3
votes
0answers
22 views

Blood as newtonian flow and Poiseuille law [closed]

For a prep exam: A healtly pacient has a carotid with the following characteristics: intern ratio: 𝑅= 2.8 mm, 𝑃2 = 89 π‘šπ‘šπ»π‘”, 𝑃1 = 90 π‘šπ‘šπ»π‘”, πœ‡blood = 3.5 cp, 𝐿=10.0 cm. Using the ...
1
vote
1answer
29 views

How to define drug-resistant or -sensitive cell line when knowing the IC50 values?

I have got the IC50 data for a drug on different cell lines. How to define if the cell line is sensitive or resistant towards this drug? Could anyone tell me how to define this?
3
votes
1answer
61 views

How do genetic chimeras with different blood types not die?

If a person is a chimera and has two different blood types in his veins, how does he not die? Shouldn't the immune system attack one of the blood types? In 1953 a human chimera was reported in the ...
3
votes
1answer
540 views

What is the minimum air pressure the human body can tolerate if oxygen supply is not an issue?

Disregarding hypoxia, what is the minimum air pressure that the human body can tolerate? (i.e. at what air pressure would the blood start to boil, or skin start to burst, or whatever else might ...
2
votes
1answer
18 views

Which is the guideline to choose a molecular target to identify vertebrate hosts from arthropod bloodmeals?

There are some molecular targets to identify vertebrate hosts from arthropod bloodmeals including the Cyt b gene and the COI gene. Which are the standards or characteristics that I have to bear in ...
2
votes
1answer
53 views

Are genotypes with the same two alleles equivalent even if the alleles come from different parents?

I am looking at the following question If $m$ alleles may occur at a given locus, how many distinct diploid genotypes are possible at that locus? The obvious answer is that there their is $m$ ...
7
votes
1answer
496 views

Identifying an insect looking like a crumle

Recently a little insect crawled over the carpet. First I did not notice, as its appearance is quite similar to the coloring of the carpet. Then I understood that it is not a rolling crumble, as the ...
1
vote
1answer
30 views

Is the motor cortex identical to the sensorimotor cortex?

As far as I understand, the primary motor cortex (M1) and primary sensorimotor (SM1) are notations for the same cortical area in the brain. Am I right that there is no dedicated motor cortex, and that ...
2
votes
0answers
29 views

Do The Traces Genetic Diseases Remain in families?

I know that there are certain diseases that are predominant on genes. But, is there any sort of surety that if parents are suffering from a disorder then their offspring has to suffer from the same. ...
1
vote
1answer
30 views

Genetic Imprinting and Cell differentiaion

It does not seem possible that these two processes can coexist: 1) Genetic imprinting is the phenomenon where genes are expressed differently depending on the parent of origin: 1a. Methylated ...
6
votes
1answer
28 views

What Goes on in Photosystems at the Molecular/Atomic Level?

In light-harvesting complexes, how is the energy of a photon transferred from one pigment molecule to another? And in reaction-center complexes, how does the primary electron acceptor capture an ...
10
votes
2answers
181 views

Why do we urinate more when we are nervous?

This question is a result of my personal experience... But I guess that is common for many of us. My school timing is 8:00 am to 1:30 pm (usually). During normal school days I typically urinate one ...
2
votes
2answers
2k views

What happens if an IV drip with a saline solution slips out of the vein, but keeps dripping into the body?

A patient has a saline solution IV drip into the vein. They have somehow moved around and the needle has fallen out of the vein, but remained in the body. Nobody has noticed and for a few hours water ...
3
votes
2answers
58 views

How to set threshold in ImageJ for quantifying relative fluorescence?

I have taken images from two different samples that have uptaken EdU during DNA synthesis (S-phase). The experiment setup is to find which condition had uptaken more EdU. Therefore I am detecting EdU ...
5
votes
1answer
366 views

What produces the strong odor of decaying dead animals?

Are there specific chemicals responsible for producing the strong, putrid odor that is present after an animal deceases? Also, how long does this odor last?
0
votes
1answer
17 views

Beta oxidation of saturated fats

In my text book there is an example of a 18 carbon long fat and it says that it can run 8 laps of oxidation. I don't understand why it doesn't run 9? 2 are removed each cycle? Thanks.
3
votes
1answer
54 views

What's the frequency resolution of the human ear?

