2
votes
1answer
127 views

Photosynthesis - Light Intensity

Say I was conducting an experiment for photosynthesis. If I moved light closer to the plant, what effect would this have on the process of photosynthesis?
2
votes
3answers
542 views

Is there such thing as “half-life” of dopamine?

If a dopamine is released at T=0 and binds to receptor D2, what determines the time when the concentration of this neurotransmitter bound to the receptor reaches half of the original concentration? In ...
2
votes
1answer
353 views

Fossils of intermediate stages?

If Humans are evolve from Monkeys, there must be stages in the evolution process, when it was 1% human and 99% monkey, 2% human and 98% monkey and so on. This is because evolution was a very slow ...
2
votes
1answer
476 views

Has the age at which menopause occurs changed throughout history?

I was reading recently that the age of menarche has decreased in the last 150 years, and was wondering if the age of menopause in humans has also changed recently? Would there be selective pressure ...
2
votes
1answer
484 views

Why does non-continuous sleep makes you feel tired?

Let's say, hypothetically, that you fell asleep at 10PM, and you were woken up by a noise at 1AM. If you went back to sleep immediately and woke up at 6AM, you will feel tired even though you had ...
2
votes
2answers
319 views

How are different types of cells created from zygote?

In the process of mitosis that starts from zygote, how do different cells appear? What happens that some cells become one type and some another? For example, is there a cell that divides into a ...
2
votes
1answer
706 views

Circulation through the liver in light of drug metabolism

I have a lingering question which stems from an answer that I gave to What hydrolyses aspirin within the digestive tract and blood stream? When a drug or any other substance is absorbed into the ...
2
votes
2answers
163 views

Can the body of any organism on Earth live without impairment both in vacuum, and within Earth's atmosphere?

I know from reading that a human in vacuum needs a space-suit to survive. Is the body of any organism on Earth capable of living equally in vacuum, and on/below Earth's surface within the ...
2
votes
1answer
259 views

Are Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70 positively charged or negatively charged? [closed]

Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70,are they positively charged or negatively charged ? And which other solvents can be used as a substitute to water for preparing solutions in each ...
1
vote
0answers
14 views

Possibility of creating a non-invasive biosensor on solid (non-homogenous) fish samples

My team is planning to create a biosensor to determine histamine level in fishes. That device will just be placed on top of the fish, in a non-invasive/non-destructive manner. Past studies homogenizes ...
1
vote
0answers
37 views

Why do plants produce so much more sugar than they use?

I recently asked the question, "Do plants need O2 to consume energy they've stored via sugar?" to which @canadianer responded, "Yes, plants require oxygen to generate ATP from sugar. However, they ...
1
vote
2answers
47 views

How does it make thermodynamic sense for photosynthesizers to turn CO₂ into O₂?

My understanding is that animal metabolism consists of exothermic reactions like $$\ce{C6H12O6 + 6 O2 ->6 CO2 + 6 H2O + energy}$$ This makes thermodynamic sense to me. Animals need an exothermic ...
1
vote
1answer
49 views

How does Haloxyfop control young grassy weeds in fields of broadleaved crops?

Haloxyfop (haloxyfop-P-methyl) is a selective herbicide used to control grassy weeds in young stages. The mode of action (iirc) is basically inhibition of acetyl CoA carboxylase (ACCase). Why does ...
1
vote
1answer
24 views

Dehydration from caffeine, alcohol and other

Tea, Coffee, Beer, Coke etc… I wonder if the benefit from amount of fluid we get from them is bigger or smaller then the handicap of dehydration. In other words it is worth to drink them if we want ...
1
vote
2answers
80 views

What does to “evolve” exactly mean? [closed]

In this article, the author says: Evolution isn’t “leading up” to anything, it just drunkenly limps along using the same set of tricks in slightly different orders. On other occasions, however, ...
1
vote
1answer
49 views

How does salinity affect the bonds of an enzyme?

According to my textbook, "Too much or too little salt can interfere with the hydrogen bonds that hold an enzyme in its three-dimensional shape". I know that NaCl is held together by an ionic bond, ...
1
vote
2answers
136 views

Is there a difference between polarity and hydrophobicity?

