Question

The value of root pressure is about __________ to __________ bars which is enough to pump water to a height of 10 to 20 meters in plants.

• A. \(+1\) to \(+2\)
• B. \(+10\) to \(+20\)
• C. \(-1\) to \(-2\)
• D. \(-10\) to \(-20\)

Hint:

Root pressure is a small positive pressure in the xylem.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept
Root pressure is a positive hydrostatic pressure that builds in the xylem when root cells actively take in ions and water follows.

Step 2: Value
It is only about +1 to +2 bars.

Step 3: Check with height
One bar supports a water column of about 10 m, so 1 to 2 bars can raise water about 10 to 20 m.

Final Answer:
Root pressure is about +1 to +2 bars. \[ \boxed{\text{(A) }+1\text{ to }+2} \]