I was thinking about audio compression (namely mp3), that "filters" out sound that we would not likely hear. The MP3 lossy audio data compression algorithm takes advantage of a perceptual ...
10
votes
3answers
336 views

What's the name of this bird?

This morning I saw a bird that I have never seen before. Since it was quite big, I'm very interested in knowing its name. The bird was quite big, at least 2-3 times of a common blackbird. The wings ...
14
votes
2answers
1k views

What's the difference between male and female?

As long as we only look at humans the differences are clear: males have chromosomes XY, produce sperm and don't get pregnant. Females have chromosomes XX, produce egg cells and bear babies. But when ...
0
votes
0answers
25 views

Why do four spermatids have different genomes?

It's been a while since my last class in genetics, so I've forgot most of it. However, I found myself studying human reproduction and I've the following doubt concerning spermatogenesis: the process ...
0
votes
1answer
25 views

What pattern can be learned from the data of RNA seq counts and HiC matrix? [closed]

I now have some data on the RNA seq counts and related Hi-C matrix of gene segment on a chromosome. My concern is, basically, what can we do with these data so as to establish the connection between ...
3
votes
1answer
50 views

Hardy-Weinberg Color-blind

In a city, 4% of male population have color blindness. How many of the female are (a) color blind carrier, (b) color blind? Suppose the city holds Hardy Weinberg equilibrium. My progress: 4% of male ...
2
votes
1answer
853 views

Why does ear wax taste sour?

Why does ear wax taste sour? I am interested in both the physiochemical mechanisms and the evolutionary reasons behind the sour taste of earwax.
0
votes
0answers
16 views

Question about cytoskeleton coordination

I am trying to study for a biology and I am having some confusion over the following topic. Can anyone help explain/ shed some light on the concepts of Rho family GTPases. Is it true that we have Rho ...
1
vote
0answers
28 views

Compare Proteins - Structural / Sequence parameters

I have been working on algorithms that extract co evolutionary signatures from protein sequence. As a result of my work I got some evolutionary information which possibly explains cotranslational ...
0
votes
0answers
20 views

What are comparative advantage of different NGS platforms?

Sanger and Maxam-Gilbert introduced first two methods to sequence DNA. Sanger's Method had great comparative advantages and led the sequencing projects in its time. As I know, currently we have three ...
0
votes
1answer
34 views

Can we use the HIV antibody test to detect HIV in newborns? [closed]

Adults and elder children can use HIV rapid test to test HIV infection. Can we use the HIV antibody test to detect HIV in newborns too?
9
votes
1answer
266 views

Why gluconeogenesis?

It seems quite pointless to me. Why would I want to use energy to create a molecule that I can then use again for less energy? It seems only to serve as a complete waste of energy to me? Can someone ...
2
votes
5answers
81 views

Which information can be obtained from a list of gene names?

Lets say I only have a list of gene names. I know they are up regulated and I know they are related to cancer. What information can I obtain from having only the names of genes? For example is there ...
11
votes
2answers
154 views

Why reference genome is a reference?

I have heard that a reference genome such as humans is generated by randomly choosing samples from a group of donors. But why do we call the DNA sequence generated as a reference? Why should we ...
1
vote
0answers
18 views

Why is Pilobolus phototropic?

Pilobolus is a fungal genus whose fruiting bodies consist of a stalk ending in a spore mass that is launched via turgor pressure to disperse the spores. The fruiting bodies grow towards light, which ...
7
votes
2answers
170 views

HIV Rapid Tests

The hiv antigens that are used in the oral rapid tests, are they infectious? The tests do not contain any actual virus but I am curious if the antigens themselves could somehow create the virus on ...
2
votes
1answer
28 views

How are ketone bodies used?

While searching for literature on ketone bodies, I can only seem to find how they are synthesized, but not how they are broken down. I'm looking for the series of events with enzyme names and ...
2
votes
1answer
18 views

How is circadian rhythm of gastric acid secretion regulated?

