#6: They're a little difficult to see, but this clump of moss has growing on it little sporophytes! These diploid (with both sets of chromosomes) structures will, through meiosis, release haploid spores which will form a gametophyte (the green part of the moss from which the sporophytes are sprouting). Through mitosis, the gametophyte will produce gametes and the process will begin over again.
#7: I apologize for the grossness! My skin is an example of stratified (layered) epithelial tissue. That nasty gash is a result of a dance move gone wrong in rehearsal, but it also serves as an example of homeostasis: the formation of platelets to help heal a wound is a positive feedback reaction, meant to keep my body within a certain range of conditions.
#8: This is the auxin-producing area of a plant. When a new bud forms, a concentration of hormones (auxin) helps it develop and drives the developing behavior of the new plant.
#9: This is the cuticle layer of a plant. This waxy overcoat helps prevent that plant from dehydrating on hot days and serves as a barrier to unwanted particles. Also, stomata, found on this layer, regulate gas exchange.
#10: This lichen almost completely covers a tree in my front yard. It doesn't seem to be harming the tree, so the relationship is most likely an example of commensalism (I ruled out parasitism, because lichen can live on its own on a bare rock).
1 comment:
Those are the cutest little sporophytes ever! And I hope your platelets are doing their job and your body is back in homeostatic balance! :) Yikes!
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