7
votes
2answers
416 views

Help with the Price equation

The Price equation describes mathematically the evolution of a population of units from one generation to the next. $\bar{w}\Delta \bar{z}$ = $Cov (w_i,z_i) $+$ E(w_i\Delta z_i)$ I would like ...
3
votes
1answer
193 views

How do GPCRs transmit a signal across the plasma membrane?

How do G-coupled protein receptors (GPCR) transmit signals through the plasma membrane? Links containing information about this and pictures will be very helpful.
3
votes
3answers
84 views

dsDNA translation

Since DNA is double stranded and each strand is complementary to the other, the codons on each strand will come out to be different after transcription(depending on the reading frame). Does this mean ...
2
votes
2answers
42 views

Do Noroviruses include many families?

Wikipedia says Caliciviridae Family. My notes say that Norovirus includes the following Noroviruses Norwalk-like viruses Caliciviruses Astroviruses and some small gastroenteroviruses which is a ...
1
vote
1answer
93 views

Can Alzheimer's disease be caused by Slow Prion infection?

I found this claim in my study materials with explanation of amyloi plaques, in comparison to CJD (Creutzfeldt-Jakob Disease). Its characteristic are Long doubling time of at least 5.2 days (I ...
-1
votes
2answers
90 views

Why it is rare for person to get infected with two Pathogens?

Why is it rare for a person to have 2 (or more) infectious diseases (for example: Flu & Cold together at the same time)? Although it's rare, it happens when the immune system is weak (e.g when ...
4
votes
1answer
819 views

Why do veins look blue?

I know that veins carry oxygen. Veins look blue because the oxygen-depleted blood in them is blue. Is this true??
1
vote
0answers
37 views

Plateletpheresis for hemophilia

Plateletpheresis is seperation of platelets from whole blood and putting the leukocytes and erythrocytes back into the blood. If the person donating platelets does not have hemophilia than could a ...
0
votes
1answer
37 views

Calculation of water potential

For a mesophyte growing in a moist soil, water potential of its root sap is -3 atm, then how to find the water potential of moist soil and leaf respectively?
1
vote
1answer
81 views

Error in textbook

This must be an error Just as proteins have a polarity defined by the amino and carboxyl termini, oligosaccharides have a polarity defined by their reducing and nonreducing ends. The ...
4
votes
2answers
122 views

A photosynthesizing mouse?

N. Shubin's Your Inner Fish makes the point several times that there is a lot of functional similarity between some seemingly remote gene cousins. If that needed reinforcing we have the spider-goat, ...
1
vote
1answer
41 views

Why can't intermediate filaments be used as tracks by motor proteins?

A motor protein like kinesin-1 cannot use an IF as a track because it lacks polarity. Can someone elaborate on this answer?
10
votes
1answer
204 views

What would be the conduction speed of A-alpha fibers, were they unmyelinated?

It's known (Hursh 1939) that myelinated axons exhibit the behavior $v = 6d$, where $v$ is the propagation speed [m/s] and $d$ is the axon diameter [μm]. A related relation for unmyelinated axons is ...
2
votes
1answer
28 views

Can Rubella virus pass into brain stem?

B19 virus (about 20 nm) can; which I think is partially because of its small size; not sure of genomics has something to do with the passing. Rubella's (also called German measles) size is then again ...
8
votes
1answer
230 views

Identify a bird

I have taken this picture of a bird in university zoo in Tel Aviv. It was approximately 25 cm high and seemed to be a flightless species. Can somebody help me identify it?
2
votes
1answer
765 views

Properties of Satellite Chromosomes

I have some questions regarding Satellite chromsomes which could not be resolved by a google search. Does the satellite consist of telomeric sequences ? If not, What is the function of a satellite ? ...
3
votes
4answers
1k views

Refutation of Darwin's Random Evolution Theory [closed]

I saw this refutation online of Darwin's Random Evolution Theory and cannot see any holes with the logic. Can anyone crack this simple refutation? Refutation of the Theory of Random Evolution ...
6
votes
2answers
132 views

What type of force holds my body rigid & doesn't make it collapse?

My query is that as atoms & its molecules have inter & intra molecular forces,like that only what type of force keeps the cells bonded to each other & prevent it from collapsing ever ...
3
votes
2answers
356 views

How do bats distinguish between day and night?

How do bats distinguish between day and night? Do they hunt at night - if yes, how they know that? Are they afraid of sunlight?
3
votes
1answer
137 views

Pharmacology Half Life Calculation

I'm really stuck on this question. I'm being asked to find the half life of a drug. The Vd is 50L/kg. The clearance is 0.1 L/hr/kg. The patient weighs 70 kg. Equation is: T1/2 (halflife) = 0.693 * ...
7
votes
2answers
1k views

How are babies born without a brain?

In the United States, anencephaly occurs in about 1 out of every 10,000 births. There are several forms of this condition, wherein the forebrain is absent. The forebrain is host to most of the higher ...
3
votes
0answers
125 views

Human female chest model or data representation?

I am looking for professionally used representation of female chest (I know how it sounds ;). Generally - a model comprehensive enough to effectively represent human chest, with focus on breasts. ...
1
vote
1answer
68 views

downloading a reference genome for alignment

I am currently working through the code example on the MATLAB website. It requires me to download the reference genome of Arabidopsis thaliana (thale cress) so I can use BowTie2 to align the Chip-Seq ...
2
votes
1answer
103 views

Why are some scorpion species fluorescent under UV light?

It's known for some scorpion species such as Pandinus imperator, Heterometrus Petersii etc. to be shining under UV light. That makes them easier to capture and collect by humans. Is there any ...
2
votes
1answer
47 views

Why are dreams sometimes remembered and sometimes forgotten?

