A textbook states, 'Each plant tissue performs only one specific function'. What questions would you ask to critically examine the correctness of this statement? What examples of tissues would you take to find out the answers to these questions?
To critically examine the statement that each plant tissue performs only one specific function, I would ask the following questions: Can a single plant tissue perform multiple functions simultaneously, such as both protection and preventing water loss? Do complex permanent tissues perform functions beyond just conduction, like storage or support?
To find answers, I would take the example of epidermis, which is a protective tissue. It protects plants from mechanical injury, harmful microorganisms, and extreme environmental conditions. Simultaneously, it reduces water loss. This clearly shows that a single tissue can perform more than one specific function.
Another example I would examine is phloem, a complex permanent tissue. While its main function is to transport food, its phloem parenchyma stores food materials, resin, tannins, and latex. Additionally, phloem fibres, which are primarily schlerenchymatous, provide strength and support to the sieve tubes.
Thus, the given statement is not entirely correct. Examples of epidermis and phloem prove that plant tissues can perform multiple functions rather than just one specific function.
Explanation
The textbook context highlights that plant tissues can perform multiple functions. For instance, the epidermis acts as a protective tissue but also reduces water loss. Similarly, phloem is a complex permanent tissue responsible for food transport, but it also contains phloem parenchyma for storage and phloem fibres for support. These examples directly contradict the statement that each plant tissue performs only one specific function, allowing students to critically evaluate the claim.
Solution Steps
Step 1: Formulate critical questions challenging the 'one tissue, one function' idea, specifically asking if tissues can multi-task (e.g., protect and prevent water loss, or conduct and store).
Step 2: Provide the example of Epidermis (protective tissue), noting it both protects from injury/microorganisms/extreme conditions AND reduces water loss.
Step 3: Provide the example of Phloem (complex permanent tissue), noting it transports food, while its phloem parenchyma stores food/resin/tannins/latex, and its phloem fibres provide strength/support.
Step 4: Conclude that the statement is incorrect because these examples demonstrate multiple functions per tissue.