3.5.1b The Movement of Substances across the Plasma Membrane (Objective Questions)

What is osmosis?

What are the main components that make up the plasma membrane of an animal cell?

Which of the following is true about facilitated diffusion?
I.     Movement of molecules across the plasma membrane with the help of transport proteins
II.   Movement of water molecules down a water potential gradient across a semi-permeable membrane
III. Movement of substances from a region of higher concentration to a region of lower concentration
IV.  Movement of substances across the plasma membrane without expending energy

The diagram shows the structure of a plasma membrane.

What are P and Q?

Which of the following is true about active transport?
I.      Movement of substances across the plasma membrane against the concentration gradient
II.    Movement of substances from a region of higher concentration to a region of lower concentration
III.  Movement of substances across the plasma membrane with the release of energy from ATP
IV.   Movement of substances across the plasma membrane with the help of carrier proteins