0
votes
1answer
21 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 ...
0
votes
0answers
17 views

Body part in motion after decapitation?

I'm sure following video is totally different than of other mammal after their body parts decapitated. In this video apparently, the snake is cut into three pieces. But when we look closer to the ...
4
votes
1answer
44 views

Do all prokaryotes have ATP synthases and an electron transport chain?

I was looking this up and I'm wondering if so far I'm correct about the following: For the most part eukaryotes do aerobic respiration, which involves glycolysis, the Krebs cycle and oxidative ...
0
votes
0answers
14 views

Could bioluminescence be controlled by acetylcholine?

In a more extended question, I was thinking if there would be a way to control the brightness of bioluminescence by muscle stressing. Obviously skin and muscles are different tissues, but still I ...
0
votes
0answers
26 views

Why don't bacteria evolve eusociality? [closed]

Given that there's a high degree of relatedness in bacterial colonies, why don't they evolve to be eusocial, when Hymenopterans with a smaller degree of relatedness already have?
1
vote
2answers
111 views

Does evolution head to some optimum? [closed]

Currently we have many species which are "good enough" for current environment, some species emerge, another die. So let's say that they could be close to some local optima. Does the evolution head to ...
0
votes
0answers
17 views

Dominant model Disease SNP

Say that you have genotyped a SNP in a case control setting, and get the following result AA AB BB Cases 17 51 29 Controls 39 44 20 where A ...
0
votes
1answer
53 views

Are there evolutionary advantages for the bee sting to kill the bee?

The question title says it all: are there advantages for the sting of a bee to kill the bee? It seems to me getting rid of this would have only advantages, and might've been selected for if a mutation ...
-1
votes
0answers
18 views

Structure of cell membrane [closed]

There is a small gap between the 2 protein channels in the structure of the cell membrane. Is that gap the plasmodesmata in (plants) or desmosome in (animals)?
0
votes
0answers
36 views

Is human regeneration possible? [closed]

A lizard has the ability to regenerate its tail. Is it possible by genetics to use this property on a human who is handicapped to regenerate their hand? Has this ever been tried in the past? Will the ...
1
vote
1answer
22 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 ...
0
votes
1answer
48 views

Electron Transport Chain in Mitochondria [closed]

I was researching cellular respiration, and this is a rather confusing part. I need help understanding the purpose of Complex II and how the ATP Synthase generates the energy to turn ADP to ATP.
-3
votes
0answers
38 views

Is there a separation between hard- and software in the brain? [closed]

In a computer, you have (very simplified) the software, imprinted on hardware. Comparable to the cylinder in a music box that encodes the music. But when I sing a song I can´t imagine that software ...
-1
votes
0answers
10 views

Organization braincells [closed]

Why do microchips have a flat architecture, in contrast to neurons, and why is the energy supply of chips not divided over all the parts of the microchips, as it is in neurons?
1
vote
1answer
22 views

What are chiasmata?

I have a confusion in understanding what chiasmata are. My ‘NCERT’ book says ‘The beginning of diplotene is recognised by the dissolution of synaptonemal complex and the tendency of the recombined ...
0
votes
0answers
20 views

Has anything evolved to prey on endoparasites?

Is there any organism which lives within a host but gains nutrition not from host cells/materials but by preying on the host's endoparasites? If not, what barriers might exist to the evolution of ...
0
votes
1answer
22 views

Enzyme kinetics: recommended literature to grasp the concepts better

I have had a few biochemistry courses, but I still feel confused and a bit scared each time they try to explain and apply enzyme kinetics or even chemometrics in different situation during class. On ...
0
votes
1answer
29 views

Blood antigens and immune response

In my textbook, the definition of an antigen is written as follows: Antigen: A substance that the body recognises as foreign and that can evoke an immune response The following image also confused ...
1
vote
1answer
22 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
0answers
32 views

If estrogen plays an important role in bone formation, why aren't men's bones far weaker than women's?

I know decreasing estrogen levels can cause osteoporosis, but men have less estrogen than women; why aren't men's bones weaker than women's bones?
1
vote
1answer
33 views

Does the order of amino acids matter in making up a protein?

For instance, if a protein is made of 2 amino acids, that is, AB, would the same protein form if the order of combination of amino acids become BA? If yes, would the behavior of interaction of that ...
1
vote
0answers
23 views

How fast the human eye can [temporarily] change its color?

I know that human eye can change its color during lifetime because of disease or medication (similar question on Biology.SE). And I know that it may change depending on the lighting. But I saw ...
-1
votes
0answers
24 views

cre recombinase works in two copies of a gene [closed]

Each gene has 2 copies.so when we are inserting lox p in a chromosome how it will be? how many lox p sites will be there for a specific chromosome and how to analyse the band size if it is ...
-1
votes
0answers
12 views

Asexual reproduction of snakes, with mutation to account for diversity

I saw this piece on Animal planet's Jeff Corwin show, I think. It was many many years ago, but I still remember it was fascinating. A landslide or an earthquake once separated a small chunk of land ...
0
votes
0answers
21 views

What the gene variation detection result can tell us about a cancer [duplicate]

We do a research on a particular cancer, now we have a result of the gene variation detection . What next steps do we need to do? we don't have a clear picture about this. Can you give us some ...
0
votes
0answers
32 views

An elementary question for gene variation detection procedure in a paper

“Samples were divided into subtypes; each subtype was considered separately as a test set, using the remaining subtypes as the control. In our analysis, chromosome arms were subdivided into ...
0
votes
0answers
27 views

What is the species of this butterfly?

What is the species of this butterfly?
1
vote
2answers
33 views

How do biologists quantify “gene expression” in experiments?

I've read papers which contain statements such as "control of gene expression is critical in biological processes". How exactly does one quantify "gene expression"? Isn't gene expression an umbrella ...
0
votes
0answers
16 views

Is it possible to inject pigments into a leaf?

Is it possible to introduce exogenic pigments into the leaves of a plant? And, if so, how could you do that? Goals: the plant should not die the pigment should be visible looking at the plant ...
1
vote
0answers
23 views

Identity By Descent vs Identity By State

Background The concepts of Identity By Descent (IBD) vs Identity By State (IBS) are central in population genetics, yet I fail to fully wrap my head around the definitions. You can find examples ...
1
vote
1answer
29 views

Hardy-Weinberg equilibrium generalized to add inbreeding (non-random mating)

Background Quoting from Gillespie's book The level of inbreeding is measured by the inbreeding coefficient, $F_I$, which is the probability that two alleles in an individual are identity by ...
3
votes
1answer
59 views

Why doesn't the rest of the body have something like the “blood-brain” barrier to protect itself from pathogens?

According to Wikipedia: "The blood–brain barrier acts very effectively to protect the brain from most pathogens". This is because the pathogens cannot pass through the tight junctions of the ...
4
votes
2answers
44 views

Why don't protons diffuse out of the mitochondria during chemiosmosis?

If the outer membrane of the mitochondria is very permeable, how do mitochondria maintain a proton gradient by pumping protons into the intermembrane space? Wouldn't they just diffuse into the ...
0
votes
1answer
45 views

Evolution to store limited Fat

Why are our bodies not evolved to store only limited amounts of fat, which won't kill us with all diseases associated with obesity? Wouldn't obese people die faster and clean the gene pool for people ...
-1
votes
1answer
49 views

How can two individuals of the same species have different chromosome numbers? [closed]

It is known that male drones develop by arrhenotoky, and have haploid chromosome constitution, whereas the queen bee and workers are diploid. Thus we can see two different types of ploidy occurring ...
-3
votes
1answer
40 views

What are anagenesis and cladogenesis?

Are they two types of speciation? I have read wikipedia but can't figure out if they are really two types of speciation
0
votes
1answer
23 views

Why does meiotic recombination disrupt the independent assortment of genes on the same chromosome?

There are many sources that say that genes that are "linked" by being on the same chromosome assort with each other -- that when an allele is passed on that the gamete containing said allele will also ...
0
votes
1answer
23 views

Find the concentration of free receptors in a solution of 90% free ligand and 10% receptor-ligand complex, knowing only the value of kD

I could use some guidance on how to utilise the equation for the disassociation constant kD to find the concentration of free receptors [R] in a solution containing 90% free ligand [L], and 10% bound ...
1
vote
1answer
28 views

meaning of arrows in a 3D biomolecule representation

I would like to know what those arrows and also thin wires between them in this cd4 biomolecule's 3d representation mean. Thanks in advance.
0
votes
1answer
24 views

Genes that exist in old Affymetrix platform but not in the newer one

I am using two gene expression datasets from an Affy U95Av2 platform and an Affy U133 Plus 2.0 platform. When I map the Affy probe names to HUGO gene names, there are thousands of genes which exist in ...
3
votes
2answers
53 views

Light and Dark Reaction of photosynthesis?

I'm having a hard time understanding light and dark reactions because all the sites I've gone through provide different equations. Some say photolysis is H20 = H+ + O2 while some present it as H20 = ...
0
votes
1answer
22 views

Distance to source populations and/or environmental gradients?

How do you disentangle the effects of distance to source populations and environmental gradients when the environmental gradient occurs in the same direction as the source population? For example, ...
2
votes
0answers
44 views

Population size and genetic drift - What are the evidences?

Wright-Fisher model From the Wright-Fisher model of genetic drift, the random sampling of allele from one generation to the next is taken from a binomial distribution with parameters $2N$ and $p$, ...
5
votes
1answer
36 views

Are there differing organelle to cytoplasm ratio in animal cells?

Could anyone provide me with examples of cells with high organelle to cytoplasm ratios (heavily packed), and examples of cells with low organelle to cytoplasm ratios (sparsely packed)?
5
votes
2answers
56 views

Why upper surface of leaves is more green and shiny than the lower one?

I have properly googled this and got various answers. However, those answers do not provide an answer to the "Why" part of my question. Why is it that the upper surface of leaves is more green than ...
0
votes
0answers
16 views

General PCR is presenting with mysterious bands?

I have a small question. I recently performed a PCR reaction on FFPE DNA yielding a 125 BP fragment. However, a strange thing occured when I analyzed the results on our Fragment Analyzer. I got a ...
0
votes
2answers
59 views

Can photosynthesis take place if the plant is kept in ice cold water or not?

Can photosynthesis take place in a plant even if the plant is kept in ice cold water? I have googled this question, but so far have not found a satisfactory answer.
1
vote
2answers
52 views

What animal produces male gametes by mitosis?

The following question came up in my biology examination but I could not answer it: "What animal produces male gametes by mitosis?" I know that some plants produce their gametes by mitosis in ...
1
vote
0answers
15 views

I see various exposure limits for carbon monoxide, but what about one breath?

I see exposure limits for carbon monoxide like 50 ppm over 8 hours. This would correspond to a total inspired volume of carbon monoxide on the order of a few hundred milliliters. This exposure is ...
1
vote
1answer
40 views

Why aren't we immune to the “cold” [duplicate]

As far as I know, people suffer from the cold since ever. Why didn't and don't we evolve to resist it?

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