A cell is the smallest functional unit of life.

learn more… | top users | synonyms

5
votes
1answer
49 views

Should we induce fever to assist healing?

I am currently reading "The Fundamentals of Anatomy Physiology" 10th edition, and have found it an incredibly interesting book. I have just been reading about the lymphatic system, and the various ...
5
votes
2answers
73 views

Do changes in an organism's cell modify the genetic information it uses for reproduction?

What I'm actually interested about is whether a modification in one cell during the life of an asexually reproducing organism affects its genetic information? Which cell's genetic information is used ...
0
votes
0answers
21 views

alternative ways to detach cells other than trypsin [duplicate]

So I have an A549 (rather "sticky" cells, they usually take about 7 minutes to trypsinise) cells and I cannot use trypsin or tripLE as this will skew my ELISA results. I have tried scraping the cells ...
1
vote
2answers
53 views

The Ancient Kingdom of Monera

Why exactly were bacteria and archaea kingdoms separated from the now unused kingdom of Monera? Aren't they the same? They are both prokaryotes, so what is the difference?
4
votes
1answer
43 views

Do cell membranes have more phospholipids in one layer than in the other?

Assuming the cell membrane to have a spherical shape, geometry tells us that the area of the inner leaflet is smaller than the area of the outer due to the difference in radius between them. Does this ...
1
vote
0answers
8 views

Plants and animals ability to survive polypoidy conditions [duplicate]

In mammals the condition polyploidy produce something euphemistically termed "general developmental disruption" ,practically speaking this means system meltdown which happens very quickly. There is ...
3
votes
0answers
16 views

Procedure for doing western blot [closed]

I am writing a step by step guide for doing a western blot for a class. It is intended for any one with basic Biology lab skills. I am hoping people will review my draft and give feedback on how to ...
1
vote
3answers
53 views

Can a portion of human skin cells be modified in some way to generate light? [closed]

I have come across some species of living organisms who are able to emit light at whim. Can that ability be incorporated into a portion of human skin (a specialized tissue)?
2
votes
0answers
26 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!
2
votes
1answer
33 views

How semi-synthetic cell with artificial DNA works

I know that by now this is old new but I heard that a cell that used a synthetic pair of nucleotides, called X and Y, have been made. My question was, how did the cell understand the X and Y ...
0
votes
1answer
88 views

Apoptosis vs necroptosis

I understand that apoptosis and necroptosis share the same upper part of the pathway, but I cannot seem to distinguish when is each one activated? From my readings, it seems that when procaspases 8 or ...
2
votes
1answer
161 views

Active & passive transport question

If an element, ion or molecule is found in a cell is it possible to tell which method of transport was used? for example if a hydrogen or sodium ion was found in the cell could you tell if it got ...
0
votes
2answers
76 views

If DNA is the input, what is the output? [closed]

How does cells use the DNA inside them? I am looking on DNA as a strip of tape of Turing machine, but with machines its easy. I can read the tape and calculate the behavior of that machine. With cells ...
7
votes
4answers
173 views

How does an embryo know where to grow limbs etc

For example you have a cell or already a bunch of cells. Those cell(s) divide and after several week you have a grown organism, for example a human with limbs, several different organs etc. However, ...
2
votes
1answer
20 views

Mechanisms of Flagella

I know that dynein arms and microtubules are involved in the contraction of certain parts of the flagella to produce a wave motion, but I don't understand they are related to the 9+2 structure of the ...
1
vote
2answers
50 views

Is carbohydrate an important part of phospholipid?

My professor tells us that carbohydrate is an important part of phospholipid, but phospholipid is composed of Choline, Phosphate, Glycerol and two Fattyacid, and I don't think even one of them is ...
1
vote
1answer
101 views

Why are hard boiled eggs so homogeneous?

A eukaryotic animal cell is a complicated piece of biological machinery. Some major structures inside of the cell (see the image below) include: the nucleus, mitochondria, Golgi vesicles, and various ...
9
votes
1answer
699 views

Why doesn't the cell membrane just… break apart?

Forgive me if this is a silly question. I can't understand the basics. Why doesn't the membrane just... break apart? What's keeping the layers in the phopholipid bilayer together? I know that the ...
2
votes
1answer
51 views

How does core-conductor model correspond to an actual neuron?

