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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13 views

Do bacteria grow on pure dry glucose?

I've accidentally touched pure glucose with my bare hands (fingers to be specific), which was intended for cell-culture. I'm worried that bacteria from my skin may start to grow on the glucose and ...
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1answer
29 views

Are ribosomes assembled in rough ER and Golgi body, or in the nucleolus?

I mean all the components, such as ribosomal RNA (rRNA) are synthesized in the nucleolus, but is the whole ribosome structure assembled in the nucleolus or is it also done in the rough endoplasmic ...
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1answer
96 views

Is metastatic cancer always lethal if uncured?

Can matastases spread in different parts of the body of an animal suffering from cancer grow in a limited way, such as not to cause much more harm that a benignant tumor in those parts of the body ...
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2answers
170 views

Are Gram negative bacteria classified as such because of their negative membrane potential?

Does the membrane potential usually quoted for Gram negative bacteria (e.g., E. coli) refer to the potential across both membranes? - If yes, then does the potential fall more over the inner or outer ...
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1answer
498 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 ...
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1answer
31 views

Can you replace glucose with glycerol in cell media?

In order to feed an animal cell in process called Respiration, can I replace Glucose with Glycerol? The Equation bellow: Glycerol + Oxygen -> Water + Carbon Oxide
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1answer
25 views

Question about Enzyme Inhibition in relation to Aspirin

I've been trying to learn a bit more about pharmacology, so bear with my ignorance. In short, I see that aspirin (in part) works by inhibiting cycloxygenase isoenzymes and that this inhibiting is ...
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1answer
66 views

Which are the last cells of the human body to die?

When somebody dies, which are the last surviving cells of his/her body? Those of hair, nails, or some other obscure but resilient cells? Shedding light on why and how they are so vital might boost ...
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0answers
21 views

What a cell needs to survive? [closed]

I'm looking specifically at animal cells. I'm not sure if it needs only Glucose and Oxygen for Aerobic respiration.
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2answers
220 views

Why do mitochondria fuse together?

Contrary to all of the textbook images of mitochondria that I have seen over the years, I had just learned that the mitochondria within a cell form a dynamic branching network along microtubule ...
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0answers
25 views

How do cells grow (ie. gain mass)? [closed]

I have some basic knowledge of the cell cycle. However, I don't understand how cells grow in the Gap phases. How do cells grow? And how does consumed food transfer mass to cells?
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1answer
68 views

How are ions 'pumped' across a membrane during electron transport?

A number of sites (including this one) that provide descriptions of photosynthesis state that high energy electrons 'pump' ions across a membrane. What is the actual 'pumping' mechanism? I've looked ...
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1answer
53 views

Why are considered to be exceptions to the cell theory? [closed]

If I am not mistaken, the cell theory states that: All living organisms are made up of one or more cells Cells are the smallest units of life Cells arise from pre-existing cells Aseptate fungal ...
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0answers
16 views

DNA. mRNA, tRNA [closed]

Can someone explain to me how transcription and translation works, especially the part about codes. And does amino acids has code or is it the tRNA?
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2answers
211 views

Randomness in living systems

The point of my question is not to talk about events that are uncontrolled by living organisms. My question is about controlled randomness, or I'd like to say adaptive random process. Process that are ...
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0answers
15 views

If spore possesses 10 chromosomes with 20 picogram DNA then calculate the amount of DNA in prophase II?

Options : a) 20 b) 10 c) 40 According to me, it should be 20 because a cell in prophase II is haploid after completing meiosis I reduction division. Also, spores are haploid, so amount of DNA should ...
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0answers
18 views

Production of energy in the form of ATP is concerned with?

Following are the options : a) Mitochondria b) Elaioplast c) Chloroplast d) Preoxisome e) Golgi Bodies Answer 1 - a) and b) Answer 2 - a) , c) and d) According to me , the answer is 2 because due ...
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0answers
15 views

What information do bipolar cells encode?

Short version: I don't see what information on-centre bipolar cells are actually capturing. Longer: Actually, the question could be extended to on-centre retinal cells as well, but I'll focus on ...
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0answers
19 views

Synthetic biology: examples of cell orientation driven by genes or genetic modification

First of all, forgive for the naive question. I know that genes can drive the shape of cells, as the sickle-shaped red blood cells. On the spirit of synthetic biology or tissue engineering, does ...
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1answer
44 views

Cell biology books

I'd like to know, what is the best list of books for non-biologist to understand, how signalling between organels is organized inside of eukaryotic cells. I really want to get how cell as separate ...
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1answer
50 views

Electron Transport Chain in Mitochondria [closed]

I was researching cellular respiration, and this is a rather confusing part. I need help understanding the purpose of Complex II and how the ATP Synthase generates the energy to turn ADP to ATP.
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1answer
340 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.
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0answers
58 views

What Chemical Trigger Causes Ectomycorrhiza To Change From Asexual To Sexual?

I want to know the trigger behind the change of asexual to sexual ectomycorrhiza when symbiosis with a tree root is formed. As ectomycorrhiza attaches itself to a root, it forms a relationship wherein ...
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1answer
45 views

Maintenance of Diploid chromosome number at mitosis

I'm just not understanding this: A regular human cell is diploid - because it has 46 chromosomes, in 23 pairs. So that means that when the cell undergoes mitosis, it will still have the full ...
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1answer
37 views

Are there differing organelle to cytoplasm ratio in animal cells?

