Phloem Transport

Q. Which of the following is/are present in the phloem sap?

1. Sucrose
2. Hormones
3. Amino acids
4. All the above

Q.

A girdled tree may survive for some time but it will surely die because of

1. Water will not move upwards

2. Water will not move downwards

3. Sugars and other organic materials will not move downwards

4. Sugars and other organic materials will not move upwards.

Q.

Loading of sucrose into sieve tube cells is by (i)_______ and the unloading of sucrose from the sieve tube cells is by (ii)________.

1. (i) active transport (ii) passive transport

2. (i) passive transport (ii) active transport

3. (i) active transport and (ii) active transport

4. (i) passive transport and (ii) passive transport

Q. Assertion: Phloem transports solutes towards the sink.
Reason: Turgor pressure helps in the movement of sap through the phloem.

1. A is correct and R is the correct explanation of A
2. Both A and R are correct. But R is not the correct explanation of A
3. Only A is correct
4. Both A and R are incorrect

Q. Who among the following conducted an experiment to show that phloem is the tissue responsible for translocation of food?

1. Dixon and Jolly
2. Marcello Malpighi
3. Ernst Munch
4. Jan Ingenhousz

Q. Nina's backyard is adorned with a canopy of trees which she loves to watch. A few weeks back, her father had removed a ring of bark from one of the trees for his carpentry work. Nina noticed that the portion of the bark above the ring on the stem is now swollen. What could be the possible reason for this?

1. Shrivelling of the tissues below the ring of bark
2. Absence of downward movement of food
3. Phloem layer is removed from the tree trunk
4. All the above

Q. Major components of phloem sap are _______.

1. Water and sucrose
2. Sugars and hormones
3. Sucrose and amino acids
4. Minerals and sugars

Q. Statement 1: The translocation of food is always from source to sink.
Statement 2: Translocation in phloem is bidirectional.

1. Statement 1 and Statement 2 are correct
2. Statement 1 and Statement 2 are wrong
3. Statement 1 is correct and Statement 2 is wrong
4. Statement 1 is wrong and Statement 2 is correct

Q. Consider the following statements regarding the fate of a ring girdled plant and choose the most appropriate answer.

1. Both the shoot and root of a ring girdled plant die together.
2. The shoot of the plant dies first followed by the root.
3. The root of the plant dies first followed by the shoot.
4. Neither the root nor the shoot will die.

Q.

Assertion: The phloem sap moves towards the sink.

Reason: The process of loading at the source produces a hypotonic condition in the phloem.

1. Both A and R are true and R is the correct explanation of A

2. Both A and R are true but R is not the explanation of A

3. A is true but R is false

4. Both A and R are false.