Gastric acid secretion shows a circadian rhythm where acid production in the morning is minimal and it reaches a maximum towards the evening. How is this process regulated?
4
votes
1answer
37 views

How does a change in the potential across a neuron's membrane get turned into a signal that is sent down the axon?

I understand How a signal is propagated down the axon. How the membrane potential of a neuron changes during the course of it's "firing". But I don't understand how physically the change in ...
7
votes
1answer
47 views

Reasons for the HIV-1 epidemic

So, the HIV-1 jump to humans occurred as early as the 1920s, but the AIDS epidemic didn't start until the early 1980s. Some things I don't understand about this: Why the delay? What is needed for a ...
1
vote
1answer
36 views

Why use creatine phosphate?

We use creatine phosphate as an energy storage to resupply ADP with a phosphate group as our muscle cells only contain about 2-5 mM ATP. But why doesn't the muscle cells just keep 20-30 mM ATP instead ...
5
votes
2answers
35 views

Time required for RNA precipitation in ethanol

I precipitated bacterial RNA during 1 hour at -80ΒΊC after depleting rRNA with Ribo-Zero kit. Does more time lead to better results?
1
vote
2answers
26 views

How does the placement of it's motor domain affect the directionality of a motor protein?

I'm going over some of my notes, and I have written down that motor proteins with + cytoskeletal directionality have a reversed schematic representation relative to - directed motor proteins. Then I ...
5
votes
1answer
62 views

Why do apples taste sweeter at the bottom?

Sometimes when eating an apple, I notice that the bottom (blossom) end of the apple has a lot more sweetness and flavour to it, whereas the top half (stem) is often more watery, crispier and feels ...
0
votes
0answers
25 views

Why doesn't the body optimize how many fatty acids it burns?

Ketone bodies are produced due to an excess of fatty acids being burned (accumulation of acetyl-CoA) so my question is: Why doesn't the body simply regulate how many fats it burns so it doesn't have ...
1
vote
1answer
34 views

Do you know of ways that help a plant to produce more flowers?

In Crocus sativus, or saffron crocus, the most commercially important part is stigma of flowers. Each plant produces one flower (so there is more than one plant in this picture) and each flower has ...
2
votes
1answer
23 views

What is the difference between sinew and tendon?

I wonder what the difference between sinew and tendon is. I searched for it but didn't get any clear answer: https://www.quora.com/Whats-the-difference-between-sinew-and-tendon: They are often ...
2
votes
1answer
26 views

NADH shuttles - Why cytosol?

Why is the malate-aspartate and the glycerol-3-phosphate shuttles located in the cytosol and intermembrane space? The krebs cycle happens in the matrix so why wouldn't they push electrons from the ...
4
votes
3answers
303 views

Does a neuron ever generate an action potential without stimuli?

Most accounts I read involving action potentials and synapses and the like tend to focus mostly on the action potential as a mere automatic reaction to another similar event happening upstream. From ...
1
vote
1answer
22 views

How does a microelectrode work?

On Wikipedia, the entire microelectrode page states only the following: A microelectrode is an electrode of very small size, used in electrophysiology for either recording of neural signals or ...
2
votes
1answer
30 views

Atelectasis due to decreased surfactant in lungs

Surfactant is a protein lipid mixture produced by alveolar pneumocytes composed of Dipalmitoyl Phosphatidyl Choline lipid, apoproteins and calcium ions. This surface lines the alveolar epithelium ...
1
vote
1answer
125 views

What is the chemical composition / empirical formula of Herpes Simplex 1?

Viruses such as polio are so well documented that a search for "empirical formula polio" gives you something like ...
4
votes
2answers
67 views

Are all action potentials the same shape and amplitude when graphed with respect to time?

The most common visualization of an action potential is a graph of the difference in membrane potential (y axis) at a particular time (x axis). According to my textbook Cognitive Psychology by E. ...
1
vote
3answers
105 views

Resilience to the neurotoxins of Indian King Cobra

I read on Wikipedia about this: King Cobra - Wikipedia In Thailand, a concoction of alcohol and the ground root of turmeric is ingested, which has been clinically shown to create a strong ...

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