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.

learn more… | top users | synonyms

5
votes
1answer
137 views

Cell proliferation limit and senescence of embryonic stem cells and fibroblasts

I am trying to understand the importance of proliferation limits and cell senescence. In particular, I would like to compare the proliferation limit of Embryonic Stem cells (ES) and fibroblasts (which ...
6
votes
1answer
239 views

Computational/mathematical models for predicting phenotype from genotype

Karr, Sanghvi, et al. (2012) propose a whole-cell computational model for predicting phenotype from genotype in Mycoplasma genitalium. Their model simulates myriad cell processes such as DNA ...
4
votes
1answer
306 views

Lifespan of connective tissue cells

This post is regarding a follow up on my initial post on "Properties and life cycle of chondrocytes and tenocytes". I am elaborating on my question on the lifespan of tenocytes and chondrocytes. ...
6
votes
2answers
130 views

Intrinsic apoptosis in erythrocytes

With a lack of mitochondria, can red blood cells perform intrinsic apoptosis and do they have another way of generating cytochrome c to attach to a CARD domain and assemble the apoptosome? Or are ...
1
vote
0answers
84 views

Properties and life cycle of chondrocytes and tenocytes

Questions regarding chondrocytes and tenocytes: Do these cells replicate, or are they regenerated from mature stem cells? How often are these cells regenerated? How long do they live? Do they ...
3
votes
1answer
399 views

Is collagen supplementation useless?

When collagen is digested is it broken up into usable components that the body can use to produce its own collagen? What evidence is there that supplementing with collagen type I & II etc.. can ...
6
votes
2answers
6k views

How do archaea relate to eukaryotes and bacteria?

I've read that they all share some genes, internal structure, and behaviour with each other, but with different degrees of overlap depending of what the function is. E.g., archaea have some eukaryotic ...
1
vote
1answer
33 views

Where can I find a transcriptome of a normal uveal melanocyte?

I am looking for a database where I could find a transcriptome (say obtained with a microarray analysis) of one (or ideally many) normal uveal melanocytes ?
5
votes
1answer
88 views

Significance of basal lamina for outer layers of epithelium

In stratified (not pseudostratified) epithelia such as the epidermis, what purpose does the basal lamina serve for the outer layer cells which do not even stand in contact with it? Also, how do these ...
7
votes
1answer
255 views

How fast do different organs turn over cells?

It is said that the human body turns over all cells or molecules in 7 year cycles. This is not quite correct, because there are different organs changing at different speeds. My interest is what is ...
4
votes
1answer
119 views

Regarding TIMP and MMP enzymes

Are there substances that can promote TIMP enzyme production, or MMP enzyme production or supression in tendons? Are there medical tests that measure quantities of MMP and TIMP enzymes in tendons?
4
votes
0answers
57 views

Can NSAIDs impact negatively the healing of tendons?

There are a number of articles regarding NSAIDs having a negative effect on healing conditions like tendonosis and tendinitis. From what I understand the channel through which they reduce inflammation ...
5
votes
1answer
490 views

Is there a relationship between efficiency of cellular metabolism and warm-blooded-ness?

My BIO 101 book states that when human cells convert glucose to ATP, the process is only approx 35% efficient, and much of the potential energy is lost as heat. However, that heat is useful to us in ...
5
votes
1answer
124 views

Which cells are responsible for the extracellular matrix remodeling?

I am studying a case of tendinopathies induced by an alteration of how the extracellular matrix is being remodeled. From my understanding there has to be a careful balance of MMP (metallproteinases) ...
6
votes
1answer
289 views

Are the cytosol and extracellular fluids electrically neutral?

I've found several sources that state that overall, the cytosol of a cell is electrically neutral. The extracellular fluid is also purportedly electrically neutral. How can that be when we have ...
3
votes
0answers
23 views

What metabolically happens when an egg fuses with the nucleus of a somatic cell

In stem cell biology, it is recognized that embryonic stem cells are transcriptionally inactive for the first 3 days of development. However, during somatic cell nuclear transfer, the nucleus is ...
6
votes
2answers
70 views

Macrophage pathogen fixation

Overly simplified, macrophages recognise pathogenic patterns and endocytose anything that matches them. That also works on bacteria, which are quite often very mobile. What if a bacterium was just ...
10
votes
1answer
1k views

Is the eukaryotic nucleus composed of a single or double membrane?

