20
votes
2answers
1k views

How does RNA transcription determine which half of the DNA to use?

I feel that I might have a complete misunderstanding here. If DNA has two strands, how does the machinery of RNA transcription determine which one to transcribe?
1
vote
0answers
34 views

What determines the length to which hair grows? [duplicate]

Correct me if i am wrong, if we cut 2mm from eyebrow hair, it will grow 2mm and then stop growing, or if we cut 5mm, then it will grow only 5mm. My question is, does hair know how long to grow ?
34
votes
1answer
652 views

How does a cell sense its size?

Cells come in all sorts of sizes. How do they regulate their cell size to the point where similar cell types have a fairly mono-disperse size distribution? Reasked from ...
5
votes
2answers
65 views

Why would a mother reject her offspring if it has been “interfered” with by humans?

There was a recent incident at Yellowstone National Park in which tourists placed a bison calf in their vehicle, and that eventually led to the calf being euthanized. The National Park Service issued ...
0
votes
1answer
4 views

Physical activity in fasted state: Glucose for brain vs muscles

Let's consider this scenario: You do sports in the morning in a fasted state (i.e. without consuming any calories after waking). Your brain of course needs glucose and your liver probably still has ...
0
votes
1answer
22 views

How do bacteria use oxygen for respiration and growth?

I recently did an experiment with the rest of my class in which we had to see which of two solutions best aided a bacterium's growth. The bacterium had already undergone slight growth in the ...
0
votes
0answers
13 views

ID for any of the following insects. Karnataka, India. May 2016 [on hold]

Please help with the identification of the beetles/ bugs/ whatever insects they are. Thanks!
0
votes
0answers
23 views

FitzHugh–Nagumo system with diffusion

I was studying the FitzHugh-Nagumo model with diffusion and I quite do not understand the meaning of it. If we consider the system without diffusion, \begin{equation}\label{FHN}\begin{cases} ...
2
votes
1answer
153 views

What would happen if a cell is poked by a fine needle?

I had seen this question in an exam: A living cell has a protoplasm which is water based and demarcated by a lipid bilayer membrane. If a cell is pierced to 1/5th of its diameter with a very sharp ...
0
votes
1answer
38 views

Can magnetoreception occur in humans?

Magnetoreception is a sense which allows an animal to detect the Earth’s magnetic field in order to perceive direction, altitude, or location. Magnetoreception is present in bacteria, arthropods, ...
2
votes
1answer
45 views

What would kill you first water or cola? [on hold]

After discussing this with some colleagues, I devised the theory that you could drink more coca-cola in a single sitting than you could water, without killing you. Defining the volume it would take ...
0
votes
0answers
11 views

Requirements for In-Fusion Cloning Protocol?

I have some long primers I'd like to repurpose for an In-Fusion cloning project. The In-Fusion manual can be found here. They list a few examples of how the primers should match the vector, with 15 ...
5
votes
1answer
19k views

Why is my faeces black in color after eating Oreos

Why is my faeces black in colour the morning after I eat some Oreos? Day 1 : Eat a handful of Oreos & the next morning your stool is black. Day 3 : Eat a handful of cocoa flavored biscuits & ...
0
votes
1answer
32 views

Is tolerance unavoidable?

Do all psychoactive substances induce tolerance eventually? For that matter, do all receptor-binding substances induce tolerance eventually? It seems certain that different substances take different ...
4
votes
1answer
57 views

Do ants use something similar to the honey bee “waggle dance” to instruct the rest of the colony where to find a food source?

In the 20 years since we built our home, we've just recently had our first ant infestation. I'm familiar with the fact that ants leave scent trails to find their way back and forth between the ...
0
votes
0answers
25 views

What are Codominant vs Dominant Genetic Markers?

