Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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.

0
votes
0answers
5 views

What was the cause of some egg-laying animals evolution to animal-laying?

Is there a specific reason for this evolution? Are no egg-laying animals more complex beings so their embryonic development requires more time and better nutrition conditions?
-3
votes
0answers
27 views

CELL BIOLOGY AND GENETICS [closed]

How the criteria of size, charge, polarity and hydrophilicity/hydropathy determine whether a molecule will pass through the membrane. The amino acid requirements of proteins and how they are placed ...
0
votes
0answers
34 views

Are formerly endosymbiotic organelles necessary for eukaryotes? If so, why? [closed]

It is widely known that the vast majority of eukaryotes have mitochondria, which are believed to have evolved from endosymbionts. The exceptions use related structures like hydrogenosomes which are ...
-1
votes
0answers
8 views

Haemoglobinic acid

I’ve tried searching for the structure of haemoglobinic acid but it isn’t anywhere. I was trying to find out whether H+ ions bind onto the same site as carbon monoxide and oxygen on haemoglobin or not,...
-1
votes
0answers
19 views

How is mRNA read by the ribosome? [closed]

I am aware that DNA is read in the 3' to 5' direction and then the resulting mRNA strand is created by the polymerase in the 5' to 3' direction. But during translation, which direction is the mRNA ...
2
votes
0answers
35 views

Why does K+ going out of the cell cause hyperpolarization?

I'm really confused by how the terms Hyperpolarization and Depolarization are used in Cell biology and hope somebody can enlighten me hopefully. Here's what they mean for me so far: Depolarization ...
1
vote
1answer
29 views

Number of dopaminergic neurons in VTA

Do you know an authoritative source for the approximate number of dopaminergc cells in the ventral tegmental area (VTA)? Ideally I would like to know this for mice, rats, as well as humans, but one ...
1
vote
1answer
56 views

Why do many cells together survive better than one cell alone?

I know that one cell with no ECM is subject to anoikis. That's why in general one cell alone not in its environment is dying. But are there advantages for a cell to live close to other cells even of ...
0
votes
0answers
15 views

Signals triggering ECM formation

What signaling triggers the formation by the cells of extracellular matrix ? I assume the mechanism is connected to autocrine signaling or paracrine signaling. Or maybe also stiffness sensing. Could ...
0
votes
1answer
9 views

Salt Bridge for Microbial Fuel Cell: Full or Partly Full?

I'm making a microbial fuel cell out of benthic mud and salt water in containers. My salt bridge will be made of agar and table salt solidified in PVC pipes. Does the salt bridge connecting the anode (...
0
votes
1answer
22 views

Which of the cell organelle is present in highest number in secretory cells?(mitochondria , golgi apparatus , endoplasmic reticulum ) [closed]

I am confused between Endoplasmic Reticulum and Golgi Complex. I also doubt whether Golgi Apparatus plays any role in secretion of steroidal hormones.
1
vote
1answer
55 views

Does a cell suspend or exit cell cycle at G0?

In an exam, there was one question which asked whether the cell exits or suspends cell cycle at G0 phase. I answered that it exits cell cycle but the official answer key says it suspends cell cycle. ...
-3
votes
0answers
25 views

Why did nature decide to make plasma membrane of animal cell hydrophobic?

I am taking Introductory Human physiology course on Coursera. The teacher said and I quote " the membrane of the cell is a hydrophobic barrier that prevents any charged ions or molecules from moving ...
0
votes
0answers
20 views

Can a lentivirus expressed protein that is undetectable by western blot be detected by BioID?

Cloned a single herpesviral gene into pCDH-EF!-GFP and see phenotypic effect on cells of interest and viral gene transcripts BUT unable to detect ANY protein using HRP boosted western blot. Even with ...
0
votes
0answers
19 views

What does it mean for a gametocyte to “reprogram” the genes inside of it?

I am aware that frequently clones have genetic defects not present in the donor organism, even though the two are genetically identical. The reason for this is that apparently the enclosing gametocyte ...
2
votes
1answer
41 views

Are epigenetic modifications the most stable mechanisms for cell differentiation?

