3.5.1 Simple and Facilitated Diffusion

Question 1

diffusion

Answer 1

• the tendency for particles to move from an area of high concentration to an area of low concentration. The rate of diffusion depends on four main factors:
  1. The concentration gradient—the relative density of a chemical substance
  2. The temperature—molecules move faster at higher temperatures
  3. The charge—the net positive or negative charge on a molecule
  4. The diameter of the molecule—the width of a molecule

Question 2

facilitated diffusion

Answer 2

• applies to the movement of molecules across biological membranes and down a concentration gradient with the aid of special transport proteins located in the cell membrane

Question 3

Which of the following are not molecules that can facilitate passive diffusion?

Answer 3

• ATP regulated enzymes

Question 4

After placing Paramecium into a salt solution, you would expect that

Answer 4

• the cell will expend energy to move sodium out of the cell

Question 5

Which of the following is not a determinant of the speed of diffusion?

Answer 5

• Shape

Question 6

Which of the following statements concerning diffusion is not true?

Answer 6

• Diffusion is an energy-dependent process.

Question 7

Which of the following answers includes all of the other terms on the list?

Answer 7

• passive transport