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 9 green seeds DHJanzen100318.jpg high resolution
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| Photosynthesis does not always begin in the green seedling. This cross section through a Bauhinia ungulata pod (Fabaceae) shows unambiguously what every child knows who does not like green peas. But when the Bauhinia seeds are mature and being dispersed, they are rock hard and non-green, just like the carob seed in DHJanzen100317.jpg above. In short, while dormant seeds are generally non-photosynthetic, many growing seeds have what appears to be functional chlorophyll in plastids in physiologically active seeds (plastids that then become inactive in the dormant mature seed, something that chloroplasts are not supposed to be able to do). Recall that the seed contents, the embryo and its cotyledons, are a different plant from the mother. This means that the kid has the opportunity to partly create his/her own bank account instead of being totally dependent on the mother, and we all know what that can mean. I will not dwell on it, but there is even a bizzare mediation board between the kid and the mother, made up of more gene sets from the mother than the father, that transmits all messages and all resources between the offspring and mother. | ||
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