Which of the following best describes the process of meiosis?
a) it is the first stage of mitosis.
b) it occurs in all tissues that require growth or replacement.
c) it happens in all cells except in the brain and nervous system.
d) it is carried out in cells that are involved in sexual reproduction.

The observations of hooke and van leeuwenhoek documenting the existence of microscopic cells formed the basis of what important theory? a. the cell theory stating that all living things are composed of cellsb. the theory of spontaneous generation, which held that life forms could arise spontaneouslyc. the theory of chemotherapy, or use of antimicrobials to destroy pathogenic organismsd. the germ theory of disease and causative agents

The theories on the expansion of galaxies maybe re-examined to strengthen science should not be tested to strengthen science will weaken scientific knowledge if they change will become laws if they don't change

Vinegar has a ph of 3, and household ammonia has a ph of 11. is the concentration of h+ greatest in the vinegar or ammonia?