I know that it is usually considered a double membrane like those surrounding mitochondria and chloroplasts, but I read a review that stated "according to topological details it is actually a single ...
10
votes
1answer
10k views

How to store vegetables in the refrigerator: In plastic bags or not?

My wife and I are having a debate similar to this one: I claim that it's better to take the fresh veggies out of the bags and put them in the crisper with humidity control because: That's what the ...
6
votes
1answer
257 views

How similar are Circulating Tumor Cells and Cancer Stem Cells?

Circulating Tumor Cells (CTCs) are linked with metastasis and their presence can be used to indicate the onset of metastatic cancer. Likewise, the Cancer Stem Cell (CSC) hypothesis suggests that ...
7
votes
1answer
70 views

How do nuclear receptors locate each other to form a DNA loop?

Nuclear receptors can influence transcription far up- or downstream from their own binding sites by looping DNA (Rubina et al.; J Mol Bio 2004). I am not sure how exactly the receptors first attach ...
10
votes
2answers
441 views

Could hydrogen replace oxygen in cellular respiration?

I was wondering what oxygen actually does in the body. I have seen a few answers to other questions that involve the electron chain and I am really not sure what that is. So I was wondering what ...
6
votes
1answer
78 views

number of RNA pol II molecules in a given human nucleus?

Does anybody have any estimate on the number of RNA pol II molecules in the nucleus of a given human cell? For example, how many RNA polymerase type II protein complexes would there be on average at a ...
2
votes
1answer
56 views

Measuring the density of surface antigens

I'm trying to get a sense of the variety of methods used for determining the number of cell surface antigens and receptors. This is notably different from determining the affinity of these surface ...
5
votes
2answers
88 views

How extensive is CD47?

CD47 aka the "don't eat me" signal has recently been claimed to be expressed on all tumor cells. This doesn't seem to corroborate with other cell-biology experiments. On what other cells is CD47 ...
11
votes
1answer
89 views

Does a theory exist for the formation of thylakoid structure?

I'm interested in how the structure of the thylakoid forms into its characteristic highly rugose stacks of grana. What causes the thylakoid to invaginate and self-associate, albeit with what appear to ...
5
votes
4answers
3k views

RNA or ribosome, which one moves during translation?

During translation ribosomes decode the genetic information present in the mRNA and protein synthesis takes place. During this process which of those two does move, the ribosome or the mRNA?
7
votes
1answer
182 views

When collecting cell lysates for a Western blot, how do I induce di-sulfide bonds?

I would like to conduct a simple dimerization experiment for some protein I'm collecting from a cultured cells. My thought is, that if I'm running a non-reducing, denaturing PAGE gel, then removing ...
5
votes
2answers
89 views

Synthetic biology using existing cells

I was watching the video at this link: http://www.bbc.co.uk/news/science-environment-17436365 The speaker says that a cell is taken and its original DNA content is stripped out and replaced with ...
8
votes
1answer
420 views

What is a inhibitory tone when talking about neurons?

In this SE answer: Could an "overactive" brain increase the chances of Alzheimer's Disease? user @nico used the word inhibitory tone What does that ...
7
votes
1answer
5k views

What is the difference between “dikaryotic” and “heterokaryotic” states in the sexual lifecyles of fungi?

Many fungi undergo a reproductive phase in which more than one genetically distinct nuclei (from 2 separate mating types) is present within the same cytoplasm. In the Ascomycota and Basidiomycota, ...
22
votes
1answer
315 views

How does a cell know its size?

Cells come in all sorts of sizes. How do they regulate their cell size to the point where similar cell types have a fairly mono-disperse size distribution? Reasked from ...
8
votes
1answer
384 views

Do larger multicellular organisms have an increased risk of mutation and thus cancer?

So I was thinking that if each cell has P(X) of becoming cancerous, then the chance of cancer is 1-((1-P(X))^n) where n is the number of cells in the organism. Since larger organisms have more cells ...
4
votes
1answer
300 views

What's the distinction between a tetrad and a synaptonemal complex in meiosis?