When talking about types of genetic markers, the adjective "dominant" and "codominant" are often used. I don't fully understand their definitions and found contradicting definitions. Foll and ...
-4
votes
0answers
15 views

Y chromosome in females? [on hold]

Do females, girls or women have one or more Y chromosome in any of their trillions of nucleated cells?
0
votes
1answer
13 views

Statistical genetics: Allele frequencies that follow a Dirichlet distribution

From Foll and Gagiotti (2008) (software BayeScan). They consider a model where several subpopulation are derived from a unique ancestral population. We consider a set of $I$ loci and let $K_i$ be ...
0
votes
2answers
43 views

Comments on Experimental result regarding Anti-Bacterial soap

After using soaps, we rinse our hands with water. Do bacteria from the water attach themselves to our hands again? If we wipe our hands to cloth after washing our hands, do bacteria from the cloth ...
0
votes
0answers
18 views

Fate of Acetyl CoA in well fed state?

When we have eaten well and take fat rich diet then in this condition Acetyl CoA produced from fatty acid breakdown will be gone to storage in adipose tissue or not? If it will go for storage then why ...
1
vote
1answer
33 views

Why is statistical mechanics relevant to RNA and protein folding?

This is a very naive question. As far as I understand the folding of a molecule is governed by the electromagnetic forces between its atoms and also between its atoms and the atoms in the surrounding ...
1
vote
2answers
286 views

What is the name of this plant with small, 5-leaved divided pink blooms?

I found this in a forest in Karlsruhe (Germany). The blooms are pink and have 5 leaves. Each leave is divided into two parts. It is pink and has a diameter of about 1-2cm.
2
votes
1answer
121 views

What is the name of this about 5cm high, grey, Beanie shaped fungus?

I found those below some stone stairs in Germany. The grass gives you an impression of the size (I guess the grass is about 5-7cm tall)
0
votes
1answer
26 views

Does mechanotransduction of cells play a role in the biocompatibility of titanium?

What exactly is mechanotransduction as the information varies between sources. Some sources indicate that mechanotransduction is the underlying principle where cells pull on the surface they grow on ...
1
vote
1answer
43 views

Nomenclature for mutations at specific nucleotide positions

I'm sure this is a basic question, but I couldn't find an answer anywhere. Let's say I'm provided with the location of a nucleotide as location as FGFR3:c.1843-35A>T. What does "1843-35" mean?
3
votes
0answers
17 views

Effect of ethanol and detergent on cell membranes problem

I am currently writing my biology report for an experiment I did on how ethanol and detergent affect the cell membrane. For my ethanol experiment, all went as expected BUT for my detergent experiment, ...
0
votes
0answers
16 views

Do all parasitic worms lack tango receptors on their skin?

I read that the parasitic nematodes lack tango receptors on the surface of their body. Is this true for all the parasitic worms?
-1
votes
0answers
37 views

Sequence Scan for CRISPR- sgRNA design & scoring question [on hold]

My lab is attempting to implement the Sequence Scan method from the publications "Sequence determinants of improved CRISPR sgRNA design" We have used the website referenced in the publication, ...
0
votes
1answer
30 views

Get Parent GO terms of GO term vector?

I have a vector of GOIDs that are specific GO IDs outputted from an enrichment analysis. I want to cluster my GOIDs by their parent GOID term. I used GOstats to do my enrichment analysis, and I have ...
1
vote
1answer
26 views

Why do mutations in Drosophila dsx (double sex) affect both males and females?

Reason: Loss-of-function mutation of dsx gene in female embryo leads to production of a nonfunctional protein that fails to repress male specific gene expression. So somatic characters of both the ...
0
votes
1answer
16 views

Why is flash light harmful to what aquatic life forms?

When visiting an aquarium, it's often not allowed to take photographs with a flashlight on. It is said that the flash light with very high intensity is harmful to the displayed life forms. I respect ...
1
vote
1answer
54 views

How to read cladograms/phylograms?

I understand the difference between cladograms and phylograms; the latter can show the evolutionary linkage over time. However, I am having trouble finding out which two organisms are most closely ...
0
votes
1answer
22 views

What is the relationship between stroke volume of blood and ventricular end-diastolic volume? [on hold]

I do know what each term means. That is, i know that stroke volume is: the volume of blood pumped by each contraction of a ventricle, while ventricular end-diastolic volume is: the volume of blood in ...
0
votes
1answer
32 views

Given the number of individuals who have a recessive disorder, how can one calculate the probability that the disorder was inherited?

