3
votes
2answers
6k views

What causes muscles to generate heat on contraction?

I'm curious what the exact cause is of dramatic heat generation that comes along with muscle activity. Can anybody explain this in understandable language?
6
votes
1answer
110 views

When are a female's eggs created?

Since a human woman is born with a set number of eggs, and meiosis is the process by which sex cells are produced, would meiosis in a woman happen before she is born or soon after she was born? If ...
3
votes
1answer
274 views

What does the empty space in the bamboo stem do?

Is the empty space inside a bamboo stem a xylem? And why is the space so large?
5
votes
4answers
1k views

What is SDS PAGE gel polymerization time?

I am working on 20% SDS PAGE. I want to know optimum polymerization time for 20% resolving gel and 6% stacking gel. If I increase the time then would it affect the band pattern?
5
votes
3answers
380 views

In what sense is the “histone code” a code?

Since I started learning about molecular cell biology, I have witnessed an increasing amount of attention to this thing called a "histone code." However, unlike the central dogma of molecular cell ...
2
votes
1answer
46 views

How are lesions in the RNA corrected?

I quite understand why thymine is present in DNA. So we can mark it out where cytosine undergoes a reaction and is converted to uracil. Then we can repair the DNA. But how can we make that out in RNA ...
3
votes
1answer
851 views

Why does our voice change when we get affected by cold or cough?

Why does our voice change when we get affected by cold or cough? I observed the voice change thing in so many people including me.
0
votes
1answer
348 views

Why are some vegetables/fruits seasonal?

How does the mango tree perceive the summer season, so tree starts producing the fruits? Every tree requires sunlight to grow but what limits the production of fruits to a certain season? For ...
1
vote
1answer
50 views

Double use of ATP in relaxing myosin & active transportation of calcium?

Is the ATP molecule which is bound to the myosin head for relaxation of the muscle (i.e., to break the cross bridge) also utilized for active transport of calcium to the sarcoplasmic reticulum during ...
2
votes
1answer
1k views

What is difference between breed, variant, subspecies and species?

What is the difference between breed, variant, sub-species and species? Are there any similarities between sub-species and sub-population of a region?
0
votes
1answer
139 views

Can someone help me analyze this article? [closed]

I need to read this article — "Beyond the rainbow" by Marie-Claire Koschowitz et al., for an exam. Following are some questions for which I could not figure the answer out after reading. 1) Why ...
10
votes
2answers
1k views

How is DNA Read

Little odd question here. I was told that DNA was read in groups of three. Assuming this, my question is: Which way would better describe how the DNA is read. (123)456789 to 123(456)789 to ...
4
votes
1answer
98 views

Potential to destroy viruses using prions? [closed]

Could a prion be used to sufficiently deform a viral protein in order to make the virus it is a part of incapable of reproducing? For example, take the common cold's VP1 protein and turn it into a ...
1
vote
3answers
223 views

Evolutionary chronology - if any, which species have evolved in the last 100 years

I heared somewhere, I cannot remember where, that there has not been an evolution observed in our lifetime. In life science class, right at the start, we was doing the usual MRSGREN (how to tell if ...
1
vote
0answers
138 views

Blood type frequency given probability

I have calculated the probability that any child will have a particular blood type from both the genotype level and the phenotype level assuming the human ABO Rh system is followed. Here are the ...
17
votes
2answers
606 views

Why should a tumor look like a crab?

Origin of the word "cancer" The disease was first called cancer by Greek physician Hippocrates (460-370 BC). He is considered the “Father of Medicine”. Hippocrates used the terms carcinos and ...
2
votes
1answer
69 views

Will gene mutations give rise to a protein that is shorter than the full length protein?

What is the relationship between deletion or insertion of nucleotide in the gene sequence and the protein's length that is coded out from the mutated gene?
1
vote
3answers
371 views

Are domesticated animals really “more intelligent,” or is that a myth/misunderstanding?