What's the distinction between a tetrad and a synaptonemal complex in meiosis? Are they synonyms? I ask because the concepts seem very closely related, but it seems like there may be a subtle ...
6
votes
0answers
64 views

Pancretic Acinar Cell - ATP, calcium concentration data

I need to find a decent source of data for concentration of ATP and calcium in the pancreatic acinar cell. So far all I can find is ATP or calcium 'levels' based on fluorescence , which are not ...
17
votes
3answers
202 views

How crowded is the bacterial cell?

I was wondering what is the protein concentration in an E. coli cell. When studying enzyme kinetics and activity in vitro, I would argue that the substrate and enzyme concentrations resemble those in ...
8
votes
1answer
249 views

How is the number of mitochondria in a cell regulated?

How does the cell regulate the number of mitochondria in a cell? What happens when there are too many or too few?
6
votes
2answers
604 views

What is the main general difference between Mitosis and Meiosis?

I found such a clause: The general principle is that mitosis creates somatic cells and meiosis creates germ cells. However, I cannot agree. Each gametogonium needs to go through mitosis before ...
10
votes
1answer
368 views

Does electricity cause damage on a cellular level?

As I understand it the mechanism of death when a mammal is electrocuted is that the current disrupts the SAN/AVN in the heart causing it to fibrilate or arrest. That's on a macro scale, however. ...
6
votes
1answer
156 views

What's a good reference for choosing histological staining chemicals?

It's often difficult to find the appropriate or best stain to use when I want to examine a new type of tissue. I think that's partly because many histological techniques were developed a long time ...
5
votes
1answer
610 views

How does water buffer a sudden drop in temperature?

A property of water is that it is slow to heat and cool. According to my biology book, some energy from an increase in temperature would spent breaking hydrogen bonds, so that temperature does not ...
22
votes
1answer
479 views

How long will a vegetable live for after being harvested?

I understand this might depend on the types of vegetables, but is there an average or studied specifics? Does it die immediately? Is there a way to precisely diagnose death in plants? If so, what are ...
6
votes
1answer
65 views

How are chromatids correctly segregated during mitosis?

In my book this is described as happening by kinetochores depolymerising from their attached microtubule spindle, then being dragged towards the spindle's centrosome by a dynein protein. I can ...
11
votes
1answer
471 views

Did researchers evolve multicellular yeast or did they just turn on multicellularity?

In this new paper "Experimental evolution of multicellularity" found via Ars Technica the researchers describe having developed multicellularity and apoptosis within 60 days from a unicellular yeast ...
8
votes
3answers
400 views

What triggers meiosis in gonadal cells?

What specific biochemical processes are involved in inducing meiosis rather than mitosis? Why are gonadal cells the only cells in the human body which do undergo meiosis?
5
votes
1answer
935 views

How does the Golgi Apparatus perform its function?

The Golgi Apparatus is an organelle with a great number of functions, I am particularly intrigued in the role it plays in packaging macromolecules and sending them to their target organelle or to ...
7
votes
2answers
194 views

Is “exhaustion” of the Hodgkin-Huxley membrane at constant stimulation a real phenomenon?

I was playing around with a simulation of the Hodgkin-Huxley model using their original parameters for the squid giant axon. By applying a constant stimulation current to the model in resting state, ...
14
votes
6answers
789 views

Online Molecular and Cellular Biology Video Lectures?

I am looking for video lectures to go through to guide my reading in intro molecular and cellular biology. I've had intro bio and I study evolutionary theory, but my molecule- and cell-level knowledge ...
6
votes
1answer
161 views

How Do Large Ocean Viruses Form Their Own Organelles?

Several large viruses (Arslan 2011) form their own organelles within the amoebae they invade. How do these organelles form? Reference: Arslan, D., Legendre, M., Seltzer, V., Abergel, C., Claverie, ...
19
votes
1answer
502 views

Are lymphocyte sizes clustered in two groups?

Tortora writes in Principles of Anatomy and Physiology: Lymphocytes may be as small as 6–9 μm in diameter or as large as 10–14 μm in diameter. Those ranges are quite close to each others. Should ...