BIOL 111 Lecture Notes - Lecture 8: Gametophyte, Flowering Plant, Photoperiodism

• School: McGill University
• Department: Biology (Sci)
• Course: BIOL 111
• Professor: Rajinder Dhindsa

Document Summary

Biol 111-lecture 8-growth, development, reproduction, and response to environmental stresses: growth irreversible quantitative increase (height, volume, weight, etc, tropic growth growth in response to an unidirectional stimulus. Light & phototropism, auxin moves from the lighted side to shaded side and causes the plant to bend towards light. Gravity & geotropism, auxin moves to the lower side of the shoot, causes the shoot to grow upwards and roots do the opposite (negative geotropism in shoot, positive geotropism in roots) Apical dominance, higher auxin at the apex: development qualitative changes in body structure or function (organogenesis, morphogenesis, juvenile phase, sexual maturity, flowering, physiological aging, seed germination. -seeds are dormant just after being shed & won"t germinate until the hormone abscisic acid(aba) degrade. -sometimes seed coats has to be cracked or weakened to allow germination. -many small seed need light signal (ensure that they germinate near the surface of the soil: reproduction in angiosperms. -from modified stems, leaves, etc. e. g. potato, bryophyllum.