* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Atoms, Elements, Compounds and Mixtures
Survey
Document related concepts
Cell growth wikipedia , lookup
Extracellular matrix wikipedia , lookup
Endomembrane system wikipedia , lookup
Cytokinesis wikipedia , lookup
Cell nucleus wikipedia , lookup
Cell encapsulation wikipedia , lookup
Cell culture wikipedia , lookup
Programmed cell death wikipedia , lookup
Tissue engineering wikipedia , lookup
Cellular differentiation wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Transcript
Transport in Plants Spot the Difference! Transport in Plants • Xylem water and soluble minerals travel upwards • Phloem sugars travel up and down Section of a Plant Root xylem phloem • Xylem cells arranged in a cross shape • Phloem cells within the corners of the xylem Section of a Leaf • Vascular bundles form the midrib and veins of the leaf • Xylem above phloem Section of a Stem Vascular bundle xylem phloem cambium (in between the xylem and phloem) • Separate vascular bundles • Bundles towards outer edge of stem • Ring of vascular tissue around the edge of stem • Xylem towards inside and phloem towards outside of stem • Cambium - layer of meristem cells. Undifferentiated. Produce new xylem and phloem phloem phloem xylem cambium Function of Xylem • Transports water and minerals from roots to the rest of plant • Transported upwards Structure of Xylem • Tubes to carry water and dissolved minerals, fibres for support • Xylem vessel elements (living parenchyma cells) impregnated by lignin • Lignin waterproofs the cell walls and prevents them from collapsing. This leaves a long column of dead cells • Water can pass through the cell walls through pits • No cell contents, nucleus or cytoplasm Function of Phloem • Transports sugars from one part of plant to another • Transported up or down 2 types of cell – sieve tube elements – companion cells Linked by plasmodesmata Structure of Phloem Sieve tube element • Very little cytoplasm, no nucleus • Lined end to end forming a tube • Contains perforated cross-walls (sieve plates) – allows sap through the pores Companion cell • Large nucleus, dense cytoplasm, many mitochondria • Responsible for metabolic processes (requires ATP)