Just to be clear, this is not homework. Suppose a biological family has five children, two of whom have a certain recessive genetic disorder that is not sex-linked. The parents themselves do not have ...
7
votes
1answer
190 views

Why and how is DNA synthesis so much faster then RNA synthesis?

DNA synthesis in E. coli is 20x faster than RNA synthesis at 1000nt/s vs 50nt/s. (Mirkin'05) I find that perplexing since DNA polymerization has better proofreading than the RNA variety, which ...
-1
votes
0answers
23 views

perception of time during sleep/dreaming [on hold]

Almost all of you might have observed at some point in your life that while sleeping, your brain creates a story matching to an external stimulus. Most of the times external stimulus is very short ...
2
votes
3answers
80 views

What type of tree is this?

This is a tree that I have been growing. I'm wondering if this is a mulberry, and if so, what kind? Location is Arizona.
0
votes
0answers
11 views

burying food scrap in soil: aerobic or anaerobic reaction?

I have been trying to avoid putting food scrap into trash so I have been burying them in the backyard. However, someone just asked me whether I was actually creating anaerobic reaction out of food ...
5
votes
1answer
44 views

Do two compatible tRNA codons bond together?

Can two tRNA with complementary anti-codons link together? For instance UUU with AAA. If not, why not?
1
vote
0answers
16 views

Mechanism by which water flows through xylem

I was doing a Cambridge iGCSE past paper when I came across the question: Describe the mechanism by which water flows through the xylem I thought the correct answer would revolve around the ...
0
votes
1answer
34 views

Mendel Genetics: Homework question

I'm looking at a question right now about Mendel genetics..... Q) When Mendel crossed a large number of tall pea plants with short pea plants, all F1 plants were tall. The F2 generation was created ...
0
votes
0answers
17 views

Why brain swells after brain death? [on hold]

Hot nose is a known symptom of probable brain death . I read that it happens due to cessation of blood flow to the brain from swelling. Or is hot nose sign only valid for death from intracranial ...
0
votes
0answers
14 views

Speciation : More rapid in sexual or asexual population [on hold]

A similar species of plants exist at two altitudes. At higher altitudes where pollination is low, the plants reproduce asexually. Whereas at lower altitudes where there are pollinators cross ...
3
votes
1answer
61 views

Do animals have different taste preferences within the same species?

Humans (especially children...) seem to dislike certain foods or drinks, that other humans seem to like. Common examples are coffee, french cheeses, milk, fish and cabbage. Are there examples of ...
0
votes
1answer
51 views

Maintenance of Diploid chromosome number at mitosis

I'm just not understanding this: A regular human cell is diploid - because it has 46 chromosomes, in 23 pairs. So that means that when the cell undergoes mitosis, it will still have the full ...
2
votes
1answer
6k views

How to translate a blood type used in Eastern Europe?

What are the I-IV blood type descriptions shown below (commonly used in Eastern Europe), and how do you translate them into the ABO-system?
1
vote
1answer
63 views

Standard notation for dominant and recessive allele

I'm reading through some science that could come up in my GRE equivalency. I've never been much of a biologist, more of a chemist/geologist....though it does interest me massively! I'm just seeing ...
1
vote
1answer
50 views

What nocturnal animal sound am I hearing in the trees in Maine?

Every year, during late summer nights (usually around 9:00 pm) in Maine, I hear a noise coming from high up in the trees. The trees I hear it from are mostly maple or conifer, but where I live there ...
-3
votes
0answers
40 views

How do cell organelles maintain their unique membrane composition?

Describe some of the ways that membranous organelles can maintain their unique compositions despite the continuous traffic of membranes and materials moving through them. This question is from Gerald ...
0
votes
0answers
18 views

Can i freeze in 40 degree warm water? [on hold]

I remember someone telling me that you can freeze in water even if its above your body temperature? Not that I am scared but what if you're in a hot tube for 30 hours while eating and drinking ...

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