Phloem Transport

Q. In phloem transport, the source-sink relationship is variable. Identify the statements in support of this.

1. Food is primarily transported as sources through phloem

2. Sugar stored in roots may be mobilized to buds in early spring

3. The direction of movement in phloem can be upwards on down wards i.e., bidirectional

4. Both b & c

Q. Major components of phloem sap are _______.

1. Minerals and sugars

2. Sucrose and amino acids

3. Sugars and hormones

4. Water and sucrose

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. if both A and R are true and R is the correct explanation of A

2. if A is true but R is false

3. if both A and R are true but R is not the correct explanation of A

4. if both A and R are false.

Q.

The transport in xylem in usually unidirectional, whereas in phloem it is bidirectional.

1. True

2. False

Q. In phloem transport, the source-sink relationship is variable. Identify the statements in support of this.

1. Both b & c

2. Sugar stored in roots may be mobilized to buds in early spring

3. The direction of movement in phloem can be upwards on down wards i.e., bidirectional

4. Food is primarily transported as sources through phloem

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. Active transport and passive transport

2. Passive transport and active transport

3. Active transport

4. Passive transport

Q.

Phloem is a vessel in plants which carries

1. food and minerals to leaves from roots

2. prepared food to other parts from roots

3. food and minerals to roots from leaves

4. prepared food to other parts from leaves

Q.

Which of the following is not a purpose of transpiration?

1. Supplies water for photosynthesis.

2. Helps in translocation of sugars from source to sink.

3. Cools leaf surface.

4. Transports minerals from the soil to all parts of the plant.

Q. Which of the following isotopes would be useful in finding the path of translocation of food?

1. 
2. 
3. 
4. 

Q.

The transport in xylem in usually unidirectional, whereas in phloem it is __.