This is an important issue for gardeners with children and pets. Its good information to be familiar with. I noted as I searched for websites that listed common poisonous plants that more attention has gone into providing this information to pet owners than to people caring for children.
That garden is a good idea. Somehow photographs and drawings just aren't good enough for identifying a plant in person. I have flower books with both in them, and it is still difficult to identify a plant. Did not know that apple seeds were poisonous. Though never thought to eat one.
They are poisonous, but not very strongly - you'd have to eat something like a hundred in one sitting to be poisoned. They taste a bit like bitter almonds.
In effect, yes. They contain cyanogenetic glycosides, which are chemicals that break down to produce cyanide on being chewed and digested
