Like, probably, but I think this is an interesting and non-trivial question. I’m not actually 100% sure about the answer; I’m probably 97% sure of the answer. But the correct answer doesn’t actually affect the value of thinking about this question.
Even if you know a lot of biology, there is an explanation that a biologist could give about how apples are actually not made of cells which would, I claim, be pretty convincing. How much detail would they have to give before you believed them? Even if it turns out to be false, it’s good practice to know what it feels like on the inside to have your mind changed about something. Can you imagine what the biologist could say that would change your mind? Think about this for a second before reading on.
You learn pretty early on in biology class that all life is made of cells. (We’re not getting into the issue of viruses, here.) It’s pretty much what life is; cells are the level at which the replication occurs, so life begetting life is cells begetting cells.
But cells are extremely complicated and messy and made of lots of sub-parts. And they can produce bulk materials that are useful to the organism: materials which are not themselves made of cells. Tissues need to be made of cells in order to perform complex functionality that is locally responsive to the molecular conditions around it. Cells have the machinery to control what goes in and out, and control which genes get expressed when.
But not all parts of organisms need this.
Your hair and fingernails and outer skin layers are kind of cells but kind of not. They’re dead cells, flattened together and drained of most of their contents.
The enamel in your teeth is not made of cells. It just needs to sit there being a rock. This does come at the cost of self-repair, hence dentistry being a major category of medical care.
Bones are in large part made of minerals, which is to say, tiny rocks, which I would claim are not cells. But these minerals seem to be fractally mixed-in with the myriad organic operations of the bones, almost as though bones are perfectly calibrated to queer the made-of-cell/not-made-of-cells binary.
Your bladder is full of, let’s say, non-cellular fluid.
And some cells are very large. Eggs are often cited as large cells (though it’s very unclear to me whether this is true), with the ostrich egg being the largest. Could apples be giant, single plant cells? How sure are you?
So, what’s up with apples? Is there some minimal cellular machinery around the edges that packs in the sugars, pumping nutrients in through the stem, making sure the skin grows in proportion, with the bulk of the apple mass being undifferentiated acellular deliciousness? Or is it cell walls all the way through, crunching crisp copies of every chromosome?
If you were the first discoverer of cells, you would need to spend a while going around and checking different types of tissues before you could justify the generalization “all life is made of cells”. And I think fruit is a category where you would be less justified in generalizing to.
So how could you tell? Are there ways other than looking it up, or using a microscope?
My whack at discerning without looking it up:
Fruits perform bulk chemical reactions in response to trace hormones (or at least hormone, ethylene, but I recall it’s more than that), which makes me strongly suspect they are doing metabolism, and hence cells, or at least suffused with cells bone-style.
I can’t get spoiler tag to work so here it is
The seeds at least need to contain cells, because new plants with cells grow out of them. It’s not a single cell because it’s solid on the inside—I don’t know any living cell that is, and it would be very difficult for substance transport. It also shows cell damage: a cut apple browns on the air, and the sharper the knife the less it does it. I don’t think a case like bones can even be excluded without a microscope.
Another interesting one (and perhaps a bit squicky to some): if there are cells in an apple, are they typically alive when you eat the apple? How about cells in meat? How do you know?
Without looking it up:
I assume so, up to a certain point. As long as the apple is able to germinate successfully, then it’s cells are probably still alive.
As it decays/decomposes, cells walls probably deteriorate. Eventually, it loses the ability to germinate?
Idk, I haven’t taken a biology class since 7th grade. ¯\_(ツ)_/¯
I feel pretty confident it’s made of cells.
(just answering off the top of my head without looking it up)
Of the non-cell bio-things you mentioned, there’s all a clear reason why they couldn’t be cellular: structural integrity (or extreme lack thereof). That’s not the case with apples (though plausibly the skin works similar to human skin).
Apples ripen in response to ethylene. It’s hard to imagine how that could trigger a complicated ‘ripening’ response throughout the entire apple without cellular machinery. This also makes me believe that the cells throughout must be alive still (at least pre-ripening). When apples first start to go bad, it doesn’t seem like it’s because of mold or bacteria, it just gets mushy in the sort of way I’d expect if the cells were simply dying.
The crispness is most easily explained (to my knowledge) by the stiffer plant cell-walls throughout. It’s not just applesauce inside, there’s something giving it a uniform texture.
And it can’t just be one cell, since that wouldn’t have internal structural integrity to the degree that it does, and also since the seeds, flesh, and skin are clearly different tissues.