Wondering what the general take is on what are the molecular mechanisms that are mostly responsible for cell type differentiation stability; ie, for a cell's identity to actually become 'locked in' ...
2
votes
1answer
75 views

Can radiation exposure cause cancer later in life even if no traces of radioactive material are present in the body anymore?

I had a long-lasting debate with a friend of mine about the Fukushima incident. The question that we tried to solve was if radiation or toxin exposure can cause cancer later in life even if no ...
24
votes
3answers
4k views

Are cells guaranteed to get at least one mitochondrion when they divide?

If mitochondria exist at random within a cell, isn't there a possibility that cell division will result in a daughter cell with no mitochondria? If not, what is the process for guaranteeing at least ...
0
votes
0answers
12 views

Insight on HPV vaccine to prevent/control reactivation of latent infections in those already infected

Some women experience reactivation of HPV infection in their 50's due to weakened immune system and weakened immune memory. Is it outside the realm of possibility that giving the HPV vaccine to those ...
-1
votes
0answers
15 views

Very long cells besides neurons

In the human body single neurons can approach a meter in length. In other words the sciatic nerve is made up of (myelinated) axons, and each axon that runs from the spinal cord to the big toe is part ...
1
vote
0answers
46 views

Protein misfolding [closed]

Protein misfolding is usually prevented by molecular chaperons. Rarely, the chaperons are not able to prevent the misfolding as a result of which the infectous molecules called prions will form. My ...
0
votes
0answers
13 views

How are codocytes or target cells formed?

How are codocytes or target cells formed in conditions like Thalassemia? And why do they appear like a target(as in why is there a central red surrounded by pallor surrounded by red?)
-1
votes
0answers
18 views

How do scientists genetically modify Interleukin for medical use, where do they source the gene and insert it?

I was wondering how scientists genetically modify Interleukin for medical use. Where do they source the gene from, what are the steps involved in genetically modifying Interleukin for medical use, how ...
2
votes
1answer
59 views

What does substrate mean?

I have been reading some literature on measurements related to biofilms. In some articles the word "substrate" seems to stand for the material on which a biofilm is growing. In other articles, it ...
0
votes
0answers
51 views

Stopping all intracellular activity in a reversible fashion

I have never studied biology but the following question seems meaningful to me. Suppose I take a cell, not that of a unicellular organism, but a human cell. Normally, there are some intracellular ...
0
votes
0answers
12 views

Endocytic pathway: Macropinocytosis

So I'm trying to understand this phrase: Unlike other endocytic pathways, macropinocytosis is acutely induced by growth factors From the following paper The 4 endocytic pathways I know of are ...
-1
votes
1answer
70 views

Chargaff Rules (confusion) [closed]

A professor of mine wrote that: $\frac{A+T}{G+C}$ is constant in double stranded DNA of different origin. However The Chargaff rules state that due to base pairing in the DNA it holds that : $A=T$ ...
2
votes
2answers
67 views

Do histones constitute the largest proportion of the protein in chromosomes at mitosis?

Do histones contribute more (by mass) than non-histone proteins in the chromosomes formed during mitosis?
0
votes
1answer
62 views

Is all of the DNA used by genes (encoding DNA)?

My intuition tells me no, since only 1.5-2% consists of exons, so this statement would be wrong. The correct statement would have to be: only about 1.5-2% of the whole DNA is used by genes (encoding ...
1
vote
1answer
40 views

When do the first neurons appear in humans?

According to this Neural Plate The neural plate appears in day 18 in humans (very specific). and according to this Neural Plate (wiki) The progenitor cells that make up the precursors to neural ...
0
votes
1answer
39 views

Classes of Graphs used in Biology

I am a student of Mathematics.Since I found no better place to ask my question I post it here. I was looking for some classes of graphs which are used in biology. I came across this particular class ...
0
votes
0answers
31 views

In cell division, are daughter cells “newer” than the parent cell?

I learned that cells go through cell division to generate new cells to replace dead or damaged cells. Are the daughter cells "newer" than the parent cells? For example, the parent cell has an "age" ...
0
votes
0answers
14 views

Length of cell cycle dependancy on nutrients, pressure, temperature or other factors

How is the duration of cell cycle influenced by the concentration in nutrients, mechanical constraint, temperature or other factors ? And can it change strongly ? Meaning there are 2 possibilities, ...
1
vote
0answers
42 views

Does the molecular composition of human body change after a period of time?

