3
votes
3answers
72 views

Can plants grow without photosynthesis?

Animals can survive without eating if nutrition is injected directly into their blood. Can the equivalent be done with plants? By injecting carbohydrate rich nutrient solution, either without ...
0
votes
1answer
24 views

Confusion over equations for population's heterozygosity vs. heterozygous individuals

On page 24 of Gillespie's Population Genetics, 2nd ed, an equation for $H$, the probability that two randomly drawn alleles are different by state, is given. $H$ is stated to be similar to the ...
1
vote
1answer
39 views

Does having to urinate imply that you are becoming dehydrated?

This question came up after I read another question that coffee does not dehydrate you, but instead acts as a mild diuretic. Does having to pee imply dehydration? Allow me to elaborate: When you ...
2
votes
1answer
30 views

What constitutes as the death of a bacteria?

I've read that some bacteria can survive a long time without food. What constitutes the death of a bacteria ? What process needs to take place for it to be considered dead?
0
votes
1answer
34 views

How to prevent a old promoter region from attaching onto a plasmid instead of a new one during ligation?

What I am trying to do is take out a existing promoter region in a plasmid, and replace it with a new one. So first I use the appropriate restriction enzymes to get rid of the existing promoter region....
0
votes
0answers
20 views

A question about cat coat colour genetics

I have a question about cat coat colour genetics. Concretely, the breed Russian Blue comes in several colours. The desired colour is "blue" which is black diluted and is recessive. See for example ...
0
votes
0answers
7 views

How can I verify the long term bio compatibility of an implant?

Is there a technique to find out if a material coating is biocompatible? One obvious method is implanting the object and waiting, but this carries massive risks and should not be attempted.
1
vote
1answer
24 views

Breathing's Role in Aerobic Respiration

It's my understanding that aerobic cellular respiration is summarized in the formula $C_6H_{12}O_6+O_2→CO_2+H_2O+ATP$ (unbalanced). The glucose is thrown through a series of chemical reactions, ...
11
votes
1answer
682 views

Why don't rats have a gallbladder, unlike other rodents?

It has long been known that rats do not have a gallbladder, though other species including humans, monkeys, cows, reptiles, dogs and mice, all have a gallbladder. In this paper from almost 100 years ...
2
votes
0answers
14 views

Where should I go for online information on animals endemic specifically in Mozambique?

I've been involved with the citizen science project "Wildcam Gorongosa" for over half a year now (website, forum). As there are lots of unexperienced volunteers, many questions are being asked. Often ...
-1
votes
2answers
53 views
1
vote
0answers
16 views

Dopamine receptor count: Role and Measurement

Can the Dopamine (DA) receptor count take a significant drop over the course of life or does it stay constant? I read that low D2 (Dopamine receptor type 2) receptor count does not cause Parkinson's ...
1
vote
1answer
36 views

Are a bonsai tree and its normal version the same species? [duplicate]

I would like to know if bonsai type of a tree is a separate species from its normal version. Do they differ by genes, or is it just a matter of different physical care? Can I grow a bonsai tree from ...
14
votes
4answers
4k views

Why does hair grow after trimming but remains at a constant length after a while?

Some hair especially body hair regrows after trimming but stops growing after a while. What is the mechanism behind control of hair growth and how is the length limit determined?
1
vote
0answers
31 views

Fabric melting spider juice

I live in the southern rocky mountains of Canada. I was in bed the other night when I saw a small scurrying shadow out of the corner of my eye. The source of the shadow was a small spider (95% sure it ...
0
votes
0answers
22 views

How do implantable devices interact with the human body?

Are there some general methods to prevent biochips implants for unwilling recipients? If implantable devices are embedded in the human body, how does the human body detect and react to foreign ...
1
vote
0answers
14 views

Why doesn't Poison Ivy cause a reaction under one's fingernails?

