Which of the following produce intrinsic factor?
a. parietal cells
b. zymogenic cells
c. mucous neck cells
d. enteroendocrine cells

Which statement correctly describes a way that mutations increase the likelihood that a species will survive in a changing environment

Where is the nictitating membrane found? a. between the eyelid and the eyeball b. between the retina and the optic nerve c. between the outer and middle ear d. in the organ of corti in the middle ear

What is an example of a scientific question that galileo could not have answered with out this new tool?