Question

Match the following lists and select the correct option:  

List-I 
I. Early wood 
II. Late wood 
III. Duramen 
IV. Alburnum 

List-II 
A. Light in colour 
B. Dead elements, lignified walls 
C. Less xylem vessels 
D. More xylem vessels 

List-III 
P. Have wider lumen 
Q. Have narrow lumen 
R. Mechanical support 
S. Conduction

• A. I-B-S, II-C-R, III-D-Q, IV-A-P
• B. I-B-R, II-A-S, III-C-Q, IV-D-P
• C. I-D-P, II-C-Q, III-A-S, IV-B-R
• D. I-D-P, II-C-Q, III-B-R, IV-A-S

Hint:

Early wood = large vessels and wider lumen. Heartwood = dead and supportive. Sapwood = living and conductive.

Answer 1

The Correct Option is D

Concept: Secondary growth produces annual rings consisting of early wood and late wood. Mature wood is differentiated into heartwood (duramen) and sapwood (alburnum).

Step 1: Early wood. Early wood develops during favorable seasons. It possesses:
• More xylem vessels
• Wider lumen Thus: \[ I \rightarrow D-P \]

Step 2: Late wood. Late wood forms during less favorable conditions. It contains:
• Fewer vessels
• Narrow lumen Thus: \[ II \rightarrow C-Q \]

Step 3: Duramen (Heartwood). Heartwood consists of dead cells with heavily lignified walls. Its major role is mechanical support. Thus: \[ III \rightarrow B-R \]

Step 4: Alburnum (Sapwood). Sapwood is lighter in colour and actively conducts water. Thus: \[ IV \rightarrow A-S \]

Step 5: Final matching. \[ I-D-P,\; II-C-Q,\; III-B-R,\; IV-A-S \] Hence option (D) is correct.