AP BIOLOGY

Detailed explanation-1: -The inner soft bark, or bast, is produced by the vascular cambium; it consists of secondary phloem tissue whose innermost layer conveys food from the leaves to the rest of the plant. The outer bark, which is mostly dead tissue, is the product of the cork cambium (phellogen).

Detailed explanation-2: -B: The inner bark, or “phloem”, is pipeline through which food is passed to the rest of the tree. It lives for only a short time, then dies and turns to cork to become part of the protective outer bark.

Detailed explanation-3: -Answer and Explanation: Bark is composed of secondary phloem and the periderm. Xylem is a component of wood. Bark is the outermost layer in woody plants that is composed of the stems and the roots.

Detailed explanation-4: -Cells having secondary cell walls are incapable of expanding and dividing therefore upon maturity they are dead. Hence Phloem fibres and Sclereids are both dead cells of phloem.

Detailed explanation-5: -The outer bark is composed of secondary xylem whereas the inner bark contains secondary phloem. The inner bark assimilates dead tissues and the outer bark sloughs off dead tissues.