2
votes
2answers
107 views

Do humans have a “dominant” neurotransmitter system/sensitivity within their brain?

I've recently heard a podcast, in which Dr. Helen Fisher suggests that there are "4 broad personality types", and each one is associated with a particular neurotransmitter: The corresponding ...
2
votes
0answers
110 views

Which of the cell types commonly found in mammals has the greatest number of mitochondria?

This is basically a fun question, inspired by this answer on scifi.se. So, which cell type will have the greatest number of mitochondria? Obviously, I am talking about wild type, healthy individuals ...
2
votes
3answers
158 views

What do you see if you look at your own retina with the same eye? (optical feedback)

When you record a video while pointing the viewfinder towards the screen showing a live preview you create optical feedback: video example. An anoalogous effect occurs when you turn your microphone ...
0
votes
1answer
66 views

Regional circulation and Cardiac output? [closed]

I am reading my study materials and think what is the systemic POV here Regional circulation Blood flow within the tissue/organs based on the functional demands of the tissue. E.g. The ...
1
vote
1answer
221 views

How many (taxonomic) families are there?

Approximately, how many families have been identified? I've often often come across figures for the total number of species on Earth. Recently, I found myself wondering about the encompassing ranks ...
0
votes
1answer
11 views

How does Mupirocin affect in staphylococcal infection?

I found this sentence confusing Transitor carriers of staphylococcal infections 70% because of mupirocin i/n. Mupirocin is drug which affects some way. I am not ...
1
vote
1answer
31 views

Staphylococcus AG structure?

I found this statement in my study materials in the section of Staphylococcus The AG structure: protein AG (species specific); polysaccharide AG (serotype specific). I know what is ...
0
votes
0answers
60 views

Identification of a mysterious lifeform, what is this? [duplicate]

For the third time in a row, I found a mysterious life-form inside my house. I live in the Netherlands in the Eindhoven region, in a city called Oss near a forest area. Before I set it free outside, I ...
1
vote
1answer
142 views

Birds and Dinosaurs

This came up in an argument with some friends. I know that birds are direct descendants of dinosaurs, shown pretty clearly through the fossil record. However, is it proper to say that birds are ...
0
votes
1answer
29 views

Characteristics of radius of blood vessel

Which properties do determine the radius of blood vessel? I have these thoughts distension, elasticity, contractility and cross-sectional area of the walls. Is there any other properties?
2
votes
1answer
171 views

Elution of biotinylated RNA

I am using Neutravidin Agarose beads to isolate biotinylated RNA. The thing is, in the manual it says to use 8M Guanidine-HCl, pH 1.5 for elution biotinylated molecules. As far as I know it is a very ...
2
votes
1answer
277 views

Death by exsanguination not painful?

Several places on the internet seem to purport that animal sacrifice is painless because exsanguination causes no pain. That sounds unscientific to me and an attempt to appease culture than than using ...
0
votes
0answers
12 views

To understand synthesis of e-NOS and n-NOS with respect to Ca and calmodulin

I found this sentence in my notes interesting E-NOS and n-NOS are Ca, calmoduline dependant ferments. They are synthesized from in small conc as response to physiological signals which ...
0
votes
0answers
34 views

To understand Nitric oxide, iNOS and Tumour cells

I have this figure about nitric oxide and tumor which is for schematic for me to understand it The figure should probably say that tumour cell is induced by NO or alone to go apoptosis and it ...
6
votes
0answers
145 views

What percentage of the total genetic variance is explained by the $n$ most important loci?

Standard models in population genetics look up at the evolution of few loci which impact fitness. The variance in fitness is determined by the genetic variance and the environmental variance (and the ...
0
votes
2answers
27 views

To understand Second messenger signalling in I/c and E/c

I found this picture in my study materials. I think it is too schematic and ignores the big pictures. I think the thing connected to the hormone is receptor. The second messanger is then connected ...
1
vote
0answers
67 views

Osmosis - occurring in both ways?

