L2 Plant & Animal Reproduction Process

• Sexual Reproduction (Plants): involves the fusion of male and female gametes.
• Sexual Reproduction in Plants: Pollination, Fertilization, and Seed Formation
• Pollination: the transfer of pollen from the male reproductive organ (anther) to the female reproductive organ (stigma)
• Pollination: It can occur through various agents such as wind, water, or animals.
• Fertilization: after pollination, the pollen grain germinates on the stigma ang grows a pollen tube.
• Fertilization (cont.): this tube carries the male gametes (sperm cells) to the ovary, where this takes place. This leads to the embryo.
• Seed Formation: the fertilized ovule develops into a seed, which contains the embryo, endosperm, and protective seed coat.
• Seed Formation (cont.): the is dispersed and can germinate under favorable conditions, giving rise to a new plant.
• Asexual Reproduction (Plants): does not involve the fusion of gametes and produces offspring that are genetically identical to the parent plant.
• Methods of Asexual Reproduction: Vegetative Propagation, Budding, and Fragmentation
• Vegetative Propagation: involves the production of new plants from vegetative parts such as stems, roots, or leaves.
• Vegetative Propagation: examples include runner in strawberries, tubers in potatoes, and bulbs in onions.
• Budding: the formation of a small outgrowth (bud) on the parent plant, which eventually develops into a new individual.\
• Budding: examples include yeast and hydra
• Fragmentation: occurs when a parent plant breaks into fragments, and each fragment can grow into a new plant.
• Fragmentation: commonly observed in ferns and mosses
• Sexual Reproduction (Animals): involves the fusion of male and female gametes, similar to plants.
• Key Steps in Sexual Reproduction (Animals): Mating, Fertilization, Embryonic Development, and Live Birth or Egg Laying
• Mating: Animals engage in mating behaviors to bring the male and female reproductive organs in close proximity.
• Mating: This can involve courtship rituals, displays, or physical contact
• Fertilization: during mating, the male transfers into the female's reproductive tract.
• Fertilization: occurs when a sperm cell fuses with an egg cell, forming a zygote.
• Embryonic Development: The zygote undergoes cell division and develops into an embryo.
• Embryonic Development: the embryo may develop inside the female's body (internal fertilization) or outside (external fertilization), depending on the species.
• Live Birth or Egg Laying: Live birth is common in mammals, while egg laying is observed in reptiles, birds, and some fish.
• Methods of Asexual Reproduction (Animals): Budding and Parthenogenesis
• Budding (Animal): A small bud grows on the parent organism and eventually detaches to become a new individual.
• Budding (Animal): some invertebrates like corals and jellyfish can reproduce through this.
• Parthenogenesis: a form of asexual reproduction where an unfertilized egg develops into an embryo.
• Parthenogenesis: is observed in certain reptiles, insects, and fish