Why is it that sometimes, when we wake up, we are able to remember what we were just dreaming, but sometimes we don't remember any of it?
1
vote
1answer
30 views

Property of E.coli harboring F element

From Genetics by Ursula Goodenough E.coli harboring an F element are endowed with a number of phenotypic traits : 1.They are sensitive to infection by ssRNA phages and certain ssDNA phages. ...
2
votes
1answer
31 views

How many areas are there in Brodmann map?

I read Wikipedia claiming 52. I heard that this can be extended to 54. I see there is no limit of having more areas - just better understanding of the neuroblast migration and fibroblast too, ...
0
votes
2answers
151 views

Blood Type Compatibility [closed]

It should be that because O+ blood(which is my blood type) has all antibodies but no antigens that all other blood types including O- would be incompatible making O not a universal donor so why is O ...
3
votes
1answer
79 views

How do Kangaroo mothers deliver the correct kind of milk to the correct joey?

Mother kangaroos are able to rear multiple joeys (young kangaroos) at different stages of development at the same time. According to Wikipedia, "the mother is able to produce two different kinds of ...
2
votes
1answer
105 views

Are Night Parrots (Pezoporus occidentalis) really extinct?

This incredibly rare animal has been reported to be extinct since 1990, however several cases has been raised that night parrot was spotted in the areas of Australia. What is the cause of their ...
0
votes
1answer
30 views

Can systemic venous congestion caused by tumor?

I am thinking, if 1) little compressed superior caval vena and 2) some vein compression by tumor, can cause systemic venous congestion. I think this is only in rare occasions. However, the question ...
6
votes
2answers
4k views

When designing primers how important is the GC clamp?

I'm designing a set of primers and reading about the principles of primer design one of which is: GC Clamp: The presence of G or C bases within the last five bases from the 3' end of primers (GC ...
2
votes
1answer
95 views

How does the MMR vaccine affect lymph nodes in preventing measles?

I am trying to understand this statement about the Measles part of the MMR (Mumps, Measles and Rubella) vaccine Measles prevention: MMR (AB protect during primary and secondary viremia) Measles ...
3
votes
4answers
1k views

Bad Eyesight and Evolution

Why do many humans have bad eyesight, such as near-sightedness, which hampers performance in a wide variety of tasks? Shouldn't there be evolutionary pressure towards better eyesight?
14
votes
1answer
1k views

What do viruses do during incubation period?

For example, there is an incubation period of around 1 to 3 days for common cold, and that of AIDS can range over to decades. What do viruses do actually do during the incubation period? What ...
1
vote
1answer
63 views

Conclusions from hybridization results

A double stranded DNA was denatured in a mixture that included mRNA from a gene in the segment. The mixture was then cooled to promote RNA and DNA hybridization. The following figure the results. ...
1
vote
1answer
64 views

What does “tumour budding” mean?

tumour budding, lymphocytic infiltration and resection margins are established factors that influence the outcome of colorectal cancer (1) In this context what does "tumour budding" mean? Reference ...
2
votes
1answer
116 views

Steps to confirm if predicted miRNA is good or bad

I aligned all miRNAs available to the supercontigs of a particular genome with certain parameters (e value of 0.01 and a word match of atleast 7 as suggested in this paper). I have also isolated the ...
1
vote
1answer
51 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
164 views

Breathing under water

Why can fish breathe under water but land mammals can't? How can fish extract oxygen straight from water but humans can't?
7
votes
1answer
109 views

How do animals perform detailed active camouflage?

We often see videos of octopuses and chameleons changing their color to suit their surroundings. If it was a simple color change from white to red, it'd be understandable, but some of these animals ...
5
votes
1answer
86 views

Selective Androgen Receptor Agonist

I'm looking for an inducer that strongly activates the androgen receptor, but not the glucocorticoid receptor that is not DEA regulated. I know that SARMS (Selective Androgen Receptor Modulators) are ...
3
votes
1answer
156 views

What happens if someone with mutations to alcohol dehydrogenase (ADH) drinks alcohol?

ethanol then doesn't get converted to acetaldehyde. in fact, could someone KO'ed for ADH be resistant to methanol poisoning?
0
votes
1answer
622 views

Genes, chromosomes, base pairs and the 23 pairs

OK so I'm a bit confused. Does a chromosome consist of genes and do genes consist of DNA? What about the 23 pairs in sexual reproduction? I can't remember what the pairs consist of
1
vote
1answer
31 views

Relation between respiration and concentration of citric acid

A and B are 2 reactions. If there is an excess availability of citrate, then which of the above reactions will prevail? I know that citric acid is formed when oxaloacetic acid reacts with acetyl ...
0
votes
1answer
41 views

Feedback affecting myocyte metabolism in humans

I understand that there are several reserves available to muscle that can be tapped for ATP, and that each reserve is being used to some degree at all times. Are these reaction rates purely due to ...
2
votes
1answer
58 views

What is inside IDL (intermediate density lipoproteïn)?

I am studying about the endogene lipidcycle in the human body and I know that VLDL (very low density lipoproteïn) is made in the liver and that it contains triglycerides and cholesterol from your food ...
3
votes
1answer
80 views

Biological advantage of electric synapses

Electric synapses are synapses that do not process information but simply foward one action potential from one neuron to the next. There are no neurotransmitters, no inhibitory and exitatory ...
3
votes
2answers
520 views

Initial population when i count backwards?

My question is dealing with how many ancestors it took to produce me: --> to produce me it took 2 people (my parents) = ($2^1$) people = 2 --> one generation further included = ($2^1 + 2^2$) people ...
3
votes
1answer
343 views

What is “bacto” peptone?

Standard recipes for yeast medium often include "bacto-peptone". Is this the same as bacteriological peptone? Is there an authoritative source that spells it out?

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