BIO 1130 Lecture Notes - Lecture 4: Dioecy, Plant Reproductive Morphology, Sequential Hermaphroditism

• School: University of Ottawa
• Department: Biology
• Course: BIO 1130
• Professor: Gambarotta Sandro

Document Summary

Flower structure: perfect flowers (ex: lily, both stamens and carpels on same flower. Imperfect flowers: stamens or carpels, not both. Monoecious plant: male flowers and female flowers (staminate and pistilate flowers) on the same plant: ex: corn, top of stem is where they dispense pollen. Dioecious plant: some plants with only male flowers, some with only female flowers: ex: willows, ginko, holly. Flower structure: dichogamy, sequential hermaphroditism in a perfect flower, protandry: male phase comes before the female phase, protogyny: female phase comes before the male phase. Herkogamy: approach herkogamy (pin): stigmas are above the anthers, reverse herkogamy (thrum): stigmas are below the anthers, ex: herkogamy in primula. Pollen grains: meiosis produces haploid microspores, mitosis in microspore produces a pollen grain. Immature male gametophyte: one cell develops into two sperm cells, other cell produces pollen tube. Ovules: form inside carpel, on wall of ovary, micropyle opening at one end, meiosis produces produces four haploid megaspores.