Questions tagged [death]
A state in which an organism or a cellular system, as defined by its full set of functionality, ceases to exist (i.e., most of the functions are irreversibly lost).
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In atherosclerosis, why do apoptosed macrophages stay on the endothelium?
In atherosclerosis, the following process happens:
Lipid deposits of LDL-cholesterol happen on the endothelium
They triggers an inflammatory reaction of the endothelium: macrophages circulating in ...
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Are there human genes that make a cell die when they undergo copy-number alterations?
I am trying to understand if there are known genes in the human genome where copy-number should be stable at a diploid level for the carrier cell to live.
I.e., are there lethal deletions or ...
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Cause of premature death in turtle eggs
Context
I am a hobbyist turtle breeder and I have been keeping and breeding turtles for 15 years (I have hatched turtles in the high hundredths).
Long story short, few years back, my friend and I ...
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What are the different factors involved in ageing?
This is a big edit of the previous question
Thanks to first comments and answers of the previous question, here is a more specific question:
An organism faces ageing. This ageing is linked with ...
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What is the time frame for coagulation of blood cells & the resulting separation of the cells and platelets from the plasma in a dead body?
I have had this subject come up repeatedly in the context of a discussion about death and how it affects the body.
I found this statement, which is typical of the common understanding among non-...
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Differences between comatosed states and brain death
What are the neurological, physical, etc. differences between someone who is in a coma (one that is not medically-induced) and someone who is colloquially deemed "brain dead" (being ...
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Is a corpse more flexible than a living person?
I read that the majority of humans have the muscular-skeletal potential to perform the splits that you see many gymnasts perform. The reason a living person with no flexibility training can not ...
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When is it viable to remove old graves?
Societal considerations aside, when all the remaining relatives of a particular gravesite have all disappeared or forgotten about a certain grave, is it viable/hygienic to remove or repurpose old ...
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Why are victims of Covid19 being wrapped in plastic?
Several articles describe the unique ways Covid-19 patients are being buried.
For example, in this Reuters article about Israel:
These included decontaminating and hermetically wrapping bodies in
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How and when does the regeneration of cells that have died start?
I assume that the replacement of cells that have died (or been removed by any means) doesn't work on a single cell level but starts only when some critical number of cells have died.
My question is: ...
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How are cells that have died replaced by new ones?
I'd like to have a clearer picture how cells that have died are replaced by new ones.
I assume the following:
Normally, when a cell dies it will be replaced by a new one of the same type.
It will be ...
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What kinds of fish tend to have a rapid death after being caught?
I am asking this question because I am trying to make my diet less cruelty-oriented, for this reason this question can be related to trolley problem since I am coping with an ethical problem trying to ...
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Do dead bivalves always float in water?
This 2014 Oct 14 article by Jolene Bouchon avouches:
How do you know if your bivalves are alive? Immediately get rid of anything with broken or damaged shells. Clams and mussels shells should be ...
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Mammal Statistics about Natural Death Versus Being Killed?
Is there data determining what percentage of mammals die a natural death (disease, old age) and what percentage die due to being killed and/or eaten by other mammals?
In watching wildlife ...
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Is there a physiological reason why direct lightning strikes are not lethal for everyone or does it all come down to dumb luck?
Some people who get directly struck by lightning and some more than once (starts at 00:25) survive while others die instantly or later on due to complications/injuries.
Looking at a wiki page for ...
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How do booklice avoid dessication?
I often find booklice (aka psocids) in old paper notes I have in semi-storage. These pages of paper are intentionally left in dry conditions on my desk to avoid damage. However, if the psocids live ...
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Where can I find resources of the biological processes occurring after death of a mammal at various temperatures?
Using google I usually end with results in cell death. I found some layman articles, but that does not help.
My main interest is the brain part.
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What's the decomposition rate of a mammal at -20 Celsius? [closed]
Is there any where to predict it without thawing? In terms of measuring it.
What if the body was immersed in sugar prior to freezing?
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Why exactly does the immune system weaken with age?
Why does the immune system become weaker with age in humans and in some other mammals? Let's try to be more specific than just "everything degrades with age."
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Why can't we kill ourselves by holding our breath?
Is it possible to kill yourself by holding your breath?
This question is obviously copied from Quora, but I had heard it as a fact that we cannot kill ourselves by holding our breath and I'm looking ...
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Immediate cause of death due to dehydration
When we don't drink we get dehydrated and after some time we die. What is the cause of death on the lowest level?
I would assume the dielectric properties around/in the heart tissue get imbalanced ...
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What is the death mechanism of an electrocuted Mosquito?
While using the Electric bat, does the mosquito get killed by primary electrocution, or it secondarily by burning?
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Why do eyes change colour after death?
Why exactly do eyes turn black when we die? (Or even change colour at all).
The source of inspiration to this question is due to this video https://www.youtube.com/watch?v=6mNs_TcUyHc&t=627s (it's ...
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Why do living things go belly up as they die? [closed]
I have seen birds, lizards, frogs, fish, etc in various places on their back dead. May be insecticides cause them to flip over but I do not believe every upside down creature died by poison as stated ...
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What is the fundamental reason for death from too high or low internal temperature?
I have read something about why we die from too high or too low body temperature but have always found only general reasons. For example, that the liver fails. But why does the liver fail?
I would ...
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Do dead cells always contain no nucleus?
If I examine a dead cell, can I be sure that it has not a nucleus?
And what about the other organelles?
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How to surpass cell death?
Is it possible to surpass/decay cell death. For example to disable the process muscles cells death, by tweaking the transduction pathways:
If it's not possible in our age Medicine, what it would ...
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When is a person declared to be dead?
From what I can tell, it is not well defined, but at least in the US it has to do with cessation of cardiopulmonary functionality. Any reliable sources that give a definition of when a human being is ...
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Is it possible for a human to live forever if he/she didn't catch any diseases?
Aging is not a disease, but it's the gradual weakening of the body, as the body gets weaker it gets more prone to diseases. So one doesn't die from aging but from diseases. So if one didn't catch any ...
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Will neurons die if they are inactive for a long time?
We know that when muscles are not used they atrophy. Does something similar also happen in neurons if they do not receive any stimulus?
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What is the medical definition of death?
What is the medical definition of death? And how do medical examiners determine whether a person has really deceased, as opposed to for example a condition like brain death?
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Which extinction event killed the highest proportion of organisms?
The P-T extinction (a.k.a. the Great Dying) tends to be considered the worst - for example, Wikipedia states:
It is the Earth's most severe known extinction event, with up to 96% of all marine ...
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Decomposition of human body after death
What causes decomposition of human body after death? Here it says autolysis, while Here it says that bacteria decompose the body. If bacteria decompose the body, why don't they do while we are living?
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Do ants really dispose of their own dead, and how/why?
I just read this from Wikipedia's Swarm Behavior article:
Despite the lack of centralized decision making, ant colonies exhibit complex behaviour and have even been able to demonstrate the ability ...
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Alternative conditions for Liquifactive Necrosis
A person is beaten on the head hard enough to swell the whole front part of the head. The body is thrown into the river and recovered after about 36 hours. Is this condition enough for liquifactive ...
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What is operating temperature of the human brain?
I've heard several times that human brain can die in temperatures over 40 °C, or under 10 °C, as an engineer I'm curious.
In what temperature region can brain properly work?
And just an underlying ...
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Does mechanical shock kill animals?
I heard that loss of blood kills shot animals, a lot. But a few times, I heard that mechanical shock kills animals. For example in this video (starts to play at the right spot; relevant from 14:35 to ...
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At what point is a picked flower considered dead?
Let a flower be picked from the ground such that its stem is cut and the flower is separated from the root system (as in figure).
Questions:
1a. At what point is it considered dead?
Does the flower ...
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Aging and death of perennials
Perennial plants species generate a new plant annually from the same parent root stock. At the end of the year that new shoot withers and dies, to re-appear the next year. Hence, the above-ground ...
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Can rigor mortis change the anatomical position in which a person died?
I've been told as an undergrad in anthropology that the flexed position of the body in which some Neanderthal skeletons were found indicates that they were deliberately buried. Apart from the good ...
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How long do tiny spiders live? [closed]
I'm pretty sure there's a spider in my ear. I feel it move and hear the scratching (i blame my cat for playing with bugs in the bed). I've gone to the doctor, but all they do is flush my ear with ...
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how long after death can a body exhibit an immune response
I suppose this is part of a larger question - at what point do the body's coordinated systems (Endocrine, Autonomic nervous system etc) begin to fail? Within hours? Days? Minutes?
Of course this ...
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How does glutaraldehyde kill bacteria?
How does glutaraldehyde kill bacteria?
After disinfecting, does it leave the corpses of the bacteria to count?
Does it leave bio-film in tact?
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Single celled organism and immortality
My biology book says:
No individual is immortal,except single celled organisms..
I think that such conclusion aries from the necessity of binary division in many single celled organism to ...
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What causes drone bees to die?
... when not killed by other members of the hive.
Is it always a consequence of exile (denial of some resource, etc) or does some organ fail regardless of circumstances?
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Does an increased reproduction/mortality rate provide an evolutionary advantage?
If a species has a high mortality/birth rate, then it is able to adapt to changing environments more quickly than species that live for a long time.
Without a high mortality rate, food and other ...
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What would kill you first water or cola? [closed]
After discussing this with some colleagues, I devised the theory that you could drink more coca-cola in a single sitting than you could water, without killing you.
Defining the volume it would take ...
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Does reproduction cause aging ? Is aging just a strategy to increase reproductive success in all organisms? [closed]
Background for why I am asking this:
I read a book—modern biological theory and experiments on celibacy— which uses life history theory to imply that reproduction is the reason why organisms grow old....
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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 ...
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Why does fever above 102 herald a cancer patient's death?
I was recently intrigued by a longtime hospice nurse's observation that her cancer patients die a different death than her Alzheimer's, multiple sclerosis, heart failure and COPD patients.
She stated ...
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