Heartwood and sapwood consist of a. bark. b. periderm. c. secondary xylem. d. secondary phloem.

Verified step by step guidance

1. Identify the tissues involved: Heartwood and sapwood are terms related to the internal parts of a tree trunk or branch, specifically within the wood.
2. Understand the role of each option: Bark and periderm are external tissues, while secondary xylem and secondary phloem are internal tissues involved in transport.
3. Recall the composition of wood: Wood primarily consists of secondary xylem, which is responsible for water transport and structural support.
4. Relate the terms to the correct option: Heartwood and sapwood are both made up of secondary xylem. Heartwood is the older, non-functional central wood, and sapwood is the younger, functional outer wood.
5. Choose the correct answer: The correct answer is c. secondary xylem.

Key Concepts

Heartwood and Sapwood

Heartwood and sapwood are two types of secondary xylem found in trees. Sapwood is the younger, outer layer that actively participates in water transport and nutrient storage, while heartwood is the older, inner layer that no longer conducts water but provides structural support.

Secondary Xylem

Secondary xylem is produced by the vascular cambium and is responsible for the transport of water and minerals from the roots to the leaves. It consists of both heartwood and sapwood, and its growth contributes to the increase in the diameter of the tree trunk over time.

Bark and Periderm

Bark refers to the outer protective layer of a tree, which includes the periderm and secondary phloem. The periderm is a protective tissue that replaces the epidermis in older stems and roots, while secondary phloem is involved in the transport of nutrients, primarily sugars, throughout the plant.