Often do I hear people speaking of how the domestic house cats are more friendly, less ferocious, less savage-like, and smarter and/or than their distinct but equivalent feline-species friends, like ...
4
votes
1answer
128 views

What is the name of this plant (see pic)?

This plant was found growing in Colombia.
6
votes
1answer
81 views

Can dolphins actually communicate linguistically?

Humans use "language." By language, I mean the thing I am using right now to talk to you. I know dolphins and orcas have very complex communication systems and also seem to process linguistic and ...
8
votes
1answer
153 views

Why do humans hear better between 2kHz and 5kHz?

I've recently seen the following image: Source: https://commons.wikimedia.org/wiki/File:Hoerflaeche.svg Translation (from German): The upper boundary (Schmerzgrenze) is where it starts to hurt ...
6
votes
1answer
81 views

Can anyone identify this chrysalis? (Identified)

It's about 5 or 6 cm long. It's on the outside (north facing) wall of my garage about a metre above ground level. Photo taken in Thailand near Hua Hin (about 12N 100E) in December 2014.
1
vote
1answer
43 views

Coniferous trees in temperare rain forests

In temperate rainforest, the dominant plant form is often coniferous trees (source). However, coniferous trees are also the dominant plant form in a very different climate and form a different biome ...
7
votes
2answers
107 views

Can the eye distinguish between pure and composite colours and how do we measure this?

Red light plus green light makes yellow light. Suppose I shone a pure red light, say 650nm, onto the same spot as a pure green light, say 550nm. The eye sees this two-peak spectrum as yellow. This ...
1
vote
1answer
50 views

Specialist evaluation for people aged under 40 years with stage 1 hypertension

Reading the NICE clinical guideline for Hypertension it says... For people aged under 40 years with stage 1 hypertension and no evidence of target organ damage, cardiovascular disease, renal ...
1
vote
1answer
91 views

Is there a rule for the annotation of the basepair or gene locus origin in bacterial genomes?

Since all bacteria have one circular chromosome, there is no designated origin to start the systematic gene locus numbering. Therefore, what is the rule to start the numbering at a particular point ...
1
vote
0answers
99 views

How do I import FASTA files into Haploview?

I'm trying to produce a haplotype network and so have decided to use the software haploview. However I'm having some problems importing my sequences into the software. I Have my sequences in a FASTA ...
3
votes
2answers
669 views

Action potential changes in low sodium concentrations but constant osmotic pressure

If I bathe a squid axon in a fluid that has high sodium concentration , why does the duration of action potential decrease compared to a control experiment in low sodium bath but maintained at the ...
1
vote
1answer
742 views

Deciduous trees in tropical rainforest

Some books says the dominant plant form in tropical rainforest biome is broad leaved evergreen trees. Other books say it is broad leaved evergreen trees and deciduous trees. What is the most accepted ...
3
votes
2answers
139 views

Choosing appropriate statistical test for ordinal data

Ordinal response variables show up often in biology, but I'm not sure how they are best analysed. Some examples are qualitative assessments (little, many, a lot) or risk assessments (low risk, medium ...
9
votes
1answer
474 views

Mass spectrometry versus western blotting for validation

I have mass spectrometry data (LC-MS/MS) from rat cortices under either drug or control treatments. The results were performed in triplicate (three pairs of rats, drug or control per pair). In ...
3
votes
1answer
759 views

What is the purpose of segments in citrus fruit?

What is the purpose of segments in citrus fruit? In my experience, each segment usually contains from zero to two seeds. I may have seen more but only rarely, if I remember correctly. What is the ...
8
votes
3answers
267 views

Evolution: One big population vs. many small populations

Let's say I want to evolve a bacterium that is resistant to an antibiotic. I want to do this by growing initially clonal populations of bacteria in presence of this antibiotic for a long time. I have ...
2
votes
1answer
192 views

G>T transversion VS. T>G transversion?

So I'm reading about how mutations in DNA can be caused by oxidative damage. An example of a product of oxidative damage is given: 8-oxo-7-hydrodeoxyguanosine My textbook says that this product ...
7
votes
3answers
1k views

What is the science behind the inaccurate perception of colors?

