Assertion: Pits connecting individual tracheids and vessels members to other tracheids or vessels is an adaptation against cavitation.
Reason: Air bubbles can easily pass through the pits clearing the tracheids and vessels of cavitation.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
3. If the assertion is true but the reason is false
4. If both the assertion and reason are false

Assertion: Turgor in guard cells results from the active uptake of ${\mathrm{K}}^{+}$
Reason: The energy required to move the ions across the guard cell membranes comes from ATP-driven ${\mathrm{H}}^{+}$ pump.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false

Assertion: Increased turgor in guard cells opens stomata.
Reason: Rings of cellulose microfibrils prevent the width of the guard cells from swelling, and only allow the extra turgor pressure to elongate the guard cells.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R): 
 

In the light of the above statements choose the correct answer from the options given below:
 

Assertion: Blue light as a signal induces stomatal closure.
Reason: Blue light inhibits proton $\left[{\mathrm{H}}^{+}\right]$ transport.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Phloem sap moves form sugar source to sugar sink.
Reason: A storage organ, such as a tuber or bulb, may be a source or a sink, depending on the season.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: The concentration of free sugar in the sink is always lower than in the sieve tube.
Reason: The unloaded sugar is consumed during growth or metabolism or converted to insoluble polymers such as starch.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Removing sinks is a useful horticulture practice such as in production of larger sized apples.
Reason: If sinks are more than the source can support, plants may undergo self-thinning.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Diffusion:
I. does not require any energy expenditure
II. is dependent on a living system
III. is a fast process
IV. is the only means for gaseous movements in plants
1. Only I and IV are correct
2. Only I, II and IV are correct
3. Only I, III and IV are correct
4. Only II and III are correct

Substances that have a hydrophilic moiety:
1. have to be transported across the plasma membrane by active transport
2. can diffuse across the plasma membrane at a slower rate, if larger in size
3. do not need a concentration gradient to diffuse across the plasma membrane
4. need to be facilitated even along the concentration gradient