Question

During the discussion in class, Rohan gives a statement that, “A tissue is a group of similar cells performing similar functions”. But Rajiv counter argues that, “this is true in case of simple tissues but little different in case of complex tissues”. Provide your explanation in view of the discussion in class.

Answer 1

Rohan’s statement is correct in the case of simple permanent tissues. These tissues, such as parenchyma, collenchyma, and sclerenchyma, consist of only one kind of cell, and all the cells are structurally similar and perform the same function.

Rajiv is also correct regarding complex permanent tissues. These tissues, such as xylem and phloem, are composed of more than one type of cell.

For instance, xylem includes tracheids, vessels, xylem parenchyma, and xylem fibres, while phloem contains sieve tubes, companion cells, phloem parenchyma, and phloem fibres. Although these cells differ in structure and function, they work together as a single unit to perform a common role, transport of water in xylem and transport of food in phloem.