From literature the two terms seem to be interchangeable when discussing protein domains and motifs. But biochemically, what are the specific differences between these two terms? For example what is ...
1
vote
1answer
52 views

Definitions of robustness and canalization

The concepts of robustness and canalization are fashionable today in the biology literature. However, I am not sure of their definitions and I am not sure either that all authors actually use the same ...
1
vote
0answers
26 views

How does Temperature influences the rate of protein turnover? [duplicate]

Question How (quantitatively speaking) does temperature influences rate of turnover of transcription factors? Which protein? As I am not looking for any accurate number I am talking about an ...
1
vote
1answer
59 views

Modelling how much cadmium a cell will be able to chelate with phytochelatins

I am involved in a synthetic biology project where I have to do modelling with ODEs. The biological process I want to model is the chelation of Cd2+ with phytochelatins, to know how much can be ...
1
vote
1answer
30 views

How to identify the genes that distal enhancers pair?

I am writing a project proposal and I have to talk about this problem: how to identify the genes that distal enhancers pair? I am really new to this topic and I don't know what it is all about. I ...
1
vote
1answer
370 views

Age of shells on beach

As a child I watched tiny fiddler crabs living in conical shells, and many years later I find that people study fossil turritellids. So now I wonder: how old are shells, typically, that you see on ...
1
vote
1answer
87 views

Has any creature ever devolved to be cold blooded? [closed]

Is this even possible? Because I have a non-scientific gut feeling that it is irreversible. Whales and dolphins are evolved from land mammals, and they've remained warm blooded while it doesn't give ...
1
vote
1answer
52 views

difference between ischemia and oxygen-glucose deprived medium

Ischemia is roughly defined as insufficient blood flow to a specific region of the body and in the literature it is generally considered as causing oxygen and glucose deprivation in the tissue and ...
1
vote
0answers
19 views

Classification of degree of infested areas by pine processionary moth on regions

I'm making a thesis about pine processionary moth distribution on the regions of algeria! i'm making tests about if there are spatial autocorrelation of this insects on the regions. and i'm doing ...
1
vote
0answers
43 views

$F_{ST}$ and the genetic variance in metapopulations

From this video (21'15''), the speaker gives the following formulae in order to calculate the between and among populations genetic variance from the $F_{ST}$: $$V_{Among Pop} = 2 F_{ST}V_G$$ ...
1
vote
1answer
47 views

Anti-parallel DNA code operons

Coming from a software engineering standpoint, suppose I have a string of code like so: ... 5'-ATAGAC-3' ... ... 3'-TATCTG-5' ... Assume the above code is part of a larger segment. Now, reading ...
1
vote
1answer
61 views

Do cell walls prevent cancer?

To my knowledge plants do not have an uncontrolled growth disease similar to cancer. Is the function by which they avoid uncontrolled growth related to their cell wall and preventing damage to ...
1
vote
1answer
46 views

How are new chromosomes replicated into the next generation via sexual reproduction?

If an individual has a new chromosome, which is very unlikely to happen, he will not have any luck in finding a sexual partner with this same trait. How will the offspring inherit this trait. And ...
1
vote
1answer
60 views

Appropriate statistical test for a student lab?

I am a HS Bio teacher and doing a microevolution lab involving candy. Essentially students use four candy types and push them together until one cracks (Nat Sel). They also do simulations of ...
1
vote
1answer
72 views

What does min mean?

I read that "trp operon is located at 27 min on E.coli chromosome." What does "min" mean ?
1
vote
1answer
151 views

circularizing DNA molecules?

I have been reading about next-generation sequencing technologies that can sequence long reads. Even though the origin of my question is sequencing technologies, the question I am asking is about the ...
1
vote
1answer
33 views

What are good data on the Human Metabolic Model and where can I get them?

Trying to get a good SBML representation of the Human Metabolic Model for use in Flux Balance Analysis and drug targetting (i.e. gene knockout) simulations. What are good sources for these data? ...
1
vote
2answers
140 views

How do you find pre-miRNAs from mature miRNA Blast output?

