What are the major organs of the respiratory system and why are they each individually important?

Jason adds the antibiotic penicillin to a bacterial culture. the bacteria develop genetic modifications in their genome, which gives them resistance to the antibiotic penicillin. what caused this genetic modification?

Immature bone cells, or osteoblasts, manufacture a protein called osteoid as well as several hormones. because of this, we would expect osteoblasts to contain numerous a) nuclei. b) ribosomes. c) lysosomes. d) golgi bodies.

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm