Heartwood and Sapwood

Q.

Annual rings are the number of:

1. Internodes in a stem.

2. Rings of vascular bundles in a monocot stem.

3. Bark layers in a woody stem.

4. Layers of Xylem in a stem.

Q. Heartwood differs from sapwood in

1. Presence of rays and fibres
2. Absence of vessels and parenchyma
3. Having dead and non-conducting elements
4. Being susceptible to pests and pathogens

Q. Tyloses can be found in

1. cortical cells
2. endodermis
3. secondary xylem
4. secondary phloem

Q.

What is a branch gap?

Q.

Duramen is

1. Sapwood

2. Heartwood

3. Bark

4. Periderm

Q. Which of the following are involved in the conversion of sapwood into heartwood?

1. By degeneration of protoplast of living cells
2. Tyloses formation
3. By deposition of resins, oils, gums, etc
4. All of the above

Q.

Heart wood differs from sap wood in

1. presence of rays and fibres

2. absence of vessels and parenchyma

3. having dead and non-conducting elements

4. being susceptible to pests and pathogens

Q. Assertion :Most epiphytes face a situation of drought. Reason: The epiphytic roots are hygroscopic because of special tissues, the velamen.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

Heartwood helps in

1. Ascent of sap

2. Mechanical support

3. Ascent of sap and mechanical support

4. Translocation of food

Q. The feature which is common to both heartwood and sapwood is

1. both are the regions of secondary xylem
2. both are involved in the conduction of water
3. both are located in the central layers of the stem
4. both comprise dead elements with accumulation of aromatic compounds

Q. Read the following statements.
A. Heartwood is durable, dark and central in position.
B. Tyloses are balloon like outgrowths of xylem parenchyma into the lumen of vessels.
C. Late wood is formed during spring season.

1. All are correct
2. Only A is correct
3. Only B is incorrect
4. Only C is incorrect

Q. The wood that comprises dead elements with highly lignified walls is called .

1. sapwood
2. early wood
3. late wood
4. heartwood