5
votes
1answer
6k views

Why does milk contained in cartons of milk expand?

In the morning, I went to the fridge to drink some chocolate milk. At night, when I took out the same carton of milk, the packaging seems expanded, like some kind of air is inside. Explain please !
1
vote
1answer
92 views

How to compare two RNA transcripts?

In this paper, the cuffcompare RNA package is reported: Because of the stochastic nature of sequencing, assembly of the same transcript in two different samples may result in transfrags of ...
1
vote
1answer
97 views

Is each generation getting older? [duplicate]

So we know that our sperm and egg cells get set aside relatively early so that they aren't going through unnecessary cell divisions and causing DNA damage or telomere shortening, but since each new ...
3
votes
1answer
66 views

What is the simplest autotrophic cell?

Very simple cells, such as Nanoarchaeum equitans, require a host to provide certain essential ingredients for life. Complex life-forms (like humans) require a whole ...
4
votes
1answer
752 views

What determines whether an action potential is inhibitory or excitatory?

What determines whether an action potential is inhibitory or excitatory? Is it determined by the receptors, the neurotransmitters, or some other mechanism?
2
votes
0answers
33 views

What is the standard protocol for creating permanent stocks from freeze-dried bacteria?

I've received freeze-dried bacteria that I intend to use for a study I'm doing on slime mold; however, I've never dealt with freeze-dried, only frozen, bacterial cells. After reconstituting these ...
31
votes
2answers
4k views

How do we know the human species arose in Africa?

I have heard (from multiple sources) that the current scientific opinion is that the human species arose in Africa. What are the reasons for this opinion? If possible, simple and non-technical ...
5
votes
0answers
80 views

Is there a mechanism by which mammals lose interest in a partner after mating?

I'm reading the book called "Cupid's poison arrow", which revolves around a rather simple assumption: most mammals, including humans have a genetic program that is responsible for ever increasing ...
1
vote
1answer
167 views

Definitions of common and rare disease

Is there an epidimiological way to define rare and common diseases ?
4
votes
2answers
337 views

How to Extract RNA and perform RT-qPCR from very few cells ( ~5,000)?

I am currently conducting an experiment which involves FACS-sorting a specific population of cells using an antibody of interest. In order to validate the type of cells I have collected using this ...
4
votes
1answer
117 views

Why do low temperatures kill

Why can't we (human, or even unicellular organisms) withstand low (body) temperatures (5 - 25°C). I have a limited background in chemistry and biology, so this might be obvious, but not to me. I know ...
2
votes
0answers
66 views

Textbook for quantitative biochemistry with thermodynamics, as an alternative to Voet, Voet & Pratt (Fundamentals of Biochemistry)?

I'm looking for a great textbook on biochemistry that covers core topics: relevant aspects of thermodynamics, reaction kinetics, metabolism (e.g. krebs cycle, respiration, etc.). Ideally it would also ...
1
vote
1answer
144 views

Textbook/lab manual for mammalian cell culture

For general techniques involving molecular biology, I know of Sambrook and Maniatis Molecular Cloning which covers many of the standard cloning techniques. However, mammalian cell culture has many ...
1
vote
0answers
234 views

Would a VR headset exacerbate myopia or could it be used to retrain the eyes?

I've learned that there are two primary hypotheses to explain myopia: not enough use of distance vision or not enough sunlight If the distance between an eye and what it's focusing on is the primary ...
2
votes
0answers
25 views

Why are humans mostly right-handed? [duplicate]

Most sources I've seen say that about 90% of humans are right handed, and 10% are left handed. Why is this? My only guess would be that it has something to do with different parts of the brain ...
4
votes
1answer
1k views

Is there a relationship between Melatonin, Norepinephrine and depression in humans?

I'm reading a booklet on melatonin published in 1996, titled "Melatonin and the Biological Clock". This particular paragraph caught my attention and I would like to better understand what it means: ...
3
votes
0answers
75 views

Looking for a dichotomous key to identify primates

I'm looking for a dichotomous key to identify primates by physical and possibly geographical traits. Any format is fine (print, web, mobile app, etc.). Other than classroom activities and genetic ...
9
votes
6answers
504 views

Introductory literature for synthetic / systems biology?

