This tag is for questions about the general biological features of human beings (as opposed to the biology of non-humans).

learn more… | top users | synonyms

1
vote
1answer
48 views

Which are the last cells of the human body to die?

When somebody dies, which are the last surviving cells of his/her body? Those of hair, nails, or some other obscure but resilient cells? Shedding light on why and how they are so vital might boost ...
0
votes
0answers
28 views

If your atlas is out of alignment, will the rest of your spine be out as well?

I just found out about this association called Nucca. Basically, they are a chiropractic association - their whole idea is that if your atlas is out of alignment, then the rest of your spine is also ...
-2
votes
0answers
13 views

Could humans metabolize gasoline? [duplicate]

Gasoline is mostly made of organic compounds/fats/oils. Food is also made mostly of similar organic compounds. Therefore, would humans be able to metabolize gasoline, or some of its components, for ...
1
vote
2answers
440 views

Can excessive carbonated drink consumption lead to elevated red blood cell levels?

I've recently had a blood test and the results displayed elevated levels of erythrocytes as well as hemoglobin. (As a result my hematocrit levels were also above average) At my workplace there is a ...
-1
votes
0answers
17 views

peritoneal dialysis Vs Hemodialysis?

Their are basically two types of dialysis: 1.peritoneal dialysis 2.hemodialysis, My Question is Why the peritoneal dialysis needs to be carried out on everyday BUT hemodialysis is carried out on only ...
0
votes
0answers
10 views

Is there any range for Aortic Valve Gradient?

I understand aortic valve gradient is pressure on the value (measured in mmHg). What I would like to know is if there has been any research that identified a minimum and maximum pressure value as the ...
2
votes
1answer
1k views

Why does air from the nasal cavity not go into the oesophagus?

When we ingest food, the epiglottis covers the trachea and the uvula covers the nasal passage. But what happens when we breathe? Why does the air go into our trachea and not the oesophagus?
2
votes
1answer
2k views

Does a woman contain all the genes needed to make a man?

I know the answer of inverse is at here, but how about this question? I also read this question, can I imply to human that a woman also contain all the genes needed to make a man? Edit: ok , I ...
4
votes
1answer
262 views

How significant is the genetic component of homosexual behaviour?

From some basic googling, I found that nobody has ever proven that people are born gay and that environment plays a great part in homosexuality. I wish to know if there is a genetic component to ...
4
votes
1answer
938 views

How are arms different than legs?

Ok, this is a bit of a tangent question, but it came up yesterday and I didn't know the answer: How are arms and legs defined physiologically? For example, we say humans have two arms and two legs, ...
-1
votes
2answers
86 views

What makes something food?

From my (limited) understanding, animals get energy from food by breaking chemical bonds between molecules. There's a lot of water here [citation needed], so it seems like natural selection would ...
2
votes
1answer
64 views

Why cold water results in cough [closed]

I have a pretty simple question which always kept me intriguing since childhood and I couldn't find its precise answer yet. Why do we cough by cold water. Recently I had flu and found very strange ...
1
vote
0answers
33 views

What happens to the human brain when unconscious?

What part of the brain gets affected and does it harm the brain? Thank you I just needed some extra info for a video I'm making.
3
votes
1answer
852 views

What are hot spots on human body?

Recently I have just discovered that a certain amount of the mobile phone frequency can be absorbed by human tissues. For example, this is the SAR info of iPhone 4s: Head: 1.180 W/kg 1 g Body: ...
-1
votes
0answers
8 views

Cell Lines in Cancer Biology [closed]

Where could I find information regarding cell lines such as A549, MDA-MB 468, MCF-7, Hela etc. with respect to their origin, usage, mechanism of action, specific receptors, advantages and ...
3
votes
0answers
35 views

What happens to the brain during sleep versus unconsciousness?

How does being unconsciousness differ from being asleep and whether it causes breaks in consciousness?
3
votes
1answer
91 views

How two genomes adopt when cell goes to recipient's body from donor's body?

We often give blood to another following the blood giving compatibility chart. Heart transplant and similar transplants also brings one's cell to another's body. My curiosity is, when a cell goes to ...
0
votes
0answers
37 views

Is human regeneration possible? [closed]

A lizard has the ability to regenerate its tail. Is it possible by genetics to use this property on a human who is handicapped to regenerate their hand? Has this ever been tried in the past? Will the ...
6
votes
1answer
3k views

Why don't we have hair on palms?

We have hair all over the body except palms. What is the biological reason behind this? Thanks
0
votes
1answer
22 views

Does mechanotransduction of cells play a role in the biocompatibility of titanium?

What exactly is mechanotransduction as the information varies between sources. Some sources indicate that mechanotransduction is the underlying principle where cells pull on the surface they grow on ...
5
votes
1answer
365 views

Getting goosebumps at will

I can get goosebumps at will, regardless of the environment. Its mostly visible on my arms, and I can feel it on my head. It requires some level of concentration to achieve this. My questions are : ...
3
votes
1answer
45 views

Do animals other than humans dislike food sources that others seem to like?

Humans (especially children...) seem to dislike certain foods or drinks, that other humans seem to like. Common examples are coffee, french cheeses, milk, fish and cabbage. Are there examples of ...
0
votes
1answer
46 views

Evolution to store limited Fat

Why are our bodies not evolved to store only limited amounts of fat, which won't kill us with all diseases associated with obesity? Wouldn't obese people die faster and clean the gene pool for people ...
3
votes
2answers
80 views

Does sweat contain DNA information?

I was reading this article : Perspiration The first question which came to my mind after reading the composition of sweat was whether it contains any information about the DNA or not? I haven't had ...
6
votes
0answers
58 views

Can a Turner syndrome patient develop male characteristics artificially?

From an answer to the question Can stem cells from male convert to cells of female-only organs, and vice versa? Y chromosome is the sex determining chromosome with SRY gene that determines testes ...
3
votes
3answers
5k views

If the top epidermal layer is burned away, what is it replaced with?

If the squamous (top) layer of epidermis, or skin, is burned or damaged in another way, will it then be replaced by the next layer of below? Also, from where does the basal membrane originate? Does ...
0
votes
0answers
10 views

Cellular aspartate level?

I know that aspartate is a product of urea cycle, gluconeogenesis and oxaloacetate. In addition, there are dietary sources such as meat and vegetables. I would like to know what are the other factors ...
0
votes
0answers
51 views

Why is my right hand's thumb on the left side and my left hand's thumb on the right side?

My daughter just asked this question, and I could not provide a thorough answer. My first speculation is that it allows one to manipulate an object using one' both hands simultaneously (if the thumbs ...
5
votes
1answer
2k views

What does vitamin B6 and B12 absorption depend upon?

I'm looking at my question about homocysteine metabolism and am doing a followup inquiry into vitamins B6(Pyroxidine) and B12(Cyanocobalamin). I've found this interesting bit about vitamin B12 and am ...
-1
votes
1answer
48 views

Is it possible to grow a fertilized human egg entirely outside the woman's womb?

Many science-fiction movies show the possibility of growing a newly fertilized human egg entirely outside the womb of the woman. This means that you have to create the exact circumstances for the ...
8
votes
2answers
243 views

Are unilaterally deaf people able to determine where sound comes from?

My question is on people deafened in one ear, but normal hearing in the other. Time and level differences between the two ears are only part of how the human body can localize the source of the ...
12
votes
1answer
19k views

What is the composition of human feces?

Are there any studies or general information on the composition of human feces? I'd specifically like to know the percentage of carbohydrates and amino acids relative to the amount that was ingested ...
10
votes
2answers
1k views

Why do Hot/Cold drinks taste sweeter once returning to room temperature?

Now, I know this is a very bizarre question, and I tried to find a correct exchange for this, but it might relate to biology/science as it being our taste buds and everything. I am so sorry if there ...
0
votes
2answers
53 views

What physical traits are derived from the Neanderthal DNA in human DNA?

Some researches had found that Human DNA has a bit of Neanderthal DNA. So they suggested there would have been crossing between Homo sapiens and Neanderthals. Now the Neanderthal looked a bit ...
1
vote
2answers
56 views

Does night sleep provide more energy-regain than sleep during the day? [closed]

After reading this, I know that sleeping is an universal function, and that basically everything with a brain has the need to sleep. However, I am still confused to what extent it is necessary to ...
14
votes
1answer
948 views

I don't want to know what bacteria is called but if the bacteria from unborn babies have benifits on health? [duplicate]

This question is not the same as the duplicate. I was told that when babies are born they are born with bacteria in their stomach. When a child takes antibiotics are there unique bacteria destroyed ...
0
votes
2answers
71 views

Use of sunlight in biological processes

Sunlight is used by green plants in photosynthesis, but it is also used by animals in the synthesis of Vitamin D. Are there any similarities between the two processes and how is the light energy ...
1
vote
1answer
74 views

Which part of the reflex arc takes the longest time?

If the reflex arc is composed of 4 parts: Activation of sensory receptors, Conduction to and from the CNS, Transmission across the neuromuscular junction & Activation of the muscular contractile ...
1
vote
0answers
17 views

How much yogurt would one have to consume to have a noticeable effect on neurotransmitters [closed]

I read several recent articles that proposed a link between bacteria in our gut and neurotransmitters in our brain. For instance http://www.ncbi.nlm.nih.gov/m/pubmed/24997036/ I am curious how much ...
13
votes
3answers
463 views

How does a person get AIDS?

I am inquisitive to know about how a person contracts AIDS. Among the common masses it's still the belief that having sex with multiple partners causes the disease but that is not the case when read ...
1
vote
0answers
18 views

How do I “reinoculate” a petri dish with new bacteria?

Hypothetical question, intended to find a general procedure rather than case-specific recommendations: I have a petri dish full of growth medium with a large population of gram-negative, anaerobic ...
1
vote
0answers
45 views

Why is a wound much more painful when damp?

Why is a wound much more painful when damp? This is a very strange phenomenon. For example: I have a little wound, not painful at all. But, when it is just damp, it is much painful.
5
votes
1answer
136 views

How do omega-3 fatty acids reduce cholesterol at the molecular level?

I have heard that omega-3 fatty acids found in fish are a good way to prevent/reduce cholesterol problems. My question is how do omega-3 fatty acids do that: what are they doing on a chemical level ...
0
votes
0answers
12 views

How large are medullary thymic epithelial cells in volume?

I'm looking for a rough average volume of medullary thymic epithelial cells (mTECs/MECs) in humans and mice. It would also help to know how they differ in form (are they spherical, long stretched, ...
6
votes
1answer
70 views

Why is there no symmetry in pigmentation when comparing people north and south of the equator?

If you are at the equator and start moving north, the further you travel, the lighter the skin of the indigenous peoples. Considering that we live on a ball, why do we not find the same traveling ...
0
votes
0answers
12 views

Relationship between Human Sleep Cycles & Sunlight

What is the relationship between the human sleep cycle and Sunlight? Why do humans tend to sleep for longer hours during the night than the day. Since we rely on Artificial lighting during the night ...
2
votes
0answers
43 views

Are all the atoms in your body replaced with others over a 30 year period?

I was reading Creation - Life and How to Make It by Steve Grand. (This is the book that inspired Jeff Bezos to start the AWS initiative. ) In it he makes the following statement: Anyhow, by now I ...
17
votes
2answers
927 views

What is the cause that angina pectoris is felt in your left arm?

When someone has heart problems sometimes they feel pain in their left arm. But why is the left arm painfull?
0
votes
2answers
10 views

Do Class A biosolids count as organic fertiliser?

Does Human Waste, which has been treated at least twice to remove pathogens & remove stink, still count as organic despite it passing the EPA's class A standard? If so, does this mean that ...