0
votes
0answers
3 views

Determining Age of a Fossil Based on Carbon-14 Decay

Suppose it is determined that a fossilized leaf contains 12.5% of the carbon-14 that was present when the fossil formed. How old is the fossil? (The age of fossils can sometimes be determined by ...
2
votes
0answers
18 views

HR being normal when being treated for the bends [on hold]

When you surface from diving too quickly; you get the bends - these are caused by gas bubbles forming in your lungs (especially nitrogen). This causes breathing problems if not treated since the ...
1
vote
0answers
8 views

How does Trifluralin kill newly germinating seeds, with almost no effects on established ones?

Trifluralin (2,6-Dinitro-N,N-dipropyl-4-(trifluoromethyl)aniline) is a pre-emergent herbicide used in landscape beds before the application of mulch (my use for it, anyway). It kills the weeds as they ...
-1
votes
0answers
6 views

Why light fighters have better cardio than heavyweights?

In boxing, lighter fighters, like featherweights and lightweights, seems to have a better 'cardio' (they get tired well slowler) than, for example, heavyweights. Why this happens?
1
vote
0answers
12 views

How does Isoxaben kill newly germinating seeds, with almost no effects on established ones?

Isoxaben (N-[3-(1-ethyl-1-methylpropyl)-1,2-oxazol-5-yl]-2,6-dimethoxybenzamide) is a pre-emergent herbicide used in landscape beds before the application of mulch (my use for it, anyway). It kills ...
6
votes
2answers
34 views

Can canines communicate with each other using gaze direction?

After researching why humans have white scleras when most primates have dark scleras, I stumbled upon the cooperative eye hypothesis. It proposed that white scleras may have evolved on behalf that it ...
0
votes
0answers
6 views

Polychromatic Fur considered against Monochromatic Hair

As I was gazing at a strand of fur that had shed from my cat, I was struck by the alternating bands of white, black, and tan. It seems that genetically coding for such an intricate coat pattern would ...
1
vote
1answer
41 views

Does increased cell turnover cause cancerous mutations?

If a certain set of cells or tissue are undergoing a lot of reproduction and repair cycles for some reason, does this inevitably lead to cancerous growths? If the mutation rate exceeds the normal ...
8
votes
1answer
52 views
+50

Why doesn't Clopyralid damage cool season lawn grasses?

I use Clopyralid (3,6-dichloro-2-pyridinecarboxilic acid) to kill broad leaved weeds in lawns. From my understanding, it works by mimicking an auxin which affects plant growth. Naturally this pulls ...
0
votes
0answers
10 views

List of dinosaurs synonyms

Is there a comprehensive list of dinosaurs synonyms with indications of which name is now considered correct? Something like "there's no brontosaurus, there's only Apatosaurus", "there's no ...
2
votes
0answers
63 views

Why did animals evolve genders? [duplicate]

The majority of animals have two genders, and both are needed in reproduction. It seems like it would be more advantageous for creatures to be hermaphrodites, since they could mate with any member of ...
19
votes
7answers
3k views

Is there anything that is completely non-toxic to humans at any dose?

Lately I have seen a number of unrelated "scientific" debates over whether certain substances should be outlawed because they are toxic to humans. My initial, informal reaction is usually to respond ...
0
votes
1answer
13 views

Thermodynamics of Forming Peptide Bonds

Which of the following shows the correct changes in thermodynamic properties for a chemical reaction in which amino acids are linked to form a protein? A) +ΔH, +ΔS, +ΔG B) +ΔH, -ΔS, -ΔG C) +ΔH, -ΔS, ...
2
votes
2answers
34 views

Why White Blood Cells (WBCs) do not react to foreign bodies like sperm?

Why do the white blood cells allow foreign bodies like sperm to exist inside body cavity without any reaction? White blood cells function is to fight against foreign bodies (from the text books).
2
votes
2answers
188 views

Why sperm count matter for pregnancy?

