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

2
votes
1answer
22 views

Detailed mechanism of the cause of diabetes mellitus type 1?

I have read in some texts that diabetes mellitus type 1 is caused by degeneration of beta cells due to our body's own immune reaction.Is it true? Can you explain further how are such types of immune ...
11
votes
1answer
15k 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 ...
0
votes
1answer
21 views

How did multicellular life evolve? [duplicate]

I can imagine several specialized unicellular beings collaborating. But how does life get from that point to a unique pluricelular being that reproduces into another pluricelular being?
1
vote
2answers
152 views

Can cell exist without Ribosomes? [on hold]

Last night I came across a question that goes as follows:- Cells cannot exist without a) cell wall b) cell membrane c) mitochondria d) ribosomes I am getting confused with option B and option D ...
-2
votes
0answers
20 views

How robust are immortalized cell lines? [on hold]

I was listening to this story by Radiolab where they mention that HeLa cells contaminate other cell cultures and can float on specks of dust. Wikipedia says that HeLa cells are robust. My question is ...
4
votes
0answers
36 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 ...
4
votes
1answer
35 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 ...
0
votes
2answers
433 views

Why do living organisms replicate itself or procreate

Why do living organisms spontaneously replicate itself or "procreate" (my understanding is that it does). From a uni-cellular and micro-organism point of view. Is there some sort of stimulant in the ...
5
votes
3answers
49 views

What advantage does an enzyme serve over catalysis by the addition of heat energy?

I understand that an enzyme lowers the activation energy, allowing the reaction to run faster, however I am not sure, how it may be favorable during the addition of heat energy. Wouldn't that lower ...
1
vote
1answer
35 views

What is the present tense verb form of apoptosis?

For example, if I want to say something along the lines of "this signaling pathway causes a cell to go through the process of apoptosis", but I want to shorten the phrase "go through the process of ...
6
votes
1answer
57 views

What allows Valonia ventricosa cells to get so big?

Valonia ventricosa are single celled algae that range between one and few centimeters. In rare cases they can reach sizes exceeding 5cm. Weirdly, a lot of the literature covering these organisms ...
2
votes
0answers
24 views

Expression/Mechanism of ROR1 in healthy tissue

ROR1 is currently under investigation as a therapeutic target for cancer (1). A number of studies show different cancers may have their metastatic potential reduced, or become apoptotic through ...
1
vote
1answer
31 views

What is Trypsin? [closed]

I am currently helping a PhD student in his research lab. We have been using Trypsin for the past couple of weeks but I am unsure of its purpose. I was wondering how Trypsin functioned and what it was ...
3
votes
1answer
64 views

What are senescent cells doing in our bodies? [closed]

I'm reading a paper that mentioned the elimination of senescent cells delays aging. I'd like to receive more information about it. The Baker study published in Nature demonstrates that targeted ...
0
votes
1answer
35 views

Why does the cloning scheme to shuttle GFP into a pL4440 have to be between two T7 promoter regions? [on hold]

When designing a cloning scheme, why does it have to be between the two T7 promoter regions, and what is the benefit of using one or two enzymes to perform this?
1
vote
1answer
35 views
6
votes
1answer
36 views

What is a positive epitope fragment

What is a positive epitope fragment? I found one paper on the subject: COBEpro: a novel system for predicting continuous B-cell epitopes by Michael J. Sweredoski and Pierre Baldi
2
votes
0answers
34 views

How long can a human neuron cell live outside the body in a controlled environment?

Have there any experiments been to keep neurons alive (stationary) without preserving methods such as freezing? If yes, for how long?
4
votes
1answer
20 views

Can methylation of a promoter induce gene expression in some rare cases?

Can methylation of a promoter induce gene expression in some rare cases? I've read somewhere that methylation of an intron can induce gene expression (eg. Igf2). How is that even possible? Thank ...
3
votes
1answer
106 views

Which of the two mitochondorial membranes relate to bacteria according to the endosymbiotic theory?

I seached for endosymbiotic theory in Wiki and I found this about endosymbiotic theory: Symbiogenesis, or endosymbiotic theory, is an evolutionary theory which explains the origin of eukaryotic ...
3
votes
3answers
53 views

why do some cells in the body prefer necrosis to apoptosis as a means of cell death?

There are many programmed cell death pathways, but some cells show a greater preference for some over the other. I'm wondering as to why if necrosis is an inflammatory response that causes damage to ...
6
votes
2answers
381 views

What are the differences between cancer and tumour?

What are the differences between cancer and tumour? I mean is it in the DNA or shape or something else... And how can a benign tumour turn into a malignant tumour? The body has a lot of tumours all ...
4
votes
1answer
76 views

Trying to differentiate between the three muscle tissues with small pictures

For an assignment I have to differentiate the three types of muscle tissues in these three pictures . I'm having difficulty seeing the striations and branches etc. because the pictures are so small. ...
1
vote
1answer
19 views

Why does a tumour's genome change depending on the environment?

