1 Prepared by Pradeep Jayathilaka 071 8899027

Viharamahadevi Balika Vidyalaya

4th

Unit – Plant form and Function

Biology – Structured essay and essay - 03

NB ( This questioner is prepared for English medium Students.

Before answering for the questions go through your Resource book.

Then answer for the all questions.

At the end of the answering compare your answers with the Resource book and

if there is mistake you should correct using Resource book.

If you reach any difficulty relate with subject matters contact your Biology

teacher.

26. What is called secondary growth of a plant?

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27. Which types of plants undergo secondary growth?

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28. What is the role of vascular cambium for secondary growth of a plant?

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29. Why cork cambium is important to plants?

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30. What are the regions of a plant which undergo secondary growth?

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31. Briefly explain the nature of vascular cambium of a typical woody stem.

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32. State the location of vascular cambium of a typical woody root.

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33.

i. What are the two types of initials of vascular cambium? State the orientation of each.

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2 Prepared by Pradeep Jayathilaka 071 8899027

ii. What are the products of above mentioned types of two initials

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34.

i. What is the type of cell in a woody plant that connects secondary xylem and

secondary phloem and store carbohydrates? …………………………………………………………………………………………

ii. State other function of above mentioned type of cell?

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35. What is the fate of epidermis when plant undergoes secondary growth?

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36. What is the product of cork cambium?

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37. What is called periderm?

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38. Mature cork cells are considered as dead cell. Explain why?

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39. What is called lenticels?

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40. What happens to existing cambium when stem of a plant further undergoes secondary

growth?

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41. What is called bark? What are the components of bark?

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42. Write an essay on Secondary growth of stem.

See the Appendix 01

3 Prepared by Pradeep Jayathilaka 071 8899027

Appendix 01

4 Prepared by Pradeep Jayathilaka 071 8899027

5 Prepared by Pradeep Jayathilaka 071 8899027