In order for a woman to become pregnant, sperm is needed. Why is sperm count so important for pregnancy? http://en.wikipedia.org/wiki/Sperm
-4
votes
0answers
31 views

Why sex is not allowed for children? [on hold]

Why sex is not allowed with children? As age increases, there will be decrease in sex hormones in males.
2
votes
1answer
14 views

Why are sperm cells not attacked by the female immune system? [duplicate]

Whenever a foreign particle enters into someone's body, it is attacked by the white blood cells. I just want how it is that, when sperms enter the female body, they are not attacked by the the woman's ...
5
votes
2answers
2k views

Why don't breast enlargements leave any marks of surgery on breasts?

If we get stitches, we get marks left on the skin, but there are no marks for breast enlargements. I saw a YouTube video about a breast enlargement wherein a doctor makes a cut. Where does the cut ...
1
vote
1answer
31 views

How do you determine if donated, stored blood is viable?

Think about stored donated blood; What should we check before transfusing it to a patient, to see if blood is still viable? What methods to use? What components should it have in what levels, to be ...
3
votes
1answer
34 views

why reptiles still stimulate even after the death?

I saw a video in which a decapitated snake head still tried to bite. I also saw a video in which a man was hit by the moving tail of a dead crocodile. So why do reptiles move even after the death? ...
1
vote
1answer
51 views

Enzyme Assay - pectinase

During assaying an enzyme at high temperature, the substrate (Pectin) is degraded by the high temperature rather than by enzyme, so, how can I minimize degradation of the substrate by the temperature? ...
8
votes
1answer
65 views
+50

How does Halosulfuron-methyl kill nutsedge, while leaving lawn grass and most weeds undamaged?

I use Halosulfuron-methyl to control yellow and purple nutsedge in lawns. This chemical acts by interfering with the acetolactate synthase enzyme, which quickly slows cell division, and growth at all ...
3
votes
1answer
26 views

SNPs and locations

I am new to reading raw DNA. When comparing two people's raw data, why does one person have a different SNP than the other, at the same location, on specific chromosome? But on a different chromosome ...
8
votes
0answers
96 views

Effect of pupil responses on the electroretinogram

The electroretinogram (ERG) is generally considered to reflect the retinal processing of a light stimulus, typically a photoreceptor response followed by secondary neuronal activity. I am wondering ...
7
votes
0answers
49 views
+100

Why are fly not scared when landing on a monitor with changing graphics?

I have been wondering why would insects in general, not be scared when important changes happen on your monitor where they have landed... If you move even just a finger, they are scared to death and ...
-1
votes
2answers
64 views

Why scientific names of animals & plants are made difficult to spell & remember?

Why scientific names of animals & plants are made difficult to spell & remember? Mango: it is easy to spell. Corvus splendens: it is difficult to spell
1
vote
0answers
27 views

Why not use lactase to aid the break down of lactose when making biofuels?

I did an experiment using nine different substrates (Lactose + lactase, corn, sugar cane, glucose control, wood, grass, no yeast control and yeast control) and observed their fermentation rates. ...
5
votes
2answers
1k views

Diffusion of Hypotonic solution into solution with glucose and starch

Cell walls are selectively permeable to ions and organic molecules. Sometimes the selectivity is passive and a reflection of the physical laws governing diffusion. We can do simple experiments that ...
-1
votes
0answers
25 views

A case study on copying a part of another person's paper to your own paper without mentioning the source [on hold]

Here's a quote from the paper: Stimulus-triggered fate conversion of somatic cells into pluripotency Nature 505,641–647 (30 January 2014) ...
3
votes
2answers
127 views

Would a plant need light if the chemicals gained by photosynthesis were given through the roots or as a foliar spray?

If you took the chemicals a plant gains through photosynthesis and put it through the plants' roots or by injection, or used as a foliar application for intake through the stomata, would the plant ...
4
votes
0answers
31 views

How to measure Na/K channel activation at the membrane level?

Assume that there are two different signals occurring on the ECG - during depolarization and repolarization in the standard ECG. I was advised not to use the standard ECG in measuring the exact ...
11
votes
1answer
95 views

Biological age of grafted plants

Suppose you graft a piece of an existing 'old' plant. Will it continue to grow having the same biological age as its parent? I.e., would it die at the same time as its parent? Or would the process of ...
2
votes
1answer
22 views

Are alleles passed down and shuffled randomly to the offspring during meiosis or fertilization?

