4
votes
1answer
79 views

Is there a biological explanation for perceived deeper cognition whilst on cannabis?

Cannabis has been associated with literature, arts, and culture for centuries. There are a few features of the drugs affect on the human mind that account for this, however it remains illegal in most ...
3
votes
1answer
44 views

Species Identification: Coniferous tree, Italy

I noticed it close to the place where I work, I live in Italy Could you tell me the complete name of this tree? Particular of the leaves
2
votes
1answer
49 views

Why does the wavelength in curly hair differ?

Different people and animals have different wavelengths in the curls in their hair. I understand what purposes hair serves in protecting the skin from light and bugs. I am wondering about the eventual ...
3
votes
1answer
131 views

how to quantify toxicity

When going through this link, Table 1, what are the numbers mentioned there? How is one quantifying toxicity?
1
vote
0answers
30 views

Question related to pathogen population [closed]

Does only one pathogen of one species enter the host and cause harm to the host or is a certain number of pathogen populations of the same species needed inside the host to disrupt the functionality ...
0
votes
0answers
8 views

Can the salinity level in human blood be altered by diet?

My question is regarding is it possible to control the salinity levels in a human blood system by diet. I understand how salt works in the blood and just want to know if it can be controlled.
3
votes
0answers
26 views

Validity of measurements of respiration in isolated mitochondria

I've recently read a couple of papers on exercise and mitochondria, in which state 4 and state 3 respiration rates and ROS production are assessed in vitro after exercise has been performed (i.e., rat ...
5
votes
2answers
81 views

Relationship between lifespan and reproductive age?

I remember reading a while ago that there is a "general rule" in biology between an animals lifespan and when they reach reproductive age. In other words, an organism that reaches sexual maturity ...
0
votes
0answers
11 views

Does alcohol affect water potential across a tonoplast? If so, would it cause it to explode or implode?

This was a question I saw in a biology exam I recently sat. I know it affects the r-groups of the transport proteins, causing them to change shape and become leaky, but does it also affect water ...
2
votes
0answers
40 views

Has a restriction enzyme ever been tagged?

As part of an experiment that I am preparing, it would seem necessary for me to tag a restriction enzyme (HaeIII to be exact) with GFP. I began researching its domains to determine whether to tag the ...
0
votes
2answers
64 views

Are heterozygotes always fitter than homozygotes? Can inbreeding be beneficial?

Inbreeding is mostly not very good because when there is a 'disease' in one allele, the other could/would take over the function. But when you have two of the same genes/alleles, do they, or could ...
0
votes
0answers
59 views

Why do horses recycle their endometrial lining while humans don't?

How does not recycling the endometrial lining of the uterus benefit humans (and other organisms that menstruate), while recycling it is beneficial to horses (and other organisms that undergo estrus ...
3
votes
2answers
91 views

Can animals also get Down syndrome?

I heard that animals cannot get Down syndrome or trisomy. Is that true and why can't they get it? They also have chromosomes.
2
votes
0answers
17 views

What is the evidence that mammals are unable to process excess sodium chloride?

I grew up hearing the mantra excess salt causes heart disease I had a vague understanding that it caused deposits in the body or something. Now that I give it more thought - I come up with three ...
-1
votes
0answers
19 views

What are the advantages of large virions?

The Ebola virions are around 1400 nm long and 80 nm in diameter. However, as a RNA virus, its genome is not large, of around 19k. In comparison, Rhabdoviridae are 180nm long and 75nm in diameter, and ...
-2
votes
1answer
27 views

What is the difference of function between palisade and spongy layers of leaf? [closed]

I was just wondering what is the difference between palisade and spongy layers of leaf?
0
votes
0answers
17 views

Telemetry error in Habitat Selection studies

I am using data sets from several researchers with telemetry data, in order to conduct habitat selection studies. However, I don't have the information regarding telemetry error, and I want to use ...
0
votes
0answers
13 views

Difference in associated SNPs in GWAS

I noticed that when GWAS studies are being replicated, some SNPs near a gene known to cause a trait are enriched in frequency in those with the trait. However, among the different studies, the most ...
0
votes
1answer
30 views

Quantity of toxin release by pathogen in host

I came across these lines from this paper: Pathogenic microbes exert a broader sphere of influence by releasing a bolus of toxin that can act upon many cells within a given tissue and/or diffuse ...
0
votes
1answer
50 views

What does a climax community lead to?

Seral communities modify the environmental conditions in such a way that these are less favourable for itself and more favourable for the next community. Each community acts to end itself. If the ...
2
votes
0answers
84 views

What is the another use of de Bruijn graphs in bioinformatics except DNA assembly? [closed]

I implemented own generic de Bruijn graph, which I use for DNA assembly (alphabet: A, C, G, T). I try to find purpose of de Bruijn graph for another bioinformatics problems, if some exists. I want use/...
1
vote
1answer
85 views

What is the mass of an E.coli cell?

I'm trying to get into Biology, reading introductory texts. A discussion on E.Coli estimates the mass of the cell from $$density =1g/mL=1g/cm^3$$ and $$volume=1µm^3$$ From this I get $$ mass=density × ...
0
votes
0answers
14 views

How does RCSB determine the origin of the Cartesian coordinate system utilized in all PDB files

When perusing through the text version of a PDB file, I noticed in records that begin with "ATOM," there are x, y, and z coordinates for these atoms. How is the origin of each molecule's Cartesian ...
0
votes
0answers
31 views

What is the rationale behind IgM being the default antibody?

I know that the$\ C _\mu $ gene appears first in line for class switching and hence the IgM is the default antibody. But what is the rationale for it being so? There must be some advantage (...
1
vote
2answers
41 views

From 46 human chromosomes, is each one from a single parent?

Humans have 23 pairs of chromosomes. Each chromosome in pair is homologous to another one in pair. Does this imply, that the entire chromosome in any cell is obtained from only one parent? I mean ...
0
votes
1answer
29 views

Does common X-like picture represent one doubled chromosome or two homologous chromosomes?

What is on common X-like picture of chromosome? Here is the image from Wikipedia: Are (for example) lower petals homologous to each other? If yes, then why (1) ...
7
votes
2answers
85 views

What really is color and how do we perceive it?

How do our brains actually transform the information that our cones receive into the different colors that we can see and imagine? Sorry if this question is low quality, I just couldn't find a good ...
0
votes
1answer
8 views

Since RNA viruses and retroviruses all have high mutation rates, why do only a few viruses have the virtue of variability?

We have been taught that it's difficult to make vaccines to influenza, HIV and HCV because they lack the proofreading mechanism, hence have high mutation rates. But most RNA viruses and retroviruses ...
2
votes
0answers
8 views

Do all +ssRNA viruses have similar structures and life cycles?

Take HCV for example. HCV doesn't package any enzymes in it's virions. When it infects a cell, it first translates its RNA genome. It's RdRp is synthesized with other non-structural proteins. Then its ...
0
votes
0answers
15 views

Why does the oral epithelium break and fall off when it is burned?

When you gobble up food that is too hot, you may damage the inside of your mouth cavity. More precisely speaking, I believe the mucous membrane lining the surface of your mouth cavity is damaged. ...
0
votes
1answer
10 views

How would one determine if an up regulation of one protein leads to an over expression of another?

Again, I'm new to biology and have a bunch of questions. Does it depend on the proteins involved? OR are there basic co expression procedures one could implement to determine exactly how much one ...
3
votes
1answer
22 views

How many cell membranes are oxygen and carbon dioxide diffuse through in the lungs?

In the lungs, oxygen and carbon dioxide pass through cell membranes by diffusion. Which row is correct? The correct answer is D, but I think it should be B. I can only think about three layers as ...
1
vote
1answer
20 views

Which diagram correctly describe an effect of tar entering lungs?

Which flow diagram correctly describes the effect of tar entering lungs? Tar is a cause of Chronic obstructive pulmonary disease (COPD) which includes both chronic bronchitis and emphysema and it ...
1
vote
3answers
51 views

Why do people remove excess solution after they put on a coverslip?

