What was gan de's contribution to astronomy

Which of the following describes a difference when gram-positive bacteria are compared to gram-negative bacteria?

Long-period comets come from the oort cloud particles in earth’s atmosphere material from the asteroid belt the kuiper belt

Mitosis creates two identical daughter cells from one parent cell creates four nonidentical daughter cells from one parent cell is the most common type of reproduction for bacteria is the process by which male and female reproductive cells are created