves constantly, can be effective for a limited time only. I.e., the effect gradually wears off after a while, ...
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2answers
47 views

At which end does polymerization of microtubules occur?

My book says that polymerization and depolumerization of microtubules occurs on the + end however, I've found a note that says that depolymerization occurs on the - end. I need help please :) thank ...
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0answers
26 views

Effects of pH vs membrane potential within a cell? [closed]

How are these two concepts related? Does changing each result in the same effects? As in: what kind of reactions/processes would be affected if we changed the pH within a cell? Would the results ...
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2answers
82 views

In cell division, are daughter cells identical?

I understand that after a cell replicates, there will be two daughter cells instead of one. But wouldn't one of them be the old cell that created the second one? The old cell having gone through G0, ...
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1answer
31 views

Constant or variable number of chiasmata during recombination?

During recombination, is the number of chiasmata consistent for each gamete and are the chiasmata regions consistent within a single organism?
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1answer
162 views

Do human somatic cells have 46 chromosomes all the time?

As far as I know, a human somatic cell has the cell cycle: Interphase and Replication (mitosis). In interphase the cell has 2 growth phases (G1 + G2) and a synthesis one (S phase being in between G1 ...
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18 views

How sorbitol treatment selects ring stage of plasmodium falciparum

I would like to know the basic chemistry behind ring stage selection by sorbitol. Sorbitol is used for Synchronising the plasmodium culture in ring stage. How the chemical retains or selects ring ...
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2answers
175 views

Do chromosomes uncoil in interphase II?

During interphase II, there is no S phase in which DNA replicates. However, in this stage, do the chromosomes remain wound? Or have they unwound into chromatin form, and recondense during prophase II? ...
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1answer
46 views

cell specialisation and their location

When we create new cells, how come they are of the 'right' type at the 'right' place? For example, when I make a new cell on my lips, it's obviously not the same as a new one in my kidneys. Is the ...
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1answer
54 views

Are nucleotides at the ends of DNA stripped on aging?

I had the following understanding (now after reading a popular science article seeming wrong understanding): DNA in (regular) cells (in human and some other organisms) are protected by telomers. ...
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0answers
17 views

Ions in different cell compartments

I would like to understand the distribution of metal ion concentrations (such as Mg2+) in the different cell compartments. I tried very hard but still couldn't find such information. Could anyone ...
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1answer
61 views

Which steps occur in each phase of Meiosis and Mitosis [closed]

MITOSIS In mitosis am I correct in saying that the spindles attach to the centromeres at the end of prophase/prometaphase? (I read this in an answer to another question) MEIOSIS Does the ...
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1answer
48 views

Why only mitochondria and plastids?

Why are there only two unique semi-independent organelles? Why are there no others, symbiogenesis seems like it should be a relatively common thing. So do most organelles just lose all their DNA? Or ...
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1answer
103 views

In the video, “Inner Life of a Cell”, what's the empty space between the molecules?

In the video, "Inner Life of a Cell" there's a lot of empty space between the proteins. Is it just a simplification (i.e. they omit smaller molecules)? If so, what are the smaller molecules supposed ...
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1answer
36 views

How chameleons change color? [closed]

Well, I was watching a video about chameleons and I saw that their cells can change color. Can someone explain me how is this possible?
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1answer
85 views

What determines whether the maternal or paternal allele is expressed?

I am taking cell biology and have this question: During the process of gene expression, it is possible to express either the maternal allele or the paternal allele. When and how is the determination ...
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1answer
62 views

What are allogametes? please explain [closed]

Allo means different or unrelated I guess.Please clear me the meaning with some examples.
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1answer
75 views

Are surface area or volume conserved during cell division?

I am a student of physics of mathematics with very little knowledge of biology. Nevertheless, I am very keen on biophysics and I'm trying to learn the biological concepts that I need on the way. I'm ...
2
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1answer
652 views

Difference between protein channels, protein carriers and protein pumps?

I'm revising for my biology exam and I don't fully comprehend the difference between protein channels, carriers and pumps. I know that: Protein channels do not require ATP (passive transport) The ...
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0answers
24 views

Degenerate primer designing software

Can any one provide online free degenerate primer designing software. I have tried couple of them like CODEHOP is one where BLOCK formatting step finding difficulty, can anyone help me out....
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1answer
70 views

Reseach on feeling pain of other people

I'm more of a tech than bio kind of guy, but I have read and learned a lot alongside of my girlfriend's education. Which is very interesting!! Currently I want to investigate : people claiming to ...
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1answer
34 views

Where exactly is 'Colloid' with regards to synthesis of thyroid hormones?

I've researched colloid and it seems to be a substance of microfibres and thin films in which thyroid hormones may be synthesised, but I was wondering where this exactly is... I think it could be in ...
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1answer
44 views

Lysosome function [closed]

Does any cell have lysosomes in it? Or maybe there are other organelles that do the same function. I read about it a lot and I can't find a good answer.
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0answers
35 views

How do cell repair mechanism ratios change as they age?

I have seen that embryonic stem cells are shown to use homologous repair for double strand breaks rather then non-homologous end joining (NHEJ). [1] I am wondering if something also happens to a ...
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2answers
448 views

Mitosis versus Meiosis I: What's the difference?

