Two ways of making a new one
Reproduction takes two forms — sexual and asexual.
Two germ cells from two organisms of the same species — a male gamete and a female gamete — join to form a zygote.
That zygote is the very first cell of the process that builds a new organism.
Without the participation of any other organism, a single organism can produce another one like itself.
Example — organisms propagating through vegetative parts.
The zygote again
In section 8.1 the zygote appeared as an example of cellular organization — the single cell a multicellular organism begins from. Here it appears as the result of reproduction. The same cell, seen from two directions.
What is the difference between the two?
In sexual reproduction the characteristics of two parents are mixed, so the offspring is identical to neither. In asexual reproduction there is only one parent, so the new organism is identical to it. Generalising that "offspring resemble their parents" is therefore wrong.