I'm a computer engineer (MsC Computer Engineering) who's looking to switch into the field of synthetic / systems biology. I've got a comprehensive layman's understanding of evolution, genetics, ...
9
votes
5answers
6k views

Difference between genetic engineering and synthetic biology

I've recently seen the term synthetic biology being used to describe research involving genetic modification of organisms. What is the difference between synthetic biology and genetic engineering? Is ...
1
vote
2answers
615 views

Does ATP hydrolysis reaction have a high or low activation energy?

I was recently studying about ATP and how it functions as an energy carrier to all biological processes; however, I came across a confusing and paradoxical statement from two sources: (at 7:36) and (...
1
vote
3answers
85 views

Can a same gene stretch from one chromosome to another separate chromosome?

Can a gene continue on from one chromosome to another separate chromosome? For example, can part of an eye colour gene be on one chromosome and the rest of it be on the next chromosome?
2
votes
0answers
28 views

Wolbachia - cytoplasmic incompatibility

I read that cytoplasmic incompatibility in Wolbachia occurs when wolbachia-infected male insects mate with wolbachia-free female insects and produce non-viable offspring. By contrast, wolbachia-...
8
votes
2answers
2k views

How many species did Carl Linnaeus classify?

How many species did Carl Linnaeus (senior) classify?
0
votes
0answers
23 views

What chordata evolve first limb

I try to search when and what specie develop first bone limb. I also want to know when second pair develop. And first pair was front or back one? And why it stop only at 2 pairs. Are there any fish ...
4
votes
1answer
139 views

If the average resting potential of a neuron is -70 mV, why is there such a high ratio of potassium ions inside relative to out?

My bio teacher was discussing the ratios of different ions inside versus outside the cell. $$\text{OUT:IN}$$ $$\text{K}^+ (1:20)$$ $$\text{Cl}^- (11.5:1)$$ $$\text{Ca}^{2+} (10000:1)$$ $$\text{Na}^+...
2
votes
2answers
359 views

Why can't plasma proteins migrate from capillaries?

Why can't plasma proteins shift from capillaries to connective tissue but WBCs can be very rich in connective tissue even though obviously the WBCs had to go through capillaries. Another example: in ...
11
votes
1answer
717 views

Is the discovery of dominant and recessive genes the only reason Mendel matters?

We've known that offspring inherit various traits from their parents since (at least) Aristotle. In The Elements of Plant Hybridization, Gregor Mendel treats that fact as common knowledge. Clearly, we ...
2
votes
0answers
106 views

Does antibody staining / immunolabeling block or inhibit protein function?

In dissociated live cells, does staining them with an antibody block the protein's function? I am sorting cells based on their expression of a few marker genes, and culturing them post-sort for ...
3
votes
2answers
534 views

How do other primates treat their fingernails?

Do all primates have to trim their fingernails in some way, or do some primates' fingernails wear off through natural use? Also, is constant nail growth common to all primates?
3
votes
1answer
79 views

why do marine organisms orient with their bellies facing downwards?

why do marine organisms orient with their bellies facing downwards (like most creatures) given that they have relatively fewer constraints on their orientations than land or air organisms?
2
votes
0answers
33 views

Are there calcium channel blocking neurotoxins?

I am learning about calcium ion channel blockers (CCBs) and am confused whether there are neurotoxins that are CCBs. If they exist, what is an example of a CCB neurotoxin? What animals use CCB ...
1
vote
0answers
59 views

Name/Examples of Traits whose benefit is non-obvious and/or which evolve despite apparent mal-adaptivness?

