0
votes
0answers
2 views

What are most common causes of 'natural' death?

As the title says, what are most dominant causes of 'natural' death nowadays? Meaning when you here that a person died of old age.
8
votes
4answers
9k views

Why is it that cats can jump so high for their size, compared with humans?

My cat is about 1' high at the shoulder, and I am a little over 6', but my cat can easily jump onto something as high as I am. That is 6x it's height. If a cat can do this, then Why can't I jump up ...
0
votes
0answers
5 views

Placental Adherence and Premature Heartbeat

I am studying the placental adherence in premature fetuses i.e. from 22nd week to 38th week of gestational age. About 60% of placental adherences are diagnosed during labour, which increases the risk ...
3
votes
2answers
33 views

What is the definition of a mutation?

There are two alleles that determine the sensitivity of a person to Coumadin (a medicine for blood thinners used to treat a stroke etc). Sometimes you encounter the terminology that one has a mutation ...
0
votes
0answers
11 views

Does the source of caffeine affect the biological impact?

I've recently decided to give up my morning coffee in lieu of a caffeine pill. Both are around 200mg (my Tim Horton's XL 4x4 was 240 mg of caffeine) of caffeine. We were talking about the various ...
0
votes
0answers
24 views

Sexing fish from a tissue sample

How can you tell the gender of a fish from a tissue or blood sample and what equipment do you need (how much magnification in a microscope)? A bit more info: I am a member of a local fish club, we ...
0
votes
1answer
26 views

How and why do skin tags develop?

WebMD writes: Skin tags are small, soft pieces of skin that stick out on a thin stem. They most often appear on the neck, armpits, upper trunk, and body folds. The cause of skin tags is not known. ...
0
votes
0answers
5 views

concentration of a specific promoter

I want to simulate transcription activation by a given transcription factor (TF) with known kinetics. The binding rate $k_{on}$ is given in $\mu M^{-1} s^{-1} $, describing a bimolecular reaction ...
1
vote
2answers
20 views

How does the mechanism which controls blood pressure in the brain work?

I've heard that the blood pressure in the brain is organised by a special mechanism. What is that and how does it work?
0
votes
0answers
11 views

What is the effect of sodium chloride on head lice?

There are a lot of products that claim to kill lice and eggs. The main ingredient is sodium chloride. How does it work? I wonder if it has something to do with osmotic effects?
13
votes
1answer
112 views

How do burrowing animals get enough oxygen?

Tree borers make a small hole in a tree. At the end of it, they chew on wood to elongate the tunnel. They digest food and grow. All this takes oxygen. The entrance to the tunnel is generally small. ...
-1
votes
0answers
15 views

Can the activity of bacteria be influenced by magnetism?

Some organisms are tuning their direction on a magnetic field. But are bacteria also reacting on magnetic fields and can it be used in health therapie as a kind of 'antibiotic'?
2
votes
1answer
21 views

What is it that specifically kills ALS patients?

ALS is a fatal motor neuron disease, and even though there are many different articles out there on the topic "How does ALS actually kill you?", none of them really delve deep enough into biology to ...
2
votes
1answer
17 views

What physical or mental actions can be picked up by EEGs?

There certainly seem to be a lot of gadgets and gizmos leveraging EEG technologies to the control of devices. This makes me wonder: what intentions/thoughts can be captured by EEG technology, and ...
1
vote
0answers
10 views

Is the efferent arteriole a pathway for filtrate through the nephron ?

I am studying the urinary system. I have to identify what part of the nephron is not a pathway for filtrate. I believed the collecting duct is not a pathway for filtrate because once the filtrate ...
5
votes
0answers
162 views

How many ATP are formed?

What is the number of ATP molecules formed during the photosynthetic processes which consume 8 molecules of $\text{H}_2\text{O}$ due to noncyclic electron transport and subsequent ...
2
votes
1answer
61 views

Good pipetting technique?

Good pipetting technique is essential for many biologists, but it can be hard to get right. When I take 1 µl of liquid using a micropipette, I seem to always take less than 1 µl, and that amount is ...
3
votes
1answer
76 views

Is the DNA different in each type of cell? What DNA is passed to offspring?

Our body contains many different types of cells and each of those cells have their own DNA (correct me if wrong) like skin cells their own DNA that makes them skin cells instead of muscle cells. So ...
0
votes
1answer
41 views

What causes swelling after impact?

Why does the head swell after getting hit by something hard? What is the liquid that forms after impact?
0
votes
0answers
104 views

Why did multicellular organisms evolve when a single cell can survive on its own? [duplicate]

Since unicellular organisms can survive, why would there be evolution of multicellular organisms?
2
votes
1answer
38 views

What do proton pump inhibitors do?

I know that sodium azide and 2,4-DNPH inhibit proton pumps. The azide is called an inhibitor and 2,4-DNP is called uncoupler. I want to know what's the difference between the mechanisms of action of ...
2
votes
2answers
43 views

Crossing over and exon shuffling?

Campbell Biology 10e, in discussing the functions of introns, writes: The presence of introns in a gene may facilitate the evolution of new and potentially beneficial proteins as a result of a ...
1
vote
1answer
24 views

amount of tRNA and its extra arm

How much of the total RNAs is tRNA? Some say 15% and some 20%. Those percentages came from my different teachers. Which is correct? And what are the functions of the extra arm (variable loop) of tRNA? ...
2
votes
0answers
13 views

Do primate RGCs have overlapping receptive fields?

According to this link, http://hubel.med.harvard.edu/book/b10.htm retinal ganglion cells (RGCs) receive input from overlapping receptive fields (RFs). This is also an idea used in convolutional ...
1
vote
0answers
15 views

Can the human body switch to a “starvation” mode? [migrated]

I've heard on multiple occasions from less than credible sources that dieting by eating less (usually implemented by skipping meals, not smaller meals) will cause the human body to enter some sort of ...
6
votes
1answer
68 views

Primary Productivity of Oceans

80% of the world's photosynthesis takes place in the ocean. Despite this, oceans are also said to have low productivity - they cover 75% of the earth's surface, but out of the annual 170 billion ...
0
votes
0answers
28 views

Why do denatured proteins tend to be less soluble than the native protein?

Why do denatured proteins tend to be less soluble than the native protein? In terms of hydrophobic effects, could anyone explain this phenomenon for me?
2
votes
1answer
25 views

Do only one or both pairs of homologous chromatids exchange genetic material during the process of crossing over?

To be specific: Assume chromosomes A and B are homologous. They've both replicated into A1, A2 and B1, B2 and have formed a tetrad at the equator (synapsis). Most textbooks show either A1 and B1 OR A2 ...
2
votes
0answers
12 views

How would one identify cellular transcription factors associated with a viral protein in a treated cell line?

I've been working as the computer guy for a microbiology lab for the past few months. I've always been interested in bench work, but my wet lab experience is rather limited and thus so is my ...
1
vote
1answer
64 views

Why is heart failure treated as more critical than kidney failure?

The heart pumps the blood to supply tissues and kidney always filters the blood to remove urea,extra water and etc. And all these are vital,so the kidney is as important as heart: and my question is: ...
2
votes
1answer
82 views

In the video, “Inner Life of a Cell”, what's the empty space between the molecules?

In the video, ["Inner Life of a Cell"][1,] there's a lot of empty space between the proteins. Is it just a simplification (i.e. they omit smaller molecules)? If so, what are the smaller molecules ...
0
votes
0answers
7 views

What is the function of the Moderator band?

The moderator band in the right ventricle is a band sorts of muscle which consists of a significant branch of the AV bundle. Does it mean it delivers impulses to the anterior papillary muscle faster? ...
0
votes
0answers
7 views

how to see prefrontal cortex works normally by a test?

Is there a test to see if the Prefrontal cortex of someone works normally? especially a simple test like a questionnaire that you give the individuals to fill out and based on their answer you obtain ...
17
votes
7answers
5k views

Why can't we see in low light if staring long enough?

For me it seems reasonable that if I kept my gaze on a fixed point in a room with low light, a progressively brighter and better picture would appear before my eyes, just like a camera can see in the ...
1
vote
2answers
26 views

Can DNA be denatured at acidic pH?

Some say that DNA is denatured only at basic pH. And some say at both acidic and basic pH. So I want to know clearly why and how if DNA is also denatured by basic pH.
0
votes
0answers
6 views

Energy efficiency of carbohydrate > fat conversion

How efficient is the human body in converting surplus carbohydrate into fat? E.g., if you have 100 calories' worth of carbohydrates at the start of the process, how many calories' worth of fat will ...
0
votes
0answers
22 views

Lifeforms concentrations of the categories of macromolecules, and Lipids

Lifeforms are formed of large, modular, organic molecules called macromolecules, large organic molecules called Lipids, and simpler molecules such as H2O. Macromolecules are commonly grouped into the ...
0
votes
1answer
29 views

Normal cell diffusion in normal organism?

We know, that cancer cell can travel across an organism. Is this ABSOLUTELY impossible for NORMAL cells? For example, is it EXACTLY ZERO probability to find some bone cells inside liver or some skin ...
6
votes
3answers
389 views

What happens if a non-diabetic receives an injection of insulin?

If a person without diabetes or any diabetes-related issues receives an injection of insulin, what happens? Would the blood glucose level drop or does the body naturally compensate for the added ...
3
votes
2answers
1k views

Are these lovebugs?

I used to see these insects frequently in Chennai and Bangalore (South India). I just would like to know if this is a kind of lovebug. The lovebug as mentioned in the Wikipedia page is, however, ...
3
votes
1answer
61 views

Distinguishing Father from Brother

Given the (non-identical) DNA sequences of two men and the knowledge that the second man is either the father, brother, or son of the first man, is the DNA useful in determining which of these three ...
0
votes
0answers
15 views

dihedral angles [migrated]

My guide asked me to measure the dihedral angles of a poly-peptide chain.There are 4 atoms in between two planer surface(2 atoms in each plane).(refer dihedral angles wikipedia) There is a formula for ...
1
vote
2answers
103 views

Blebbistatin effect on vesicles

Blebbistatin is a drug that specifically inhibits the assembly of myosin in the cytoskeleton. What effect would you expect blebbistatin to have on intracellular vesicles? ...
2
votes
1answer
40 views

Are the cells (structures) of deep sea fish different? And can they survive in shallow water?

In the deep oceans the pressure is enormous. But still there are fish living. But are the cells of them different from fish who just live at the surface of waters? For example, are the cells smaller ...
17
votes
3answers
451 views

Why would diffusion be faster across a non-specialised tissue?

The standard protocol for a person experiencing chest pains is to chew a 300mg aspirin tablet, the argument being that chewing rather than swallowing the tablet results in the aspirin entering the ...
0
votes
1answer
23 views

Countercurrent multiplier mechanism

How exactly does the countercurrent multiplier mechanism work in formation of urine in the body? I am unable to find a satisfactory answer to this.
1
vote
1answer
20 views

What separates gene loci?

Introns are sections of noncoding DNA that separate exons within a gene locus. However, between different gene loci, I also would assume there to be noncoding regions of DNA. What are these regions ...
0
votes
1answer
32 views

new DNA sequencing technologies? [closed]

Last year I did my thesis in the field of a new method for DNA analysis. Which I think is very interesting although I cannot seem to find any new methods in this field especially the SMRT sequencing ...
1
vote
1answer
34 views

Why did eukaryotic cells develop? [on hold]

If eukaryotic cells can survive in extreme conditions, then why are their still prokaryotic organisms?
3
votes
1answer
81 views

What causes inhalation during breathing?

I have read here that the two major inhalation muscles are the (1) diaphragm and the (2) external intercostals. Additionally, inhalation can also be caused by (1) expansion of the abdominal cavity, ...

15 30 50 per page