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Questions tagged [cell-biology]

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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can a bacterium cell become a cancer?

I don't mean if a bacterium can be the cause of cancer inside a human. But can actually a bacterium changes in the way as normal cells change into tumor cells? So gaining such characteristics of a ...
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2answers
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Where does reverse transcriptase come from?

I can't figure out whether the viruses provide reverse transcriptase, or their RNA has the code for it, or the host cell normally contains it. Multiple sources just introduce the enzyme without ...
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How much shorter is the short arm of a chromosome? And why?

I keep reading that the p arm is shorter than the q arm. But I cannot find an explanation of how much shorter nor an explanation for the difference.
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Is there a good source for detailed molecular/atomic information about plant cells?

Can anyone point me to a good source for understanding the molecular/atomic details for the structure of a plant cell? For each element of the plant cell, I want to know what kinds of molecules/atoms ...
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What physiological processes give rise to a linear cell survival curve?

If we plot the number of surviving cells in a structure over time (assuming no replacement), the shape of that curve should imply something about the underlying process responsible for cell death. For ...
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What change would you expect in phospholipid orientation of the membrane if the enviornment were mostly heptane?

The external and internal environment of the cell is basically water, thus phospholipids organize themselves the way they do (bilayer). If the environment were to magically become mostly heptane, how ...
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How exactly do microfillaments change the cell membrane's shape?

I understand that they are concentrated under cell membrane and can contract, but the details aren't very clear. How do they attach to membrane, and in what direction do they pull? Do they draw two ...
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28 views

How cells determine how many enzymes are needed for digestion

How do pancreatic cells, epithelial cells of the stomach and intestinal epithelium cells determine the right amount of enzymes for digesting carbohydrates, proteins, fats? How does the pancreas ...
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1answer
38 views

How cnidocytes work?

I have googled for the structure of cnidocyte but images of google is unclear or complex .so please draw a simple understandable structure of cnidocyte .I know that cnidocyte works by osmosis but I ...
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There are small parts between Genes in an Operon that does not encode for any amino acids. What is the purpose of these parts?

What is the purpose of these parts in the translation process ? Picture to demonstrate below :
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0answers
35 views

Is it possible to create a biological radio? [closed]

If someone had taken the genome for a basic single or multi-celled organism, and had the understanding of genetic code to write his own program, is it possible on a fundamental level to create the ...
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50 views

How do molecular biologists determine biochemical pathways?

I'm new to this community, so hopefully this is the right place to ask this question. I know my question is really general, but in all of my biology courses we are merely taught the chemical pathways ...
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DNA replication and Protein synthesis

Is DNA replication required for Protein Synthesis or can proteins be synthesized without DNA being replicated?
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115 views

Do chromosomes line up as pairs in mitosis or meiosis?

Here is a question from the book SAT II Success Biology E/M (where the SAT is the exam taken by the American high school students): Homologous chromosomes line up in pairs in (A) metaphase of ...
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1answer
41 views

What is (roughly) the net charge of the DNA in an average human cell?

I was wondering about what general range for the net charge of DNA in human cells is in Coulombs. I imagine that kind of thing would be hard to measure but could be approximately calculated/estimated....
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Can mitochondria become cancerous?

Given that mitochondria have their own DNA and can replicate independently, can they ever become cancerous? For example, could a mutation in their DNA cause them to rapidly replicate, ultimately ...
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1answer
54 views

What's the decomposition rate of a mammal at -20 Celsius? [closed]

Is there any where to predict it without thawing? In terms of measuring it. What if the body was immersed in sugar prior to freezing?
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1answer
106 views

Can oral baking soda effect tumor cells in mice

Could anyone explain me please, how exactly (according to research article in Cell journal) adding the baking soda in drinking water can influence the acidity of tumor cells? What about homeostasis ...
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1answer
56 views

Tight Junctions in Cell Types

I took a quiz today on cell structure basics, which included cell junction types. I disagree with the "correct answer" according to the teacher. Here is the question: ...
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0answers
41 views

How do the bacteria producing bacteriocins protect themselves from it?

Whenever there is Col plasmid in a bacteria it will produce bacteriocins which will kill other bacteria around it. Why will the bacteriocin not kill the bacteria which has produced it? How does the ...
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1answer
71 views

What determines the metabolic pathways that a biological cell is able to carry?

For example: human cells (eukaryotes) can utilize the Kreb's cycle pathway to generate more ATP after glycolysis, but most bacteria cannot utilise the Kreb's cycle plant cells can utilise the ...
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1answer
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Why are the cells the smallest unit of life? [closed]

Please Tell me why the cells are called the smallest unit of life. According to me I know that they are called so because they are smallest entity which is alive that is they show the properties of ...
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0answers
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Is there a limit on how big a free living unicellular mono-nuclear organism can be?

When I looked for the largest protozoan I've found the name Syringammina fragilissima. According to wikipedia " .. Syringammina fragilissima, is among the largest known coenocytes, reaching up to 20 ...
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22 views

How hypoxia causes increase in intracellular $Ca^{2+}$?

Ischemia can cause depletion of ATP inside cell which can affect the efflux of $Ca^{2+}$ via energy dependent calcium pumps. This may (How?) cause increase in $Ca^{2+}$ ions intracellularly (Effect of ...
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1answer
170 views

How long does each of the stages in meiosis take?

For each stages of meiosis (i.e. Interphase, Prophase I, ...), I wanted to know the time between each stages either in percentages or minutes. However, while I could find the cell cycle for mitosis ...
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Why functional enzymes get denatured in coagulative necrosis?

