01:119:100 Lecture Notes - Lecture 21: Guard Cell, Xylem, Eudicots

• School: Rutgers University
• Department: Biological Science
• Course: 01:119:100
• Professor: Keating

Document Summary

Covered by cuticle (waxy layer) reduces water loss, doesn"t allow for gas exchange: stomata allows for gas exchange. More stomata found on lower surface of leaf. Open during day & closed at night/during drought. Comprised of parenchyma cells (contain chloroplasts) & loosely arranged: allows for gas exchange. Xylem found in bundle toward upper epidermis. Phloem found in bundle toward lower epidermis. Continuous w/ xylem & phloem of stem (and root: eudicot vs. monocot leaves, eudicot. Pediole stalk that attaches blade to stem. Separate palisade & spongy mesophyll layers: monocots. Lack pediole & instead base of leaf wraps around stem. Location where vascular tissue used to extend from stem to leaf: lenticle loosely arranged cells in bark of woody twigs. Allow gas exchange oxygen & other gasses diffuse through lenticles. Herbaceous eudicot: does not undergo secondary growth, only primary growth, dermal tissue aerial area so has cuticle. Consists of epidermis (covered with cuticle & stomata: ground tissue.