Does a cell have an identity?

[samsara15]

Can you tell one from the other, or are they all the same, within a given type? One liver cell, as an example, in the human body. At what level or organization does an identity appear? The organism? Does one single celled creature have the same DNA as another, of the same species?

 

[citizenzen]

At what level or organization does an identity appear?

When it becomes self-conscious... something my liver (or a fetus) has yet to achieve.

 

[palerider]

Can you tell one from the other, or are they all the same, within a given type? One liver cell, as an example, in the human body. At what level or organization does an identity appear? The organism? Does one single celled creature have the same DNA as another, of the same species?

It is not the number of cells,or the organization, per se', but rather the type of cell it is that would give it an identity. A liver cell for example can reproduce only clones of itself ad infinitum. It will never be, or produce more than a liver cell. This is true of most tissue cells in the body.

Stem cells are different but even most of them couldn't lay claim to an identity. Multipotent cells, for example, are stem cells but are very limited in the sorts of cells they can produce. Your bone marrow produces multipotent stem cells but they are only capable of differentiating into blood and bone marrow cells. Hardly worthy of an identity.

Pluripotent cells are capable of becoming any differentiated cell in the body. A nifty trick but still not warranting an identity as they simply become one of the multitude.

Totipotent cells, however, if left to their cycle are individuals worthy of an identity as their cycle is to grow and develop into an individual of the species. A zygote is a totipotent cell but it is also a human being and all human beings have an identity.

 

[palerider]

When it becomes self-conscious... something my liver (or a fetus) has yet to achieve.

Self consciousness doesn't happen for quite some time after birth and in some cases of mental retardation, it never happens. Are you saying that newborns to roughly 12 or 18 months and some of the mentally retarded are not worthy of an identity? You really should practice thinking through your arguments at least as far as their first order consequences. Then you wouldn't have people like me pointing out the flawed nature of your thinking.

I have to wonder if you have as little working knowledge of developmental biology as you admit to having in climate science? If that is the case, upon what basis do you hod your position? Is it faith as is the case with climate science?

 

[dahermit]

A zygote is a totipotent cell but it is also a human being and all human beings have an identity.

Just for my benifit, can you point out which of the definitions below apply to a zygote/totipotent cell?

Main Entry: identity I-!den-tu-tE
Pronunciation: \ ī-ˈden-tə-tē, ə-, -ˈde-nə- \
Function: noun
Inflected Form(s): plural iden·ti·ties,
Etymology: Middle French identité, from Late Latin identitat-, identitas, probably from Latin identidem repeatedly, contraction of idem et idem, literally, same and same
Date: 1570
Results

1 a sameness of essential or generic character in different instances b. sameness in all that constitutes the objective reality of a thing : oneness

2 the distinguishing character or personality of an individual : individuality
b. the relation established by psychological identification

3. the condition of being the same with something described or asserted - establish the ∼ of stolen goods

4. an equation that is satisfied for all values of the symbols

5. identity element

Merriam-Webster Online Dictionary copyright © 2010 by Merriam-Webster, incorporated