Anton van leeuwenhoek is a scientist who saw cells soon after hooke did. he made use of a microscope containing improved lenses that could magnify objects almost 30ox. under these microscopes, leeuwenhoek found moving objects that he named "animalcules," which included protozoa and other unicellular organisms, like bacteria. he was also able to observe red blood cells and sperm cells. to which of the tenets of the cell theory did leeuwenhoek make the biggest contribution?

D)The cell is the basic unit of structure and organization in organisms.

Explanation:

Just took the test on USATest Prep

answer: c

explanation:

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.