BIOL 1108 Chapter Notes - Chapter 29: Tracheid, Parenchyma, Phloem
Core Concepts
• The evolution of land plants from aquatic ancestors
introduced a major challenge for photosynthesis: How to get
enough carbon dioxide without drying out.
• Leaves have a waxy cuticle and stomata, both are important
in regulating carbon dioxide gain and water loss.
• Xylem allows vascular plants to replace water evaporated
from leaves with water pulled from the soil.
• Phloem transports carbohydrates to the non-photosynthetic
portions of the plant for use in growth and respiration.
• Roots expend energy to obtain nutrients from the soil.
Xylem is found on the inside of
vascular bundles.
Xylem is also a complex tissue
that has four cell types:
1. Tracheary elements-the
water conducting cells (two
types: tracheids and vessel
elements)
2. Parenchyma
3. Fibers
