19. Lee las siguientes afirmaciones y reescríbelas correctamente:

a. El cigoto es una estructura pluricelular formada por dos células, una masculina y otra femenina.

b. La zoocoria es una forma de transporte activo del polen realizada por los animales.

20. Describe los dos principales tipos de polinización cruzada.

21. ¿Qué estructuras encontramos en las gimnospermas sustituyendo al fruto? Razona qué parte de la flor seguramente no presenta este grupo de plantas.

22. Fíjate en las características de un melocotón e indica qué tipo de dispersión de las semillas crees que presenta.

Gametophyte Stage and Sporophyte Stage: Plants have two main stages in their lifecycle - the gametophyte stage where male and female gametes are produced, and the sporophyte stage which develops from the zygote. In angiosperms, male gametophytes develop in the microsporangium and female gametophytes in the megasporangium.

Types of Pollination: The two primary types of cross-pollination are self-incompatibility, where a plant's stigma rejects its own pollen, and dichogamy, where the male and female reproductive organs mature at different times to prevent self-pollination.

Gymnosperms and Fruit Substitution: Gymnosperms replace fruits with structures like cones or seeds. They lack structures like fruits as gymnosperms do not undergo the process of double fertilization seen in angiosperms.

Learn more about Plant Reproduction here:

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