Question

question 23

the phospholipids that make up the cell membrane are ___.

• partly polar and partly nonpolar
• nonpolar
• polar
• made of water

question 24

all of the following are examples of passive transport except ___.

• simple diffusion
• osmosis
• exocytosis
• facilitated diffusion

Explanation:

Analyze phospholipid structure

Using the Phospholipid Bilayer knowledge point

Phospholipids are amphipathic molecules containing hydrophilic (polar) phosphate heads and hydrophobic (nonpolar) fatty acid tails. Therefore, they are partly polar and partly nonpolar.

Define passive transport

Passive transport is the movement of substances across a cell membrane down their concentration gradient without the expenditure of cellular energy (ATP).

Evaluate transport examples

Simple diffusion, osmosis, and facilitated diffusion are all passive processes that do not require energy. Exocytosis is a form of active bulk transport that requires energy (ATP) to move materials out of the cell via vesicles.

Answer:

Question 23

• (A) partly polar and partly nonpolar (Correct answer)
• (B) nonpolar
• (C) polar
• (D) made of water

Question 24

• (A) simple diffusion
• (B) osmosis
• (C) exocytosis (Correct answer)
• (D) facilitated diffusion