Which of the following statements are true regarding passive transport? Choose 2 answers:
Simple diffusion, a type of passive transport, requires the use of membrane proteins.
Carbon dioxide can pass through a cell membrane via passive transport.
Oxygen cannot enter a cell through passive transport.
Charged ions cannot pass through a cell membrane via passive transport.

Imagine you are introducing the lac operan and the trp operon to students who have never learned about it before. complete the table to compare the similarities and differences between the two operons

Juan and carol were studying invertebrates in biology. they knew that segmented or earth worms preferred a dark, moist habitat. during this lab, they would be investigating the responses of organisms called planaria or dugesia tigrina. these were simple flatworms that still had a one-way digestive system and a very simple nervous system. juan and carol placed the planaria in a petri dish containing cool, distilled water that was partially covered with black paper. they shined a light on the dish. next, they removed the paper and placed a small amount of chicken liver at one end of the dish. they added a few large salt crystals to the water. finally, they added drops of hot water to the cool water in the petri dish. their results can be seen in the data table. according to their experiment, all but one conclusion is valid.

During convection, less dense fluid rises and denser fluid sinks.