Today, my classmate and I stained a slide of cheek cells. After we put on a coverslip, our teacher said that we are supposed to remove excess solution using a tissue. Why should we do this? I am so ...
1
vote
0answers
11 views

Is any of this a Fern? [migrated]

A couple of months ago I planted some silver fern spores. For a while nothing happened, but now I have 2 different types of plants growing in my pot, and I'm not sure if I should be removing one of ...
2
votes
1answer
63 views

Electron balance for biomass synthesis: is my professor right?

I'm studying for my exam and I came across these notes written by the professor himself. He's talking about the general reaction of biomass production in a bioreactor: $$\ce{C6H12O6 + NH4+ + O2 -> ...
19
votes
3answers
3k views

Why are vaccines for polio taken orally while vaccines for TB needs to be injected?

My thoughts are that maybe the TB antigens necessary to produce an immune response are proteins; therefore they can be digested in the stomach and small intestine. But I may be wrong though. I am ...
10
votes
1answer
739 views

Species Identification: Red velvety insect, India

Description: Location: India These insects came out just after overnight rain. They were all over the place. Their body looks like velvet. Are these insects poisonous?
0
votes
1answer
22 views

Using exogenous genes to reduce the set of essential amino acids?

Various organisms have sets of essential amino acids that they cannot synthesize themselves, but rather that they must obtain from food. Humans have 9 of these amino acids. However, obviously certain ...
0
votes
1answer
54 views

How do cells age and die if they are dividing into new cells?

If cells in our body keep on dividing into new cells how do they ever grow old? The only cells to grow old would be defunct cells or those who won't divide into new cells like nerve cells. What am I ...
4
votes
1answer
35 views

Species Identification: large shiny black beetle, Detroit USA

What sort of beetle is this? I live in a suburb of Detroit and found a whole bunch of these living under my lawn when I was replacing a section of it. I'm assuming these are also the source of the ...
2
votes
0answers
44 views

Species Identification: Small white maggot/larvae, Missouri USA

I'll try to give as much information as I can, because I don't know which information will be more important. We woke up this morning to these little white worm/larvae in the house. We are located in ...
0
votes
1answer
28 views

How is oxytocin produced?

Is oxytocin (or other peptide hormones) produced from a gene through translation, or is it made some other way?
4
votes
2answers
349 views

How do traits with no negative effects get “weeded out” via evolution?

If only those who are most fit to reproduce are the ones reproducing the most, it makes sense that traits that prevent one from reproducing would eventually disappear from a population. But what ...
1
vote
0answers
13 views

Hybrid vs introgression zone in natural populations

In the book An Introduction to Molecular Ecology, the authors are saying that introgression is the diffusion of alleles from one population or species into another as a result of interbreeding ...
2
votes
1answer
61 views

Species Identification: Bulbous root on plant, Southern California, USA

In Southern California, I was pulling out some roots and grasses and weeds in our backyard, and I noticed something weird. It appeared like there was a grape-sized bulb of something connected to one ...
2
votes
0answers
14 views

H is the set of all possible Diplotypes that are consistent with genotype data

I am new to Biology.SX. I have a statistics background, and have almost zero knowledge in genetics. I am trying to understand some things related to genetics in a certain paper of biostatistics. ...
1
vote
0answers
18 views

Do cortical cells in root have higher water potential than endodermal cell solution?Or is it the other way round?

Well, water normally passes from root hair cells to cortex to endodermis, and from there to the xylem vessels. All of this occurs down the water potential gradient by apoplastic or symplastic pathway ...
2
votes
2answers
47 views

Why is oxygen and CO2 measured in pressure instead of mmoles/L like other ions?

Na, K, Cl...All measured in mmol/L in plasma. Why is oxygen and CO2 measured in pressure (mmHg)? (I guess it has something to do with them being bound to RBC but I don't know why the difference).
1
vote
1answer
53 views

Output of clustalo on (1.2.1) on ubuntu 14.04

I am trying to align the following 8 sequences using clustalo on ubuntu terminal using the following command. But I am not getting the right output. ...

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