Hi guys, looking at your average neuron, it is very difficult for me to imagine how this could be translated into a core-conductor model On the neuron above, where would be the intracellular ...
2
votes
1answer
243 views

Mitochondria - are they really separate organisms that once merged into eukaryotic cells?

Theoretically, mitochondria are said to be a separate organism that is concerned with its own life and its own processes. In fact, it even duplicates individually. I know a similar question is here ...
3
votes
2answers
41 views

Concentration dependent cellular processes

Are there any famous biological processes that depend strongly on a chemical concentration reaching a particular value, like some sort of switch? E.g. if concentration of chemical x reaches ...
4
votes
2answers
3k views

Why was the Davson-Danielli model rejected?

According to my textbook, Davson-Danielli's model of a phospholipid bilayer sandwiched between two layers of globular protein was incorrect. The nonpolar protein portions would separate the polar ...
1
vote
1answer
42 views

How long does it take for a cell to synthesize an enzyme?

Where can I find data regarding the times distinct cells take to synthesize distinct enzymes?
1
vote
1answer
42 views

Anaphase Microtubule Disassembly

Centromeres move toward the poles as the microtubules that connect them shorten. This shortening is due to the removal of tubulin subunits from the kinetochore ends of the microtubules. I'm confused ...
1
vote
1answer
69 views

How do penicillin resistant bacteria grow slower in the presence of penicillin?

We put 2 flasks inoculated with Bacillus cereus in 37⁰C: one with 100μg/ml penicillin + 50μg/ml chloramphenicol and the other without penicillin. We found that the OD is higher in the one without the ...
3
votes
2answers
84 views

Cancer growth and cell division [closed]

I am confused about the prerequisites for cell division and cancer. Which of the following is necessary for the cell cycle to progress? Hormones Growth factor Cyclins Cyclin dependent kinases ...
4
votes
2answers
123 views

Does increased physical activity increase the rate of cell division?

Ever since learning that the shortening of telomeres is linked to aging I've tried to figure out what causes cells to divide, and if it's possible to slow down the rate of cell division through life ...
4
votes
2answers
249 views

What's the difference between naive and memory B cells?

I understand that when naive B cells are exposed to antigens, they become memory B cells, but what is the functional difference between the two? I've looked at the quite a few article on B cells, but ...
2
votes
3answers
130 views

Why doesn't the cytosol dissolve the polar structures?

we know that cytoplasm of cells are filled with water molecules and other hydrophilic molecules so my question is why the water of cytosol doesn't dissolve the ionic part of the lipid bilayer or why ...
2
votes
1answer
65 views

Structure of biological membranes?

Integral membrane proteins have functional asymmetry i.e. they have two different domains of proteins performing different functions. these proteins have Tyr and Trp amino acid residues at the ...
3
votes
1answer
77 views

Hela live cell confocal laser scanning - reccommendations for good fluorophore that will show good movement

I've been doing a lot of live cell imaging lately mostly using hela cells expressing some EYFP based chimeric proteins. I'm building a video library for an art student here at the university who is ...
2
votes
1answer
308 views

What kind of a microscope do I need to see cell organelles?

I would like to study cells and looking for a microscope that would allow me to see: groups of cells individual cell cells organelles I would like to target insects and mammal tissue. I would be ...
1
vote
1answer
200 views

How does a fertilized egg form 23 pairs of chromosomes?

I am always confused about this...so when one cell which has 23 pairs of chromosomes undergoes the two meiotic divisions it produces four cells containing 1 chromatid of every chromosome pair so when ...
2
votes
1answer
498 views

Why do cells vary in shape and function when they have the same genome and the same organelles?

Why do cells vary in shape and function when they have the same genome and the same organelles. For example: why do all cells have nuclei but red blood cell's don't; why can't the cells of a eye ...
4
votes
1answer
2k views

Rate of cell division in humans

On average, how many cells divide each day in a human being? How long does a cell wait before dividing itself ? I have tried to look on the internet but surprisingly the answer is difficult to ...
0
votes
1answer
1k views

What determines the size and shape of a cell? [closed]

What determines the size and shape of a cell? They differ at different tissues / organs/ species