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Class 9 Biology: Tissues NCERT Chapter 2 | Study Notes Page 3 | Complex Permanent Tissues Unlike simple permanent tissues which are made of one type of cell, Complex Tissues are made of more than one type of cells. All these cells coordinate to perform a common function. The most common examples are Xylem and Phloem. They are both conducting tissues and constitute a vascular bundle. 1. Xylem Xylem consists of tracheids, vessels, xylem parenchyma, and xylem fibres. + Function: Conduction of water and minerals vertically from roots to other parts. + Cell Walls: Most cells are dead and have thick lignified walls. 2. Phloem Phloem is made up of five types of cells: sieve cells, sieve tubes, companion cells, phloem fibres, and phloem parenchyma. + Function: Transports food from leaves to other parts of the plant. + Note: Unlike xylem, materials can move in both directions in phloem. NCERT IN-TEXT QUESTION Q1. Name the types of simple tissues. The three main types of simple permanent tissues are: 1. Parenchyma 2. Collenchyma 3. Sclerenchyma NCERT IN-TEXT QUESTION Q2. Where is apical meristem found? Apical meristem is found at the growing tips of stems and roots. Its primary function is to increase the length of the stem and the root. NCERT IN-TEXT QUESTION Q3. Which tissue makes up the husk of coconut? The husk of a coconut is made up of Sclerenchymatous tissue. These cells are dead, long, and narrow with thickened walls due to lignin. NCERT IN-TEXT QUESTION Q4. What are the constituents of phloem? Phloem is composed of four main elements: + Sieve tubes + Companion cells + Phloem parenchyma + Phloem fibres Class 9 Biology | Chapter 2 | NCERT Solutions & Notes 
