Question

According to the passage, why does water travel through plants in unbroken columns?

• A. Root pressure moves the water very rapidly.
• B. The attraction between water molecules is strong.
• C. The living cell of plants pushes the water molecules together.
• D. Atmospheric pressure supports the columns.

Hint:

Cohesion means attraction between similar molecules. In plants, cohesion between water molecules helps maintain continuous water columns.

Answer 1

The Correct Option is B

Concept:
This question is based on passage comprehension and also relates to the biological concept of cohesion. Water molecules attract each other due to hydrogen bonding. This attraction between similar molecules is called: \[ \text{cohesion} \] Cohesion helps water move through plants as continuous columns.

Step 1: Understand the phrase “unbroken columns”.
Water moves upward in plants through xylem. For this upward movement, the water column must remain continuous. If water molecules did not stick together, the column would break easily.

Step 2: Identify the main reason.
The passage states that water travels in unbroken columns because water molecules strongly attract one another. This is due to cohesion.

Step 3: Check the options.
Option (A) Root pressure helps water movement but is not the main reason for unbroken columns.
Option (B) Strong attraction between water molecules is correct.
Option (C) Living cells do not push water molecules together in this context.
Option (D) Atmospheric pressure is not the passage-based reason here. Hence, the correct answer is: \[ \boxed{(B)\ \text{The attraction between water molecules is strong.}} \]