If it does occur during meiosis, are the alleles switched over from one sister chromatid to the other during the crossing over process in Prophase I?
3
votes
1answer
16 views

How long do zebra fishes remain transparent?

As larva, zebra fishes are transparent, at least up to 5-6 days. I wonder what would be the upper limit of the transparent period. This is of relevance considering purposes for imaging. The question ...
0
votes
0answers
16 views

Protein x-ray crystallization reference for bioinformatics

I am looking for references or tutorials which introduce the field of protein x-ray crystallization, but without going into all the experimental details. I just want to learn whatever is relevant for ...
1
vote
1answer
35 views

dsRNA and immune response

If there is dsRNA in the cell (long enough), will it always bring immune response? What type of immune response it will be? Killing the cell if it has some amounts of dsRNA?
6
votes
0answers
56 views

How to define “Quasifixation” in continuous approximation of finite population?

Background Many models including the famous very first models derived by Sir Ronald Fisher in his early career, assume infinite population size. In an infinite population, an allele can rise in ...
8
votes
2answers
47 views

Are codons that map to the same amino acids interchangeable?

(disclaimer - I'm just getting interested in genetics so sorry if this is an obvious/silly question.) I see from http://en.wikipedia.org/wiki/Genetic_code in the section on the RNA codon table a ...
4
votes
2answers
89 views

How does menstruation proceed during one period?

I'm simplifying things here: A. Does a woman bleed constantly, like a drop every 10 minutes? Two hours without pad or tampon and your underwear is dirty? or B. Does a woman bleed suddenly a ...
0
votes
0answers
16 views

Cannot conjugate Biotin-labeled DNA to Streptavidin-labeled solid surface

I have been trying to immobilize DNA by the bioconjugation of biotin and streptavidin, but I cannot get this work. I added EDC and streptavidin to COOH ...
3
votes
1answer
37 views

Plasmid in the nucleus and gene expression

If we insert a plasmid into a human nucleus that contains exact copy of gene and all relevant promoters to produce some human protein, will the cell create functional protein from that plasmid only ...
4
votes
1answer
58 views

How does Pothos grow in only water?

The popular potted plant, Pothos aureus (or Epipremnum aureum) is happy to grow in a jar, with only water, for years. How is this possible when other plants need at least Nitrogen, Phosphorus and ...
15
votes
3answers
2k views

Why is high fructose corn syrup unhealthy?

I understand that high fructose corn syrup was found to have detrimental effects on peoples' health. Why is this so?
1
vote
1answer
20 views

Relation between a compound's toxicity and it's concentration level

I know that ammonia is toxic for the body since it disturbs enzymes of mitochondria. I want to know that why the ammonotelic animals don't get affected by it? I mean that even if there is plenty of ...
7
votes
3answers
100 views

Which fruit compounds affect the speed of fructose absorption?

Blood fructose levels are not regulated by insulin in the human body. This means that the body absorbs pure fructose very fast, and it raises the blood fructose levels rapidly. Do fruits/ vegetation ...
0
votes
0answers
11 views

Is there a comprehensive answer to teach how to classify between good and bad biology research paper? [on hold]

Is there an comprehensive answer to teach skills on how to distinguish between good and bad biology research paper on correctness? I want to self teach myself on graduate level biology before ...
3
votes
1answer
30 views

What does it mean when a patient suffering from malignant tumor (cancer) has been declared cured?

Comment by Anongoodnurse, has made me curious as to what a doctor means when (s)he says "The cancer is cured" to a patient. My idea up till this point (based on what I read and what I learned in my ...
-2
votes
0answers
14 views

What is the difference between plant's cotton & medical cotton? [on hold]

What is the difference between plant's cotton & medical cotton? http://en.wikipedia.org/wiki/Cotton
1
vote
0answers
9 views

Why there are two rounds of cytosine de-methylation in mammalian development?

I assume that the key biological meaning of cytosine de-methylation during germline development in germline progenitor cells is to reset imprinted genes and then set methylation pattern on these genes ...
2
votes
2answers
35 views

How to retrieve full gene names list and Entrez gene IDs and other annotation information from HUGO gene name list (in R or any)?

How to retrieve full gene names and Entrez gene IDs and other annotation information from HUGO gene name list (in R or any other software or language)? Is it possible ice versa: having full gene ...

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