At the end of mitosis, one cell has divided into two diploid cells. But at the end of meiosis I, there are two haploid cells. How are the two processes different to produce these two types of cells?
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1answer
222 views

Reason for the source of fetal bovine serum

What is the reason that perhaps the most commonly used serum in labs is fetal bovine derived? Is there something about fetal serum that is particularly useful over say serum just harvested ...
3
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0answers
57 views

Is it possible to isolate cells harboring a specific DNA sequence?

Suppose on cell subpopulation harbours within its genome a specific DNA sequence that do not exist in other cell subpopulations. Is it technically possible to isolate such subpopulation ? and if yes, ...
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1answer
49 views

Cellulose - why is it fibrous and not granular?

I was reading a book where it said that the 1 - 4 Glycosidic bond of the Beta Glucose meant that cellulose is fibrous and not ...
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1answer
53 views

Which organs need to have fluid compartments in order to develop properly?

I am a student, slightly struggling with the new concept of fluid compartments. I know that there are two main types of fluid compartment, extra and intracellular fluid. I also read that most organs ...
2
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1answer
110 views

How does the pancreatic beta-cell know how much insulin to secrete in response to glucose?

How do $\ce\beta$-cells know how much glucose is in the blood? I know that when glucose enters a beta cell it triggers the cell to produce insulin. $\ce\beta$-cells trap glucose by converting it into ...
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1answer
34 views

What effect is seen when the extracellular concentration of sodium is increased? [closed]

I can't seem to figure out how this would effect the cell since sodium is not very permeable.
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18 views

Amputation of part of the cytoplasm of the amoeba? [closed]

We ampute a part of the cytoplasm of the amoeba many times and we observe that amoeba is not divided This experience allows to deduce the cause of the division of amoeba Do that have relation with ...
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1answer
124 views

Is a nucleus more dense than the rest of the cell?

On the one hand, it seems like there's a higher density of 'stuff' in a nucleus, so it should be more dense. On the other hand, if it was more dense, I'd imagine that nuclei would 'settle' to the ...
7
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1answer
128 views

If so many different hormones/molecules work by activating adenylyl cyclase, how do they have different effects?

It seems that many hormones and molecules work by activating adenylyl cyclase to convert $\text{ATP}$ to $\text{cAMP}$, such as adrenaline and glucagon. Both of these seem to bind to $\text G$ protein ...
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1answer
65 views

Hayflick limit and hair or nails

I am not a bio major but I have heard about Telomerese shortening in each cell division which leads aging and cellular death. I also read that Hayflick limit is about the number of divisions a cell ...
0
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1answer
39 views

How DNA programs the first cell in womb into a human [closed]

Sorry if you see me silly. I am just a programmer happens to be curious about biology... So far I understand how DNA make protein, how cell divides, how one composed of cells->tissues-> organs. ...
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0answers
24 views

Pathogenesis of type IV hypersensitivity

In hypersensitivity, as I understand it, a normal immune response gets excessive, misdirected or wrongly regulated to cause tissue injury. The various types determine the various ways in which the ...
2
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1answer
75 views

Is the problem of cryonics only the pressure?

According to the pop-sci sources which I drew on from, the only problem with freezing whole bodies its that you can't conserve it without freeze-damage. If you were keeping a cold-blooded animal in a ...
2
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1answer
66 views

Are there differences in energy of glucose isomers?

There are many isomers of glucose, including galactose and fructose. Do they have different chemical energy levels, and why? What makes galactose and fructose useful compared to glucose, and would ...
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0answers
23 views

Could drugs promoting angiogenesis be used as a treatment for burn victims?

From what I've learned from my textbooks and in class lecutures it seems that inducing angiogenesis for people with severe burns would be an excellent way to speed up the healing process. Is this ...
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1answer
42 views

Why is Bcl2 a good target for cancer therapy?

Bcl2 is a family of proteins that are involved in the inhibition of apoptosis in cells. My question is that what makes this anti-apoptotic protein useful in cancer therapies as opposed to focusing on ...
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1answer
33 views

why dna polymerase 3 requires a primer for replication [duplicate]

Why DNA polymerase 3 needs a primer to star replication.And whats happens when there is no AUG sequence on entire DNA.
2
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1answer
34 views

How are cardiac cells stimulated by an action potential?

Why, and how, does the action potential of one cell in the heart stimulate an action potential in the next cell? I'm interested in an answer with citation.
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0answers
17 views

Arginine finger for regulating GTPase activity of heterotrimeric G-proteins as well?

I've seen video on iBiology discussing mechanism of Ras-Gap protein regulation of Ras protein (monomeric G-protein) involving an "arginine finger' from Ras-Gap for stabilization of intermediate in ...
3
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1answer
47 views

Why does a cell produce a lot of p53 protein only to later degrade it?

It is known that the half life of p53 is short and so does that play a role in the amount of energy the cell would need to expend to degrade all the p53? By that does the fact that the half life of ...
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31 views

Why don't the minus ends of microtubules shrink?

Is this because $\alpha$-tubulin is always in the GTP state? Or is it because $\gamma$-TuRC stabilizes the minus end?