Day 1, 2
Day 1, 2. After the bean has been planted, the bean slowly absorbs water. The seed coat swells and may begin to slip off (Figs. 7, 8). Often it takes days, if ever, for the seed coat to completely fall off.
Figure 7. Hilum and bean seed coat. Bean hilum (star) and swollen seed coat. Magnified 24 times. Credit: E.T. Paparozzi
Figure 8. Bean seed coat expansion. The seed coat (arrow) expands and then continues to adhere to the cotyledons as it grows. Magnified 12 times. Credit: E.T. Paparozzi
Inside the swollen bean, the embryo of the bean plant has distinct parts.
Figure 9. Parts of the embryo inside the bean seed. The embryo consists of unifoliate leaves (arrow) and the root (two stars). Note: the cotyledons (star) are still attached below the unifoliate leaves. Magnified 12 times. Credit: E.T. Paparozzi
Figure 10. Close-up of embryo and bean seed coat. Another view of the parts of the embryo within the seed coat. Magnified 12 times. Credit: E.T. Paparozzi