I'm a graduate student in cognitive science doing work on people's explanations and learning, particularly having to do with natural selection. Often, students misunderstand natural selection as a "...
2
votes
0answers
32 views

What is the advantage of being tired after having a sex? [duplicate]

When we have a sex with partner, we feel so tired that we don't have any power to do anything. Then it would be disadvantage to the animals, of course humans too, for they are exposed to danger. For ...
2
votes
2answers
49 views

Determining the appropriate bioconjugate

I'm thinking of crosslinking two proteins. The crystallographic nature of the interaction and the binding motif for each molecule is know. The paper says the intermolecular contacts (over 50; van der ...
1
vote
0answers
53 views

What's the feedback regulation of Thyroid diseases and body temperature?

While going through the feedback regulation, the control of blood glucose level by insulin and glucagon is quite discussed in multiple materials including the textbook. I also understand the basic ...
10
votes
3answers
708 views

Have there been studies done to test Immortality of cancer cells in culture?

This website on cultured cancer cells () says cancer cells may be immortal. I am wondering if there has been any research done to find if cancer cells are really immortal. How old is the still ...
0
votes
0answers
16 views

phospholipid alterations in breast cancer

I'm interested in designing some experiments to assess how altering fatty acid synthesis affects phospholipid synthesis/lipid profiles. I've come across papers using standard inhibitors of FAS like ...
5
votes
4answers
14k views

Can nosebleeds cause death?

Can epistaxis or nosebleeds be a of cause death?
3
votes
1answer
35 views

Why is it so hard to find the amount of biotin in food? [closed]

According to the WHO publications biotin is a thing we need. Although its non toxic, so you can't get too much. However, excluding a few (small) lists that deal exclusively with biotin content there ...
2
votes
1answer
59 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 ...
14
votes
3answers
781 views

Why don't our cells merge when their phospholipid membranes touch each other?

Membranes of our cells consist of lipid bilayer (with some other components mixed in). Why wouldn't those lipid bilayers glue to each other and make the cells merge? If you suppose that it's due to ...
0
votes
0answers
11 views

What's the relationship between Drugbank drugs and SMPDB pathways?

In the 'pathway browse' panel SMPDB pathways and their corresponding Drugbank drugs are listed. What are the relationships between the drugs and the pathways? Some listed drugs are not in the ...
2
votes
0answers
62 views

How spermaceti makes a whale float

In the biochemistry book I'm reading (Box 10-1, Lehninger Principles of Biochemistry), an example is given in whales of how spermaceti (a wax located in the whale head), when at sea level is a liquid, ...
3
votes
1answer
109 views

Which plant is this?

I'm curious what plant this is! I found it at 37°52'23.2"N 122°16'55.3"W (north of Oakland, California, USA).
6
votes
1answer
54 views

Spatial learning in microorganisms

Has there ever been an experiment performed that demonstrated a form of 'spatial memory' in a unicellular organism? I'm imagining something analogous to the classic 'rat in maze' experiments, but ...
1
vote
2answers
265 views

What happens when we re-start a PCR reaction?

Recently when my PCR reaction was running there was power fluctuation and the entire lab was blacked out for a few minutes and unfortunately PCR that I was running got switched off. So, would it be ...
1
vote
0answers
172 views

Interpretation of qPCR results for low expression genes

I am attempting to validate existence of a transcript using 40 cycle qPCR. I designed primers for a unique feature of this transcript, and also designed primers for a sequence in the transcript that ...
-2
votes
1answer
42 views

Phosphorylation capacity of an enzyme [closed]

Let's think ProteinA can phosphorylate proteinB, proteinC and proteinD. Condition1: All proteins are expressed and proteinA phosphorylates proteinB, proteinC and proteinD. Condition2: Only proteinA ...
0
votes
0answers
9 views

List or database of regulatory SNPs [duplicate]

I am looking for lists/databases of known (primarily homo-sapien) regulatory SNPs One resource that I have already found that used to (now inactive) accomplish exactly this: http://oreganno.org/ "...
7
votes
2answers
218 views

What are some (bioinformatic) methods to characterize potentially novel gene transcripts?

I am working with a few novel transcripts of genes- before I confirm their existence experimentally, I would like to perform some bioinformatic analysis. I have already considered coding potential, ...

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