I was discussing change in human biology over time and my two in-laws charged in saying, "we're molecularly different after x". I didn't pay attention to what time period they exactly mentioned (hence ...
0
votes
0answers
14 views

Pits, symplastic or apoplastic pathway?

After water has moved through the endodermis through the Casparian Strip, water continues to move down the water potential gradient into the xylem vessels through the pits, is movement through the ...
1
vote
1answer
58 views

Does digestion require hydrochloric acid?

Would our digestion function any differently if we secreted something else, like sulfuric or nitric acid, instead? I'd assume an acidic environment may be required, but not sure if chloride is also ...
1
vote
1answer
48 views

How does the zygote divide much faster than other cells?

Normally a cell has a mechanism that controls its division. As far as I know, it checks surface area and stuff like that to decide to go for mitosis or not. However, this is not the case for a zygote....
0
votes
1answer
44 views

What are the (evolutionary) advantages of secondary transport?

Secondary active transport uses electrochemical gradients as a source of energy for the uphill transport of substrates (coupled to downhill transport of the ion). However except for in a few cases (e....
1
vote
1answer
20 views

Exocytosis of synaptic vesicles

I'm reading the following paper: http://jcs.biologists.org/content/123/6/819 The part I am really confused about is when they say: Exocytosis appears to use two alternative pathways: clathrin-...
0
votes
1answer
54 views

Spatially Encoded GPCRs?

I'm reading this paper, and I'm already lost in terms of what they mean by GPCR signaling is spatially encoded. The trafficking of G protein coupled‐receptors (GPCRs) is one of the most exciting ...
1
vote
2answers
123 views

What is a “pan-specific” antibody?

I am new to biology. I searched a lot to find an article that explains what "pan-specific" antibody is but I could not find anything substantial that would help me understand what it is. An example ...
0
votes
0answers
10 views

Rhodamine 123 Staining Function

How does Rhodamine 123 act as a probe for Mitochondrial Staining? What is the Exact Biochemical Basis? and can it Stain Chloroplast as well? Thanks in Advance
0
votes
1answer
17 views

Lysosomal Storage Disease

In my biochemistry class today we did a problem detailing two lysosomal storage diseases. In the first scenario, a cell line for I-cell disease can synthesize lysosomal hydrolases that are perfectly ...
0
votes
0answers
14 views

What is the mechanism behind cells being arrested in G0 phase by serum starvation?

When Dolly was cloned, it was not from a totipotent cell in an early embryo but a G0 phase induced cell originating from the donor sheep's mammary glands. I have found sources stating that a fully ...
0
votes
0answers
27 views

Difference in timescale of tissue movement vs cellular differentiation

I would like to better understand the difference in the timescales that cells seem to function. For example, how is it that muscle cells can move within seconds or less under stimuli such as hormones ...
0
votes
0answers
36 views

How can I learn biology by myself? [duplicate]

I am only 15 years old,and my primary school education hasn't been that good,also I forgot a lot of things. I would like to start again,and I am asking for your advice. What are some of the good ...
3
votes
0answers
23 views

Why are Barr Bodies usually seen along the edge of the nucleus under the light microscope?

We do a typical class exercise of aceto-orsein staining of buccal epithelial cells from female students to visualize Barr bodies under the light microscope. All the illustrations and pictures in the ...
0
votes
0answers
15 views

Examples of GDP (rather than GTP) activating cell signalling?

Is there any known example in a cell where a protein is activated by the hydrolysis of GTP to GDP, rather than the reverse in which a protein is activated when GTP binds to an inactive GDP-bound ...
-1
votes
2answers
64 views

Are there only a few alleles or groups of many alleles impacting protein structure and function?

I'm in the first year of Medicine and I'm studying Genetics and Evolution. I have this doubt in the back of my mind and I'm not being able to move forward without someone explaining me what's wrong ...
2
votes
1answer
44 views

How are primary monoclonal antibodies for screening mutant cells made, physically?

I'm working with a fairly common protein expressed in a large numbers of organisms, let's say a keratin-associated beta-protein. I'm trying to develop a process which requires primary-secondary ...