So I did a prac to identify the osmotic potential of potato tuber cells. There were 5 test tubes with different concentrations of sucrose (0M,0.25M,0.5M,0.75M,1M); a small slice of potato was placed ...
1
vote
0answers
62 views

How many blood types are there? [duplicate]

In total how many blood types are there? And why do people normally know only 8 of them? (A+, B+ , AB+ and O+ and Rh- counterparts)
2
votes
2answers
140 views

Correlation between muscle size and absolute strength

Is there a linear connection between muscle size and the power it can produce? If not, why? And what is the true correlation if any, can it be described with an appropriate function? What other ...
0
votes
1answer
61 views

Can you approximate Cardiac Output by Ohm's law?

I found this sentence from my notes which I cannot understand PR < CO, CO $\uparrow$, PR > CO $\downarrow$ where ...
0
votes
2answers
155 views

How to design an experiment with scent triggered memory recall in humans?

I've recently learned that scents can trigger memory recall in humans, and am thinking about setting up an experiment where I would attempt to induce memory recall through exposure to scents. In ...
1
vote
1answer
66 views

Gene distance and Recombination Frequency: Mechanism

Why is the recombination frequency higher if the genes are farther apart?
3
votes
0answers
51 views

Is a single x-ray photon capable of doing enough damage to the dna of a cell to kill that cell?

Ionizing radiation is damaging to DNA, but is there such a thing as a safe dose below which no DNA damage could occur? I'm not asking about a minimum safe dose overall, just whether or not there's an ...
1
vote
1answer
55 views

In vitro transcription, contamination problem

I am using a RNA which is in vitro transcripted before I started my project. It turned out it is not prepared properly and has DNA contamination. Instead of perform the in vitro transcription again, ...
3
votes
1answer
67 views

Why do hummingbirds build nests with live ferns instead of dead materials?

Hummingbirds prefer to build their nests with spore-bearing ferns, and mosses. This is helpful for the reproduction of the ferns, which are then better able to spread their seeds. But how is this ...
0
votes
0answers
113 views

gamete frequency of recombination

A female genotype, shown as abc / +++ produces 100 meiotic tetrads. Among these, 68 showed no cross over (NCO) events; 20 showed single crossover (SCO1) between a and b; 10 showed single ...
1
vote
1answer
53 views

Calculating photosynthetic efficiency

While calculating photosynthetic efficiency, do we take into account the Gross Primary Production or the Net Primary Production ?
3
votes
0answers
64 views

How do duplicate brain regions (ex: left/right amygdaloid body) operate together?

I frequently hear talk about parts of the brain like "Amygdala" or "Hypothalamus", so I looked them up in an app called "essential anatomy". What I see is that there's mirror symmetry, and most of ...
1
vote
1answer
76 views

Is end-systolic volume (ESV) the same as residual volume?

I am reading this site and my study materials. The end-systolic volume (ESV), 50-60 ml, is the volume of blood found in ventricles after systole and contraction of ventricles. I think ESV is the same ...
3
votes
3answers
66 views

Can 'hardware' thermalization explain memory decay?

Often we are able to memorize very precise bits of information (exact addresses, birthdays of inlaws, number of dirty socks under the bed), but over time our recollection tends to become fuzzy. We no ...
6
votes
2answers
126 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
141 views

Can diploidy evolve in absence of sexual reproduction?

Theoretical question Can diploidy (or polyploidy) evolve from a haploid lineage in the absence of sexual reproduction ? For what theoretical reason? How can such evolution take place? Empirical ...
-1
votes
1answer
73 views

Can nature create codes and specified complexity? [closed]

Is there an example of nature creating codes or specified complexity? It is said by Creationists that codes can only come from minds, and since DNA has a code, it was created by a mind. Is this true? ...
0
votes
1answer
38 views

An over-simplified model of cell division and its relation to stem cells

I am a mathematician, and I decided to try to model cell division with math and see what conclusions came out of it. I had some questions concerning stem cells that came up in the model. In an ...
1
vote
1answer
43 views

RNA integrity and RNA fragmentation

After RNA isolation and before following experiments, I know that RNA quality so called RNA integrity is so important. So why there is a RNA fragmentation kit? Do we need RNA intact or fragmented? ...
1
vote
1answer
54 views

Dilution question about RNA

I have a basic and probably silly question. I am isolating RNA with TRIzol. I have performed the basic steps and dissolved the pellet in 50 uL water. I ve measured the concentration and it was 3313 ...
0
votes
0answers
17 views

What are the main parameters for systemic circulation?

