BIOL 1202 Study Guide - Sporangium, Megaspore, Gametophyte
Document Summary
Chapter 30: plant diversity ii the evolution of seed plants. Concept 30. 1: the reduced gametophytes of seed plants are protected in ovules and pollen grains. Characteristics common to all seed plants: seeds, reduced gametophytes, heterospory, ovules, pollen. Gametophyte/sporophyte relationships: gametophytes of seed plants develop within the walls of spores retained within tissues of the parent sporophyte, no longer dependent on water for fertilization. Ovules and production of eggs: an ovule consists of a megasporangium, megaspore, and protective integuments. Pollen and production of sperm: microspores develop into pollen grains, contain male gametophyte, pollen can be dispersed by air or animals, eliminates the need for water in fertilization. It gives rise to a pollen tube that discharges sperm into the female gametophyte within the ovule: see second part to figure 30. 3. A seed: develops from the whole ovule. 2: see third part to figure 30. 3. Concept 30. 2: gymnosperms bear naked seeds, typically on cones.
