Five chapters
cell engineering
embryo engineering
Safety and ethical issues of biotechnology
ecological engineering
The number of chapters in Biology 3 varies by edition and region. Taking the Human Education Edition as an example, the chapters of Biology Elective 3 include genetic engineering, cell engineering, embryo engineering, safety and ethical issues of biotechnology, ecological engineering, etc.
I hope the above information is helpful to you, and the specific chapters are subject to the teacher's teaching book.