Author Question: When a substance crosses a cell membrane without the assistance of a transport protein or ... (Read 63 times)

anjilletteb

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When a substance crosses a cell membrane without the assistance of a transport protein or expenditure of energy, this process is categorized as a type of passive transport called _______________.
 Fill in the blank(s) with correct word

Question 2

Excessive intake of fluoride causes:
 a. gastrointestinal upset.
  b. general malaise.
  c. pitting and mottling of teeth.
  d. bleeding gums.



ms_sulzle

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Answer to Question 1

simple diffusion

Answer to Question 2

c



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