I have in my notes that main parameters for systemic circulation are ejected blood per minute central venous pressure (in the right atrium) work done by the heart something else What can this ...
-1
votes
2answers
261 views

Can you answer Ray Comfort's question on Biological Evolution? [closed]

https://www.youtube.com/watch?v=U0u3-2CGOMQ There's this video on Youtube about biological Evolution that has gone viral. I'll paste it above for your convenience. To cut to the chase, Ray Comfort ...
0
votes
1answer
43 views

Normal position of Electrical axis only in the III lead?

I found this sentence in my notes which is not exact enough: Electrical axes Excitatory processes have definite direction and magnitude and could therefore be represented as vectors. At ...
0
votes
0answers
43 views

ADH Synthesis in Supraoptic and Paraventricular Nuclei of the Hypothalamus

I have this sentence in my notes: Neurons paraventricularis and supraorbitus check the situation and secrete ADH in the nuclei, which by axonal transport → neurohypophysis, where storage take ...
4
votes
2answers
205 views

Why aren't we ambidextrous?

It seems so simple that if my brain can tell my right hand to do something, then it should be able to tell equally well to the left ? This seems like a pretty major evolutionary advantage. Why haven't ...
0
votes
0answers
30 views

How do you amplify a specific AFLP marker?

I'm trying to clone a specific AFLP marker out of Medicago truncatula. I know the selective bases I need for the end of the primers. My problem is that all the AFLP cloning kits I have found are ...
0
votes
0answers
56 views

Analytical skill: Identify possible predator from grotesque collection of desiccated animal carcasses

Not sure this may be the right site for the question. Background: A resident of central india, parts of the house & annexe are a century old. The house is surrounded by a near copse - may be ...
0
votes
1answer
60 views

How does a smoker's pleasure work?

I smoke. For some reason, I've always had this idea that the pleasure of smoking works more or less like this: from the lungs, the nicotine reaches the blood, with which it travels to the brain, and ...
0
votes
1answer
49 views

Physiology of skin and leather: why do salt borders occur?

I discussed a leather store about the white border aka salt border on leather shoes. They said that it is due to inner features of leather and you could try to add some fat/cream to push it back ...
-1
votes
1answer
57 views

Can a certain part of human dna can be replaced with other animals dna?

Human DNA consists of adenine, thymine, guanine and cytosine. Can thymine of other animal can be placed with humans thymine?
0
votes
1answer
54 views

Difficulty in developing certain vaccines

I have a college level background in Biology, say at the level of Campbell. I am very curious to know why it's extremely difficult to develop vaccines for certain diseases. Two cases which I am really ...
4
votes
3answers
411 views

Are humans the only animal that requires “clean water”?

I've seen a number of animals - dogs, cats, squirrels, ducks and geese, etc drink from puddles, some of them were muddy, others had green flora growing under water. Same goes for lakes and rivers. A ...
1
vote
0answers
30 views

Referencing the homologous chromosomes

There exist a co-ordinate system from chromosomes like "12p11.3". In this system, first integer range from 1 to 23 i.e it takes homologous chromosomes as a pair. If we want to distinguish among ...
4
votes
1answer
106 views

What constitutes the determination of a normal blood glucose level?

Several on-line resources (e.g. MedlinePlus) suggest: Normal range for non-diabetic people who are fasting should range between: 70 and 100 milligrams per deciliter (mg/dL) Non-diabetic people who ...

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