Chapter 23

Distinguish between the following: collenchyma cell and sclerenchyma cell; tracheid and vessel element; perforation plate and pit; sieve cell and sieve- tube element; callose and P-protein.

How do simple tissues differ from complex tissues? Give examples of each.

How do sclereids differ from fibers?

What is the developmental and/or functional relationship between a sieve-tube element and its companion cell(s)?

Explain the following: Tracheary elements undergo programmed cell death, but sieve elements undergo a selective breakdown.