Could anyone provide me with examples of cells with high organelle to cytoplasm ratios (heavily packed), and examples of cells with low organelle to cytoplasm ratios (sparsely packed)?
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0answers
20 views

Barcode exchange between neighbouring cells

I am currently interested in equipping animal cells in a tissue with individual barcodes. These barcodes should get amplified in the cells (not to a cell degrading extent, of course), and also ...
3
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1answer
110 views

How do lipid-soluble substances diffuse through the cell membrane?

It’s said that water-soluble substances can diffuse through cell membrane with less ease than lipid-soluble substances because the former encounters impedance in the hydrophobic region of the ...
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1answer
278 views

Why is DNA double stranded and RNA single stranded? [closed]

Why is DNA present as a double helix structure and RNA as a single helix? What causes the difference between them? Why they are not the same? what is the role of these differences?
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2answers
42 views

Cellular specific mass (in grams-dry-weight per pico liter)?

What is the cellular specific mass, in units of pgDW (pico-gram dry-weight) per pL (pico liter)? I suspect there is some variability between cell types, but this variability must be limited. Perhaps ...
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0answers
21 views

Membrane repair

Does Smooth endoplasmic reticulum play a role in membrane repair? I was reading a piece of writing in which they mentioned that they do participate in membrane repair but I could not figure out how.
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2answers
89 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
59 views

What are golgi blobs? [closed]

From a general google search I have come to know that golgi 'blobs'(also referred to as "golgi haze") are tubular vesicles formed during the interphase of mitosis. I would like to be reassured and ...
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1answer
34 views

How can I accurately measure glucose concentration in culture media?

I am trying to identify the best way to measure glucose concentration in culture media with E. coli. Now, I imagine I can use those glucose meters that diabetic people use, but unfortunately can't ...
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3answers
64 views

How are chemical reactions organized in prokaryotic and eukaryotic cells?

I realized I only have a vague understanding based on what remember from high school and I don't know if they ever really broke it down for us but: In general how do both prokaryotic and eukaryotic ...
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1answer
16 views

How is receptor production (recycling) regulated?

My understanding of receptor downregulation is that when activated, a receptor then gets absorbed into its cell, as shown in this weird video. It then gets either recycled or degraded. Tolerance ...
3
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1answer
55 views

How can neurons divide without centrioles?

I have read in my studies that neurons lack centrioles. If that is so, then how is it possible that new neurons are added to our brain? Does this have anything to do with memory loss?
14
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1answer
264 views

Why do specifically bananas go brown quicker in the fridge?

Perhaps the title should be: Why don't all fruits containing phenol residues go brown quickly when left in the fridge? Bananas go brown over time because of the oxidation of phenol residues. ...
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1answer
23 views

Thickness / size / volume of a macrophage

What is the thickness of a macrophage? From some available literature it looks like a macrophage has a 'circular' shape of radius ~10 microns. But I need the thickness to calculate its volume.
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0answers
15 views

What are the major cytological differences between mammalian and non-mammalian cells of the same tissue?

This may be a difficult question to answer, but do we have a comprehensive understanding of the structural differences between cells of the same tissue but different species? For instance, how ...
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2answers
140 views

Blebbistatin effect on vesicles

Blebbistatin is a drug that specifically inhibits the assembly of myosin in the cytoskeleton. What effect would you expect blebbistatin to have on intracellular vesicles? ...
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0answers
43 views

Are all the atoms in your body replaced with others over a 30 year period?

I was reading Creation - Life and How to Make It by Steve Grand. (This is the book that inspired Jeff Bezos to start the AWS initiative. ) In it he makes the following statement: Anyhow, by now I ...
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0answers
17 views

Issues with scratch test

I have a question about the wound healing migration assay, the scratch test. I have seen several protocols for the test, but there are differences in the addition of medium with FBS (1 night before an ...
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0answers
20 views

Animal skeleton composition?

I know human bone cells are made of calcium, carbon and phosphorus, however I am curious if there are animals with different bone compositions compared to the ones of humans?
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0answers
7 views

Is EGF-mediated proliferation symmetric?

It's known that the MAPK signaling cascade (say, ERK) is downstream of EGFR in epithelial cells, and that EGFR activation can cause proliferation in some cell types in some situations. My question is ...
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1answer
21 views

What is proton leak?

I have some idea about it. Is it the wasteful back flow of H+ ions through uncoupling proteins during aerobic respiration? Thank you
3
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1answer
61 views

Why are plant cells rectangular and animal cells spherical shaped?

Is that because the plant cells have cell walls and animal cells don't, or is there a function performed by the different shapes? Perhaps round shapes assist the movement of cells?
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1answer
31 views

What are respirasomes?

I have read wikipedia but don't understand it well. Do we mean Complex I, II,III and IV when we say respirasomes?
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2answers
434 views

Can you Transfer Cancer Between People via Saliva or other Bodily Fluids?

This may sound like a strange question. But could a Cancerous cell be transferred from one person to another from Oral contact e.g. Through Saliva, or other exchange of bodily fluids? I know that ...
8
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2answers
953 views

Why are skin moles (pigmented spots) circular in shape?

I have never seen a rectangular or triangular shaped mole. Is there any reason for why moles are roughly circular in shape?
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1answer
30 views

How exactly do we get “energy” from food? [closed]

I am captivated by human biology and I'm currently trying to understand the body and its processes in a greater depth. Thank you so much for your time and consideration! :-D I'm sorry for the rambling ...