If I go into a green room (all walls are semitransparent and green) and spend some time - around 10+ min - in there, when I come out all my eyes see is white as pink. I see no (or very few other) ...
11
votes
2answers
213 views

Is there any evolutionary advantage of selection of L-amino acid over D-amino acid?

After listening to a scientific talk, I had this question that why in the natural selection process, are the L-amino acids selected over the D- form. However, we still we produce D-amino acids; ...
3
votes
1answer
114 views

Specific location where nerves converge

I'm looking for the "earliest" specific site where the 3 following nerves' sensory signals "converge": Trigeminal nerve Median nerve Superficial peroneal nerve By "earliest", I really mean the ...
2
votes
0answers
60 views

Are the Chromosomes organized in any meaningful way? [closed]

So my major is in pharmacy but both my master and my (currently in progress) doctoral degree are both in theoretical chemistry. My thesis is about quantum chemistry and proteins, but it has a certain ...
4
votes
1answer
55 views

What is the biggest facultative anaerobic metazoan known to science?

Related: What's the biggest obligate anaerobic organism discovered till now? I had always assumed that the Riftia tube worms were obligately anaerobic since they lived next to anoxic volcanic ...
-3
votes
1answer
1k views

Are transgenders born physically different from others?

Are all children born with only either male or female body parts (other than exceptions), or is there actually a natural third gender with the physical characteristics of both genders, e.g. the child ...
3
votes
1answer
723 views

Names of nerves in hands, shins and face

I am looking for the names of the nerves in 3 specific locations of the human body: The nerve running along the "top" (opposite side of the palm) portion of the thumb, from knuckle to fingernail ...
0
votes
1answer
44 views

Spironolactone's role with adrenergic agents in heart failure?

I am studying the treatment plan of adrenergic agents for heart failure. Then, in the group discussion, spironolactone was included. But I cannot understand how it is relevant when considering ...
7
votes
2answers
207 views

What does pain look like in wave form?

I am interested in understanding what "pain" and "hot/cold" look like, as far as waves signatures (signal processing) go. My general understanding of how pain (nociceptive pathways) and hot/cold ...
4
votes
1answer
1k views

Why are irises unique?

I heard that irises are different and unique for every person. According this link, probability of two irises having identical pattern is 1 in 10 to the 78th power. That's how iris scanners identify ...
0
votes
2answers
142 views

Binding of Multivalent Antibody to mutiple epitopes?

A multivalent antibody molecule such as Immunoglobulin M Immunoglobulin A etc bind to more than one antigens or epitopes but I am confused about that wheather these multivalent antibodies bind to ...
3
votes
1answer
31 views

Regarding tumors and their developement

If certain cells or tissue in a specific part of the body are for some reason overworked; like the cases of severe acid reflux damaging the throat repeatedly and the cells in the throat having to do ...
2
votes
2answers
4k views

Can I drink warm/hot tap water? [closed]

I live in Canada and tap water is drinkable, as a matter of fact, the government puts a little bit of flouride in the tap water so it cleans your teeth. My wife and mom always tells me not to drink ...
8
votes
1answer
353 views

Single long axon vs serial neurons

Based on the comments in this post and also this chat. For discussions and speculations please comment in the chat. The basic question is what is the advantage of having a single long axon such as ...
2
votes
0answers
40 views

How do I get recombinant proteins into the nucleus of mammal cells?

I know that there are Nuclear Localisation Sequencenes (NLS). They can be taken from endogenous or viral proteins and fused to the N or C terminus of my recombinant protein. Which is the best one? ...
1
vote
0answers
47 views

How do PER/CRY complexes accumulate in the cytoplasm?

The Period/Cryptochrome (PER/CRY) complex is a heterodimer that transcriptionally regulates circadian rhythm. When it is phosphorylated, it is transported to the nucleus and it inhibits a ...

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