In coagulative necrosis the architecture of dead tissues is preserved for at least some days. This is possibly due to denaturation of functional enzymes which causes cell lysis and therefore ...
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0answers
60 views

Low energy in phosphate bonds in ADP molecule

I know that a phosphate bond breaks in an ATP molecule to release a lot of energy which results in an ADP molecule. Why does the phosphate bond in ADP molecule not break to release an equal amount of ...
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What Does Transcription Factor E25 Activate When a Cell is Transitioning from G1 to S

Cyclin D/ CDK4 phosphorylates Rb allowing for the activation of transcription factor E25 during the G1 phase of the cell cycle. Supposedly, this transcription factor then activates as set of genes ...
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1answer
55 views

Reversal form of endosymbiotic theory?

Cell's organelles give us evidence that they might have been independent organisms on their own. Are there any single-cell microorganisms known to have gone so to say this way back as well, i.e. ...
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1answer
209 views

Why are there no multicellular prokaryotes [closed]

Why don't complex multicellular prokaryotes exits and also what made eukaryotes to become multicellular ?
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1answer
61 views

Can the face bones be “compressed” or forced together? What would happen? [closed]

Say someone doesn't like that their maxilla bone is too long because the height of the maxilla affects the placement, position and angle of the mandible relatively. If one were to apply mechanical ...
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2answers
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What is the chance a given gene will end up in a given gamete?

Let us say a somatic cell had a desired gene. This somatic cell was replicated during interphase so that it had two of the desired gene. It then underwent meiosis. My question then is, what is the ...
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58 views

Can I do a test for Hayflick limit in my body?

Are there any tests available for the public which can tell me where am I on a Hayflick limit? If Hayflick limit is 50 for example, the results I would like to have is this skin cells: 20 out of 50 ...
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1answer
52 views

Is every neurotransmitter receptor an ion channel?

This is a rudimentary question--perhaps the answer is well known to biologists, but is every neurotransmitter receptor also an ion channel? For example, NMDAR is a glutamate receptor and cation ...
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2answers
157 views

Can a viable embryo develop from the fusion of two egg cells?

For a zygote to form, two haploid gametes undergo meiosis and fuse during fertilisation. Since two egg cells (or even two sperm cells) are both haploid, is it theoretically possible for them to make ...
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1answer
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Sample suggestions for phase contrast microscopy

I am a non-bio student working on an academic paper recently and would like to have some sample preparation for phase contrast microscope. For it to work, I imagine the sample to be: Transparent; ...
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1answer
120 views

Is there a specific suffix for “within a cell”? i.e. in a similar manner to how -aemia refers to within the blood

Words like hyperglycemia and hyponatremia refer to the relative level of each component in the blood, not in the cell. Is there a suffix for within the cell? For reference I would like one word as an ...
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1answer
103 views

Which vaccines are damaged by freezing? [closed]

I have noticed that many of the freeze-sensitive vaccines are antigen only vaccines, for example Hib, pneumococcus, and tetanus vaccines. Why are these vaccines damaged by freezing? Are inactivated or ...
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1answer
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How does LDL leave the circulatory system and enter the interstitial fluid to deliver cholesterol to cells?

I have read that small molecules like oxygen and carbon dioxide diffuse through the capillaries, but larger structures can't fit through. This answer indicates that some proteins go through via ...
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2answers
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Why a cell contains all DNA when it only needs a few genes?

Is that what they called junk? Why does a simple cell have the DNA code for everything else when it just needs a few codes to function? Wouldn't that be a wasteful?
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What waste products do cells secrete in culture, and at what rate?

I am designing microfluidic chips for mammalian cell culture. One aspect I am interested in modeling is the rate at which I must renew media to ensure that: Cells receive enough nutrients Cytotoxic ...
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Does adenylate cyclase stimulate or inhibit acid secretion in the stomach?

I am confused about my teacher's notes. "Acid secretion is stimulated by ACh, gastrin and histamine. Histamine stimulates adenylate cyclase which increases cAMP production." When I looked this up ...
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1answer
144 views

Osmosis in red blood cells and bacteria

This is a question from an exam in my biology course. Bacterial cells and human red blood cells were inserted into one solution. Upon testing one hour later the blood cells exploded, while the ...
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2answers
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Is it ok to keep primers at 4 degrees?

I reconstitute my primers in nuclease free water ( no sterilised) this morning and I forgot them at 4 degrees, acording to the instructions, they should be storage at -20 after the reconstitution. I ...
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Cell signaling pathway inhibition

So cell signaling pathways are important, but how would one inhibit them? I can think of competitive inhibition, and inactivating protein kinases, but are there other methods that target other parts ...
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1answer
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What is going on with these buccal epithelial cells?

A pooled saliva sample from a 70 year old male. What is happening with these cells? Are these cells undergoing normal apoptosis? In the video, the cytoplasmic movement looks liquefied and jelly-...
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Experimental methods to demonstrate coupling of GPCRs [closed]

How would you experimentally demonstrate receptor coupling through each of the G proteins, Gs and/or Gi?
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0answers
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Does cell compartments and cells shell have the same meaning?

I encountered these two words today. Do they mean the same thing? Does a cell shell and cell compartments refer to a cell that has been emptied of its DNA?
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Cytoarchitecture v.s. Myeloarchitecture

My understanding is that cytoarchitecture refers to the cellular composition of tissues of the nervous system (here I’m wondering which tissues we are exactly talking about), while myeloarchitecture ...
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1answer
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Do all bacterial cells have a double membrane?

I’m reading that gram positive and negative bacteria have an inner plasma membrane surrounding the cytoplasm, then a periplasmic space, then an outer membrane. How does this compare to my general ...