In this Grade 7 Life Science lesson from Chapter 11: Plants, students learn how seeds and pollen function as reproductive adaptations that give seed plants survival advantages over spore-producing plants like mosses and ferns. The lesson covers key concepts including seed structure, embryo development, germination, pollination, and how pollen grains protect and transport sperm cells. Students also compare the characteristics of seeds and spores to understand why seed plants are so widespread across diverse environments.
Section 1
Seeds Protect Embryos Until Conditions Are Right
Seeds contain plant embryos with protective coatings and nutrients. Unlike single-celled spores, seeds can remain dormant for years until moisture, temperature, and conditions trigger germination.
Section 2
Pollen Delivers Sperm Without Water
Pollen grains transport sperm cells to female parts of plants without needing water. With hard outer coverings, pollen can be carried by wind, water, or animals to complete fertilization.
Section 3
Gymnosperms Produce Seeds Without Fruit
Gymnosperms like pine trees, cycads, gnetophytes, and ginkgoes have reproduced with "naked seeds" for over 250 million years. Their adaptations help them survive in dry, cool environments.
Section 4
Pinecones Release Seeds Through Environmental Triggers
Pinecones open and close in response to environmental conditions. When dry, scales separate to release winged seeds; when wet, they close to protect developing seeds inside.
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Section 1
Seeds Protect Embryos Until Conditions Are Right
Seeds contain plant embryos with protective coatings and nutrients. Unlike single-celled spores, seeds can remain dormant for years until moisture, temperature, and conditions trigger germination.
Section 2
Pollen Delivers Sperm Without Water
Pollen grains transport sperm cells to female parts of plants without needing water. With hard outer coverings, pollen can be carried by wind, water, or animals to complete fertilization.
Section 3
Gymnosperms Produce Seeds Without Fruit
Gymnosperms like pine trees, cycads, gnetophytes, and ginkgoes have reproduced with "naked seeds" for over 250 million years. Their adaptations help them survive in dry, cool environments.
Section 4
Pinecones Release Seeds Through Environmental Triggers
Pinecones open and close in response to environmental conditions. When dry, scales separate to release winged seeds; when wet, they close to protect developing seeds inside.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter