recently i got into a debate with this question on hinduism.se ,
as the link given above shows, are sperms considered as living or non-living
as far as my knowledge is concerned, sperms undergo locomotion, senescence, more over the best thing to say they are living is they contain genome, i.e. haploid sets of chromosomes
so in short are sperms living or non-living
The question of what is living is nothing but a matter of definition. We can only tell you what are the standard definitions of what is a living thing but no absolute truth exist behind these definitions. Therefore, I am afraid that all discussions here will bring anything new to your ethic or religion related discussion.
I want to argue that the @user137's answer is very misleading for two reasons. First, he based his discussion exclusively on the "reproduction ability" definition of life. Second because his definition of reproduction might be misleading as well.
Reproduction is not only cell division obviously. Following this same definition one would not consider a human to be a living things but only to be a collection of living (and non-living) things. It is important to understand that a spermatozoid is just one phase of a life-cycle. This phase yield to the next phase. That's it. It seems weird to say that a kid is not alive just because he cannot reproduce. It seems weird to say that a grandmother is not alive because it cannot reproduce. You can say however that a kid is a living thing that cannot reproduce and at another moment of its life cycle it will be able to reproduce (assuming it will survive to this age). One should not think of spermatozoids as something totally detached from the human phase as we know it. These things just form a cycle and it seems to me miseleading to say that a part of this cycle is not alive. Saying such thing would yield someone to think that two living things create non-living things that by fusion will become alive. That seems weird. But again, it is nothing but a matter of definition. I cannot say that user137 is wrong, I cannot only say that his definition seem neither useful, intuitive nor common among biologists.
You may want to have a look to life-cycle and to understand what are the haplontic and diplontic phases with a bunch of wikipedia readings.
Other concepts such as the ability to synthesize its own components, having a boundary between interior and exterior and ability to response to environmental stimulis are often used in order to define what is a living thing and what is not.
Damn.. this is getting into a huge debate.
There are different levels of life. What we mean by living when we say living is generally an Organism.
This is highly debatable. If you say viruses are nonliving because they need a host then almost every hetertroph is nonliving because they need the support of autotrophs.
An organ is living as long as it remains inside the body; similarly a cell in a multicellular organism can be considered alive only if it remains associated with the multicellular whole.
So is a single man alive?? Well he can eat, carry out metabolism, form a habitat but he cannot reproduce. Man as an organism is alive as he can sustain cell division and metabolism within himself but in that restricted zone human population is dying. He is living because he has the potential to reproduce. It is same as a lone enzyme- it can carry out its metabolism but will one day degrade unless it is re-formed.
Sperm on the other hand is just a vehicle- it doesn't have the potential to sustain itself; its sole aim is to deliver the potential to the egg so that life can be created.
To conclude- the question of what is "life" is purely philosophical. A more scientific question would be - "What is a stable, self-sustaining and dynamic biological system"
Sperm are unquestionably alive, according to all or most sensible definitions of life (They move around, they have goals, they eat things, they die). They are not, however, a human or animal life.
Vineet Menon has a shaky grasp of species definitions, and I'd like to correct some misunderstandings. Chromosome number is not that useful in distinguishing different species. There are a large number of genetic disorders that alter your chromosomal count without making you not a human being. (Klinefelter, Turner, Edward, Down, etc.) It's also worth noting that all mosses are haploid except during the sporophyte stage of their life cycle, when they're diploid. I doubt Vineet Menon intends to categorically declare mosses 'not alive'.
Your blood is alive, and your feces is also thriving with bacteria. Some yogurt is alive, most cheese is alive. All fermented beverages are alive, or were once. Bread dough is alive. The argument you linked to is debating whether or not they are alive enough to qualify as a macroscopic living thing for ethical purposes, which is an entirely different question. A chicken definitely qualifies, single-celled algae like spirulina, mushrooms, and yeast do not. Eggs, fertilized or not, seem to be somewhere in the middle. It is a continuous spectrum with people and cats and chickens and things at one end, and viruses and tuberculosis and dirt at the other. Eggs and sperm and mushrooms I would put somewhere in the middle.
So whether the answer to the question 'Are gametes alive?' is unquestionably yes; The answer to the question of whether or not that makes them 'a life' is up to you.
Sperm, in my opinion can't truly be considered "alive"...but they are living. Bear with me before you skip my answer.
A cell can be considered a "living" thing since It has RNA/DNA, it imbibes nutrition, it grows and is destroyed, we cannot say however that it is alive. It has a specific set of instructions coded into the RNA which it follows till its death (which is also protein,and hence RNA, mediated). Alive is a term reserved for organisms and not single haploid somatic cells. On the other hand...sperms have spiral mitochondria hence they contain RNA. In short..yes..they can be considered living
Your best chance of actually reaching an answer for yourself (*) to this is by parallel.
Do you consider independetly-living single-celled organisms alive? This includes bacteria, amoeba, bacteria, some parasites such as plasmodium (the malaria germ), and more.
Sperms are not quite independently-living single-celled organisms. They have many things in common with the ones mentioned above: they move, metabolise, communicate and sense, and most importantly they can cease to do all those things, i.e. they do what we commonly call, "die".
The main difference is, they don't reproduce themselves, they are the reproduction vessel for a larger organism.
There is absolutely no objective way to decide whether that difference is sufficient to decide that all those single-celled creatures are alive and sperms aren't, it's a question of definition. You might even decide that you don't consider bacteria or anything that exists commonly as single cells "alive", and thus this whole approach is pointless. In any case, it's not a biological question and thus should be discussed somewhere else.
(*) For yourself because there is no false or correct answer as long as nobody can get more than two people to agree on a definition of life.
One requirement most biologists have to consider something living is the ability to reproduce. This is why viruses are generally not considered alive. They contain proteins and DNA or RNA, but require infecting a host cell and hijacking its replication machinery to reproduce itself.
Fully differentiated sperm cells cannot divide and therefore can't reproduce. Their only role is delivering DNA cargo to an oocyte and creating an embryo. An individual sperm cell is just as alive as an individual neuron or muscle cell. These require nutrients and energy, carry out metabolism, perform functions, contain DNA, but a plate of neurons won't grow into a human.
