Survivorship curve = so, first of all, it's a curve, as in a graph.
It describes "survivorship" - the rate of survival, in other words: out of 100 organisms that are born, how many survive. This rate is different among species, for example, most humans live out to most of their life span, and almost all can survive well beyond a reproductive age.
However, in frogs for example, many many individuals are born, but only few can survive to adulthood: most die very young, before reproductive age.
So if you hear about a new species: let's say dogs, and you want to know how long they would live, you would look at their sirvivorship curve (and in some breeds of dogs, those that are likely not to be in shelters, but in homes, the survivorship curve would be similar as in humans: almost all individuals born can live long.
Eukaryotic cells posses a nucleus the purpose of the nucleus is it stores DNA which is the genetic material for the cell DNA acts as an instruction manual for the other organelles in the cell. While prokaryotic cells do not have a nucleus they still have dna but it’s floating around freely
