What can lead to new characteristic in an organism?

a. spontaneous generation
b. mutations
c. enzymes
d. mitosis

What advantages does a pedigree have over a written passage?

Temperatures in ponds and lakes vary by season. select the best answer from the choices provided t f

Abird flies by moving its wings up and down. which two systems are most directly responsible for the movement of a bird's wings? a. skeletal and muscular systems b. respiratory and muscular systems c. skeletal and digestive systems d. respiratory and digestive systems