So in short, I did a blastn with standalone blast using all known miRNAs against the EST sequences in a genome (word length 7 and e-value 0.01). Now to confirm one of the next steps would be obtain ...
1
vote
1answer
407 views

Amber eye color in Neolithic Africa

Given what we know of the genetics of eye color and their historical distribution, is it possible or at least plausible for a person born in the Horn of Africa during the early Neolithic (ca. 9000 ...
1
vote
1answer
191 views

Birds and Dinosaurs

This came up in an argument with some friends. I know that birds are direct descendants of dinosaurs, shown pretty clearly through the fossil record. However, is it proper to say that birds are ...
1
vote
0answers
40 views

Pharmacodynamics of Ethinyl estradiol + Drospirenone and interactions with istotertinoin

Does pharmacodynamics of Ethinyl estradiol + Drospirenone in OCP pills like (Yaz, Yasminelle etc.) while using isotretinoin (Axotret, Roaccutane etc.) is changed? Does isotretinoin weakens the OCP ...
1
vote
1answer
65 views

Effects of smoking tobacco compared to inhaling other smoke

How much less dangerous is breathing smoke from burning wood and coal compare to smoking tobacco? Edit: Sorry. I should have made the question clearer. If this were an experiment, it would be set ...
1
vote
1answer
156 views

What type of mutation causes Progeria?

I'm doing my High School biology final on Progeria, and am wondering what type of mutation causes this disease. I know that the LMNA gene codes for the "prelamin A" protein, and that protein contains ...
1
vote
1answer
54 views

The reason why researchers usually use cell lines from “blast cells”?

What's the reason why researchers usually use cell lines from "blast cells" (so, immature, like lymphoblastoid cells) for measuring gene expression data? Is that they are growing up, which would make ...
1
vote
1answer
80 views

Body's decomposition

Does a human body decompose in a completely sterile environment ? If yes, what decomposes it ? And how fast ? What happens in vacuum ? Can it remain exactly the same ? Thanks
1
vote
2answers
64 views

Protocol for measuring stamina of arthritic mice

I am going to make some mice ill with arthritis. The medicine which I am testing as control is known to cause extreme fatigue. I think I've improved it. I'd like to humanly measure their stamina in ...
1
vote
2answers
116 views

Would it be correct to state that any biological difference between the sexes has to be found in the Y chromosome?

If the reason Why Men Don't Listen and Women Can't Read Maps is genetic, then one of the genes in the Y chromosome is to blame and in theory could be identified. Correct or incorrect?
1
vote
1answer
104 views

Why can't we propose a solid theory regarding origin of life?

What information is greatly lacking which does not allow us to propose a solid theory for origin of life ?
1
vote
1answer
162 views

If people with colorblindness lack one type of cone cells, shouldn't they be unable to recognize one particular color?

The 3 types of cone cells in normal humans allow them to view 3 types of colors and any color made from mixing and matching those 3. So, 2 types of cone cells should only allow to view just 2 types ...
1
vote
1answer
1k views

In what animal species is the sex ratio skewed in favour of the fertile female?

Ants have something like a single fertile female to several males. The same applies to bees, and larger animals - elephants too. Is the sex ratio universally skewed in favour of the female? What ...
1
vote
1answer
184 views

How to obtain bacteria samples?

Would anyone know how to go about obtaining samples of Salmonella or E. coli for purely educational purposes? Note: I just want to look at the stuff under a microscope.
1
vote
1answer
77 views

Can ant colonies have two “branches”?

Could an ant colony have 2 or more "branches" located far from each other (i.e. physically separated but interconnected nests) ? If so, how far is the limit?
1
vote
1answer
125 views

Single Nucleotide Polymorphisms and diseases

I am writing a report on how Single Nucleotide Polymorphisms occurring in each of these regions: Transcription factor (TF) binding sites Epigentic signals Splicing variants MicroRNA binding sites ...
1
vote
1answer
104 views

Hardy-Weinberg applied to three alleles and stimation of allele frequencies

I have this equation: Corresponds to HW in equilibria with three alleles: $(p+q+r)^2=1$ Expanding the square results: $p^2+2pq+r^2+2pr+q^2+2qr = 1$ I need to separate homozygous and ...

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