Okay, so I pulled up a bunch of Poison Ivy last week and I got itchy up and down my arms. I scratch and I think that causes the oil to spread causing more misery. However I notice that I don't get a ...
0
votes
0answers
23 views

What are the real chances of HIV transmission? [closed]

I am really confused about this matter (as far as transmission via sexual intercourse is concerned). I've heard a lot of versions from doctors and on internet. To be more specific: A pathologist ...
1
vote
1answer
23 views

How do you call the species that gives its name to a upper-level clade?

Just a silly question: I don't remember how the species giving its name to an upper-level clade is called. e.g. the name of family Canidae derives from Canis lupus You could say it is the "name-...
0
votes
0answers
34 views

Adaptation by standing genetic variation and fitness variance [duplicate]

I've read a couple of paper on Fisher's Fundamental Theory of Natural selection that states: $W(t+1) = W(t) + Var_{W}(t)$ Given a population with some degree of genetic variability, and assuming that ...
0
votes
1answer
60 views

what is the formula to establish ec50 reproducibility with respect to dose response curves for some drug

The EC50 is determined by fitting a standard curve to the experimentally obtained control values for each dose response curve using some software that does trial and comparison until satisfactory(...
3
votes
3answers
52 views

Can pathogens enter the bloodstream if the epidermis has been scraped off?

Assume that the epidermis has been scraped off by a fall (not just scratched). Also assume that the dermis is completely untouched. Does this allow pathogens to enter the body more easily, or does the ...
2
votes
1answer
94 views

Techniques to show a protein heterodimer-DNA interaction

It is known that c-Jun and fos dimerize to form AP1 factor that binds to a sequence on DNA containing PyPuGACGTCNNNNGAGGTCPyPU. In esophageal cancer cell lines there is no expression of the fos gene. ...
1
vote
5answers
648 views

Punnett Square Help

In fruit flies, red eyes are dominant over white eyes. Show a cross between two white-eye fruit flies. My question is... How do I know if the white-eye fruit flies are homozygous or heterozygous?
3
votes
2answers
47 views

Does an increased reproduction/mortality rate provide an evolutionary advantage?

If a species has a high mortality/birth rate, then it is able to adapt to changing environments more quickly than species that live for a long time. Without a high mortality rate, food and other ...
0
votes
0answers
18 views

Year 11 Seed Germination EEI ideas

I am doing an EEI on the effect of salinity on the germination of seeds (mung beans) and I need another element to increase the experiment difficulty. Would someone be able to assist me in adding this ...
0
votes
2answers
31 views

Are all prokaryotic promotor regions the same, or do they differ depending on the product of the transcript?

Are all prokaryotic promotor regions the same or do they differ depending on the protein encoded by the mRNA being transcribed? What I am thinking is that if activator proteins are a method of ...
-2
votes
1answer
37 views

Does tRNA contain parts with double-helix structure? [closed]

I read in some place that tRNA has a part which is double-stranded. I wanted to know if that part is similar to DNA (double-helix). (And I know that tRNA won't contain Thymine)
1
vote
3answers
388 views

Where are the evolutionary “inbetweeners”? [closed]

The problem I've always had with evolution is the actual lack of variation between animals. More specifically, the lack of observable gradual change between species. Take for example the hammerhead ...
0
votes
2answers
28 views

What amount of genes co-expressed should be expected in a tissue?

I am working with gene expression microarrays of tumor tissues and I want to use a program to find the clusters of co-expressed genes in order to know if some particular genes are co-expressed with ...
38
votes
5answers
12k views

Why don't mammals have more than 4 limbs?

Arthropods have 6 or more limbs and arthropods with 6 limbs appear to move faster than arthropods with 8 limbs so I wonder whether this might have something to do with fast and efficient locomotion. ...
0
votes
0answers
24 views

Query individuals with both WGS and RNA-Seq data

Using the SRAdb R package, I am looking to query individuals who possess both WGS and RNA-Seq data on the SRA. So far I believe I have been able to query specific samples with both WGS and RNA-Seq ...
3
votes
0answers
33 views

Scaling down amount of DNA for transfection: what factor to consider?