According to the book "Primer of The Molecular Biology of Cancer" by Vincent, Theodore and Ateven, the tumour cell is changed depending on its environment. performed genome-wide analysis on three ...
4
votes
1answer
172 views

Is this a grass cell?

I found this picture online claiming it was a grass cell. Clearly it is a cross section image but I was hoping you could tell me if this is actually grass, or something else if anything. Thanks!
2
votes
0answers
21 views

What has to duplicate before cell enters M phase?

What has to duplicate before cell enters M phase? DNA histones centrosome mitochondria (any other organelles?) condensins (not sure?) have I forgotten anything? Thank you in advance!
3
votes
3answers
264 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. ...
3
votes
0answers
43 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 ...
2
votes
0answers
43 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 ...
0
votes
2answers
95 views

What triggers programmed cell death in humans (from outside the cell)?

What triggers programmed cell death in humans? Is it decided by the brain (for the entire body)? Or is it a local decision of a cell by its environment? Something else? I realize that there might be ...
3
votes
0answers
35 views

Why is heterochromatin localized next to nuclear lamina?

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 ...
1
vote
0answers
30 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
54 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 ...
9
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 ...
0
votes
1answer
37 views

Immunomic Microarray

"One can measure two or more signals simultaneously determined by a single feature, i.e., epitope in immunomic microarray DNA microarrays measure one response value for each gene per sample; that ...
0
votes
1answer
31 views

Why do some cells like myofibrils have multiple nuclei?

I see that myofibrils (muscle cells) contain not one, but multiple nuclei. Why is this so? Do all the nuclei participate in cell division?
3
votes
1answer
29 views

Estimating RPM to RCF in Methods from Older Papers

I'm attempting to replicate a cell biology method from a 1958 Laboratory Investigation paper. The protocol is for the isolation of an extracellular matrix protein, and a key step is a centrifugation ...
8
votes
1answer
189 views

Single long axon vs serial neurons

Based on the comments in this post and also this chat. For discussions and speculations please comment in the chat. The basic question is what is the advantage of having a single long axon such as ...
5
votes
2answers
658 views

How fast do cancer cells divide, compared to normal cells?

This question suggests that we have, on average, 50-70 billion cell divisions per day. I just read that cancer cells divide more often and are therefore more prone to radiation. I am wondering, for ...
4
votes
1answer
105 views

When should endocytosis inhibitors be used in cell binding assays?

I'm beginning to do some cell-binding assays and I would like for my proteins to not be endocytosed by my mammalian cells. Typical suggestions are for the cells to be kept on ice and that the binding ...
3
votes
1answer
42 views

Prevent biofilm formation on moist surfaces

I have an indoor fountain with lots of water. What are the most common microorganisms in this kind of moist environment, and what are the standard way to prevent biofilm formation by them? I thought ...
2
votes
2answers
55 views

Does the cellular response to every receptor work the same way?

I heard somewhere that activating any receptor results in the same intracellular response (signaling) which involves NF-κB. If that is true, I hardly understand how the cells distinguish between ...
7
votes
1answer
404 views

Are pulp cells (in oranges) normal plant cells?

Does a pulp cell contain all the elements that a 'normal' plant cell contains? I've searched for an hour to find more information about this but couldn't find anything useful. Is the pulp cell the ...
0
votes
1answer
63 views

What is the second phase of photosynthesis?

I really want to know what the second phase of photosynthesis (in the dark) is. I have a fair understanding of the first cycle where molecular oxygen is generated under the influence of light, but I ...
4
votes
2answers
113 views

Can I force evolution in a group of cells by removing all the smaller cells?

I actually have algae growing in water in a container. I was thinking if it was possible to filter the water so that all the small cells will be filtered out and only the bigger ones will remain to ...
3
votes
1answer
55 views

How is the growth of benign tumors suppressed?

A benign tumor has an outer layer of cancerous cells beyond which are regular cells (I Think). The Tumor must have some kind of boundary layer like a wall where somehow the cancerous cells can't ...
5
votes
1answer
81 views

Are There Exceptions to Animal Cells not Having Cell Walls?

In the January Issue of SciAm (discussing Haemophilia): When damage occurs to blood vessels, exposure of the blood to collagen in the cell walls and material released by the cells triggers the ...
14
votes
4answers
2k views

Why would a single celled organism evolve to be multi-celled?

I read a story this week on Richard Lenski who has been 'evolving' E. coli for more than 50,000 generations now. One comment I read was from someone who doesn't accept Evolution who pointed out that ...
4
votes
1answer
59 views

What is an operon?

What is an operon in a eukaryotic cell, and how does it regulate the expression of genes? I've already read Wikipedia, but it is not enough clear to me. Unfortunately my knowledge in genetics are very ...
2
votes
0answers
34 views

How organized is the inside of a cell? [closed]

I know cells have many ways of organizing and controlling what goes on inside their membranes. But just how ordered or chaotic is it inside a cell? Here's a few thoughts I had. Consider the ...