Question

in a hypertonic solution, water will move across the cell membrane.
equally in both directions.
out of the cell.
only through protein channels.
into the cell.
oxygen moves from a high concentration in the lungs to a low concentration in the blood across the cell membranes of lung cells. this is an example of:
simple diffusion (a type of passive transport).
active transport.
facilitated diffusion.
osmosis.
when a cell is placed in an isotonic solution:
active transport will occur.
there will be no net movement of water across the cell membrane.
the cell will swell and potentially burst.
the cell will shrink.
which of the following transport mechanisms relies solely on the kinetic energy of molecules and the concentration gradient to move substances across the cell membrane?
active transport.
enzymes.
endocytosis.
simple diffusion.

Explanation:

Step1: Understand hypertonic solution

In a hypertonic solution, there is a higher solute - concentration outside the cell compared to inside. Water moves from an area of lower solute concentration (inside the cell) to an area of higher solute concentration (outside the cell) to equalize the solute - water ratio. So water moves out of the cell.

Step2: Analyze oxygen movement

Oxygen moves from an area of high concentration (in the lungs) to an area of low concentration (in the blood) across the cell membranes of lung cells. This is a passive process that does not require energy and is an example of simple diffusion.

Step3: Consider isotonic solution

In an isotonic solution, the solute concentration inside and outside the cell is the same. So there is no net movement of water across the cell membrane as there is no concentration gradient to drive the osmosis.

Step4: Identify transport mechanism

Simple diffusion relies solely on the kinetic energy of molecules and the concentration gradient to move substances across the cell membrane. Active transport requires energy (ATP), endocytosis is the process of taking in substances by forming vesicles, and enzymes are biological catalysts not directly related to this type of transport.

Answer:

1. Out of the cell.
2. Simple diffusion (a type of passive transport).
3. There will be no net movement of water across the cell membrane.
4. Simple diffusion.