How many of the following statements are true for heartwood?
I. It provides mechanical support to the stem
II. It does not conduct water
III. It is hard, durable, and resistant to the attacks of microbes
IV. It is the innermost layer of the wood
V. It comprises dead elements with highly lignified walls
VI. More the heartwood is present, the better is the quality of the wood
1. Four
2. Five
3. Six
4. Three
In dicot roots, secondary phloem is formed towards the _________ and secondary xylem is formed towards the __________ by the activity of vascular cambium.
1.periphery, centre
2.centre, periphery
3.innerside, outerside
4.Both 2 and 3
Axillary bud is the left part of ________ meristem and may form _____or a _______ further
1.shoot, branch, flower
2.shoot, leaf, flower
3. root, branch, flower
4. root,leaf, flower
In the life cycle of a plant, the secondary tissues are made by
1. Intercalary meristem and vascular cambium
2. Apical meristem and cork cambium
3. Cork-cambium and vascular cambium
4. Primary meristems and interfascicular cambium
The springwood present in an annual ring
1. Is dark colored
2. Has high density than autumn wood
3. Has abundant fibers
4. Has low density than autumn wood
Dicot roots do not have cambium in vascular bundles, but secondary growth cambium is served from
1. Pericycle cells only
2. Pericycle and conjunctive tissue
3. Conjunctive tissue only
4. Pericycle and cortex
Which of the following is secondary in origin?
1. Phellogen
2. Interfascicular cambium
3. Wound meristem
4. More than one option is correct
Identify the incorrect match with respect to wood characters given in A, B, C column
A B C
1. | Early Wood | Large no. of xylary elements |
Springwood | wide cavities |
2. | Latewood | Few xylary elements |
Autumn wood | Narrow cavities |
3. | Heartwood | Dark brown in Colour |
Dead elements | Filled with resins and gums |
4. | Sapwood | Light in color | Living elements | Conducts minerals only. |
Select the incorrect statement with respect to late wood
1. It forms a narrow strip in annual rings
2. Has smaller and narrower vessels
3. Darker in colour
4. Fibres are less
Secondary meristems are found in
1. All angiosperms
2. Gymnosperms and all monocots
3.Dictos and gymnosperms
4. All spermatophytes