I am interested in transfecting HEK293 cells with a BAC. One paper suggests using 24 ug of DNA to transfect a 55-cm^2/10 ml culture plate. I am using an assay optimimzed for a 96 well plate so I am ...
3
votes
2answers
45 views

Is this in vivo or ex vivo?

This question has probably been asked a few times but I get the concept I just dont know how to apply it for this paticular experiment I aim to use cherry tomatoes and determine its glutamate content ...
0
votes
0answers
32 views

Problems with housekeeping genes

I have tried several housekeeping genes to analise the relative expresion of a cytokine for measure the inflamatory local response in mice ears, all the housekeeping genes I have tried are not stable (...
5
votes
1answer
46 views

How is a synapse held in place?

Here is a question I've never asked myself until now: All textbooks show synapses with a decently large synaptic cleft between the axon terminal and the dendrite. How is this connection held in place ...
12
votes
3answers
187 views

Is the amount of the soil reduced when plants grow?

According to the principle of mass conservation I think the amount of the soil should be reduced when plants grow. But this reduction is not observable so much. For example, some trees (big trees) ...
-1
votes
1answer
33 views

What legal possibilities exist to get access to articles behind paywalls? [closed]

Many publications, be it in high-profile journals, proceedings, book chapters or any other medium, cannot be accessed without subscription alongside substantial costs, even though most of the ...
3
votes
1answer
91 views

Does this patient have HHV6 or HCMV after transplant surgery?

I have been given mock results from a PCR test on blood samples taken from kidney recipient patients and their donors. The PCR reaction can detect single copies of viral DNA. I have been asked to ...
16
votes
4answers
72k views

What is a coupled reaction and why do cells couple reactions?

I was wondering what exactly a coupled reaction is and why cells couple them. I read the wikipedia article as well as several others, such as life.illinois.edu but I still don't get it. Could ...
1
vote
1answer
18 views

Are fish averse to extreme heat?

Terrestrial animals face two common sources of heat extreme enough to pose a danger to them: Sunlight and fire. It therefore stands to reason that they would evolve systems for sensing heat and ...
6
votes
3answers
81 views

Cancer biology: Can tumors form from cells that are genetically identical to non-cancerous cells?

Can a tumor begin to form without any genetic mutations? I'm specifically interested in a tumor which could later lead to cancer.
3
votes
1answer
77 views

How Much DNA do Siblings whose Parents are First Cousins Share?

On average, two siblings generally share 50% of their genome. How much does this increase if the siblings' parents are first cousins?
0
votes
2answers
51 views

How to assess if biological measurements follow a normal or a log-normal distribution

I am using a dataset composed by $m$ samples and $n$ features (genes). Each data point is real number. I want to understand how to preprocess data before analysis, in particular: do data points ...
20
votes
1answer
286 views

What's the mechanism for being mentally tired?

I notice that after long tests, or long periods of critical thinking, my body and mind feel noticeably tired. Why does this happen? Are the neurons in my head not firing as quickly, or is there just a ...
3
votes
0answers
23 views

Does increased calorie intake cause increase in libido in humans?

I'm interested in the effect of increased calorie intake on sex hormones and chosen mating strategy in humans. I'm aware that humans have a dual mating strategy - somewhere between pair bond and ...
0
votes
1answer
16 views

Is DNA sequencing coverage a function of sample purity?

How is coverage affected by the purity of a sample? And can coverage for a sample be affected by other things, like the library preparation or manner in which the sample was stored?
1
vote
1answer
33 views

Is it possible to have a random un-mutation of genes?

According to this article: Gene mutations can be classified in two major ways: Hereditary mutations are inherited from a parent and are present throughout a person’s life in virtually ...
1
vote
1answer
32 views
1
vote
0answers
9 views

Link between hypoglycemic events in Type 1 diabetics and clinical anxiety?

I recognize that the scientific community is aware that the chemical stress pathway is mediated by glucocorticoids. The pathway response initializes as a result of some sort of stress (potentially ...

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