Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Chapter 4 Anatomy of Plants
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Plant Architecture Hierarchy Biochemicals Cells Tissues Organs
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Two Types of Plant Cells Prokaryote—cell without nucleus –genetic material (single circular DNA) contained in cytoplasm Eukaryote—cell with nucleus –genetic material (multiple chromosomes) surrounded by membrane
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Chemical Composition of Eukaryotic Cells 90% fluid (cytoplasm): free amino acids, proteins, glucose, other molecules Elements: 59% hydrogen, 24% oxygen, 11% carbon, 4% nitrogen, 2% other Molecules: 50% protein, 15% nucleic acid, 15% carbohydrates, 10% lipids, 10% other
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.
Cell Structures Cell wall Plasma membrane Protoplasts Organelles—plastids, mitochondria, microfilaments, endoplasmic reticulum, nucleus, vesicles, vacuole, Golgi body
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cell Parts Cell walls—primary ones made of hemicellulose; some cells have thickening of primary cell wall to add stability Plasma membrane—also known as plasmolemma or cytoplasmic membrane; made of phospholipids
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cell Parts (continued) Protoplast—inside of cell or cellular contents Cytoplasm—liquid matrix of protoplast –water solutes, proteins, and the like, that stream through protoplast
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cell Parts (continued) Organelles—internal structures –Plastids leucoplasts: store oil, starch, proteins cloroplasts: double-membrane plastids with chlorophyll used in photosynthesis in addition to storing starch and containing genetic information
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Other Organelles Mitochondria—convert foods into usable energy through aerobic respiration Nucleus—contains chromosomes, which are long strands of DNA Vacuole—storage reservoir for water, sugars, salt, and other biochemicals Endoplasmic reticulum—protein synthesis
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Other Organelles (continued) Ribosomes—where RNA goes for translation into proteins Golgi apparatus—important for glycosylation and secretion Peroxisomes—use oxygen to carry out catabolic reactions Microtubules—make up centrioles/cilia
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Tissues Meristems—contain actively dividing cells that form new tissues –Four types are apical, subapical, intercalary, lateral/cambial Permanent—may be simple or complex –Complex tissues include two types of conductive tissues: xylem and phloem
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Xylem and Phloem Xylem—conducts H 2 O/dissolved nutrients, amino acids, proteins, remobilized sugars from roots to aerial plant parts Phloem—conducts soluble sugars and metabolites such as proteins, hormones, dissolved minerals, salts from leaves to other plant parts
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.
Types of Cells in Xylems and Phloems Xylems—vessels, tracheids, fibers, and parenchyma cells Phloems—sieve tube cells, companion cells, phloem parenchyma, and phloem fibers
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Plant Tissues Roots—taproot or similar-sized branches, root hairs, cortex (wall), center (stele) Stems—supported by xylem (transports water/minerals); phloem transports manufactured food Leaves—stomata take in CO 2 /release O 2, photosynthesis mostly in palisade cells
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Primary and Secondary Growth Primary—takes place in young, herbaceous organs, resulting in increase in length of shoots and leaves Secondary—results in increased girth as layers of woody tissue are laid down