BIOL 111 Lecture 6: BIOL 111 – Lecture 6 – Plant Body_ Primary & Secondary Structure

• School: McGill University
• Department: Biology
• Course: BIOL 111
• Professor: Rudiger Krahe

Document Summary

Biol 111 lecture 6 plant body: primary & secondary structure. Lecture date/time: sept 29th, 2015 / 10:35-11:25 am. Root system: roots and root branches & any modifications of roots. Shoot system: main stem, branches, leaves, flowers & any modifications of those parts. Axillary part grows into a branch/ flowering plant or a leaf. Leaves can be spirally, or alternating, determined by the species and fibonacci numbers (each number is the sum of the previous two numbers) flower and leaf arrangements are determined according to fibonacci numbers. Apical bud = where growth is occurring. Taproot system: one main root that goes deep, from which all the stems grow; one main thickest root, branches are thinner. Simple leaves: one single blade & a petiole (the stem part of the leaf) Compound leaves: leaflets arranged along a central axis, doubly compound leaf: further division of the axis. Leaf area should be maximized to maximize photosynthesis & contact to light.