BIOL 111 Lecture Notes - Gametophyte, Epicotyl, Gamete

• School: McGill University
• Department: Biology (Sci)
• Course: BIOL 111
• Professor: Irene Gregory- Eaves

Document Summary

Growth: quantitative irreversible increase in any cell parameters (eg. height, volume, weight, number in populations, etc ) Development: qualitative changes in body structure or function at certain stages of life cycle (eg. development of organs [organogensis], achieving final shape. Growth and development (size and shape) regulated by hormones: absicic acid: stress hormone, auxins: promotes stem elogation, brassinosteroids: related to steroid hormones in mammals, cytokinins: cell devision, ethylene: fruit ripening, gibberellins: seed germination. Growth graph: (number of cell per ml) vs time s shape graph. Small population, logarithmic growth, stationary phase (stable population) Tropic growth movements: shoot tips show positive phototropic growth. Cell on its side: gravity pulls auxins to the bottom side = more growth, growth of cells at bottom force plant to bend upwards. Toxic to roots inhibits root growth, root will grow opposite way than stem will grow, cells exposed to auxin will grow less so root will bend towards cells with auxin.