BIOA02H3 Lecture Notes - Lecture 6: Seed, Apical Dominance, Ovule

• School: UTSC
• Department: Biological Sciences
• Course: BIOA02H3
• Professor: Ivana Stehlik

Document Summary

Bioa02h3 lecture 6: from seed to tree i. From seed to tree: seed to germination. Germination: from primary to secondary plant body, body plans of major angiosperm groups. Problem: without seed dispersal adaptations, most seeds are deposited close to mother plant, parent-offspring competition for space, mating btw. Different dispersal agents: explosive self-dispersal diy, wind dispersal, water dispersal, external hitchhiking. Gravity-dispersed seed vs. small mammals: starch-rich, oil-rich = great food, seed catching, some caches: forgotten = tree seedling recruitment. Seed anatomy (angiosperms): contains plant embryo, covered with protective seed coat, embryo: embryonic shoot, root (radicle) & cotyledons (embryonic leaves, food for embryo (endosperm) Food for the embryo: endosperm: endosperm: food storage cells inside seed; not part of embryo; developed through. Double fertilization df: df (angiosperms only): parallel to fertilization of egg by pollen (=embryo), one pollen nucleus (1n) fertilizes central cell" (2n) inside ovule = endosperm (3n)