Prepare for NEET Biology Transport in Plants with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert guidance to understand xylem, phloem, and movement of water.
The apoplast pathway in plants is interrupted by the Casparian strip. Which of the following statements about its impact on water movement is most accurate?
It forces water and dissolved minerals to enter the symplast before reaching the stele.
It facilitates the rapid movement of water through the cortex via plasmodesmata.
It prevents the passage of water into the root hair cells.
It increases the rate of transpiration by reducing the resistance to water flow.
Guttation in plants is primarily caused by:
Root pressure exceeding transpiration pull
High transpiration rates during the day
Opening of stomata at night
Active transport of water into xylem vessels
Facilitated diffusion differs from simple diffusion in that:
Facilitated diffusion requires membrane proteins, while simple diffusion does not.
Facilitated diffusion moves substances against their concentration gradient, while simple diffusion moves them down their concentration gradient.
Facilitated diffusion requires energy expenditure, while simple diffusion does not.
Facilitated diffusion occurs only in plant cells, while simple diffusion occurs in all cells.
The movement of oxygen from alveoli to pulmonary capillaries is best described as:
Active transport requiring ATP
Facilitated diffusion via carrier proteins
Simple diffusion driven by a partial pressure gradient
Osmosis across a semipermeable membrane
Which of the following is NOT a characteristic of facilitated diffusion?
It requires specific membrane proteins.
It does not require ATP.
It is a passive process.
It moves substances against their concentration gradient.
In facilitated diffusion, saturation occurs when:
The concentration gradient disappears.
All carrier proteins are occupied by the transported substance.
The cell runs out of ATP.
The temperature decreases significantly.
Facilitated diffusion differs from simple diffusion in that it:
Requires ATP
Moves substances against their concentration gradient
Requires membrane proteins
Occurs only in plant cells
Facilitated diffusion is different from simple diffusion because it:
Moves molecules against the concentration gradient
Uses carrier proteins
Requires ATP
Occurs only in plant cells
Which type of molecule is LEAST likely to cross a cell membrane by simple diffusion?
Small, nonpolar molecule
Small, polar molecule
Large, polar molecule
Small, uncharged molecule
What happens to the rate of facilitated diffusion as the concentration of the transported molecule increases?
It increases linearly
It decreases
It reaches a maximum rate (saturation)
It remains constant
