Letâs look at ferns as an example of alternation of generations. The fern plants you see out in the woods, or in a garden, or by a river are sporophytes. They produce spores. If you turn over a fern frond (thatâs just a fancy word for leaf), sometimes youâll see little circles all over the underside of the leaf.
Tricyclic Antidepressant (TCA) Overdose. California Poison Control 1-800-876-4766. Pediatric considerations. Low toxicity threshold of TCAs. Therapeutic doses range from 2-4 mg/kg/d. Toxicity is observed at doses of 10-20 mg/kg. Ingestion of only two 50-mg tablets in a 10-kg toddler can be sufficient. to produce symptoms of toxicity.
Vitamin toxicity is a condition in which a person develops symptoms as side effects from taking massive doses of vitamins. Vitamins vary in the amounts that are required to cause toxicity and in the specific symptoms that result.he exceptions are severe vitamin D toxicity, severe vitamin A toxicity, and severe vitamin B 6 toxicity. Too much vitamin D leads to deposits of calcium salts in the soft tissue of the body, which cannot be reversed. Birth defects due to vitamin A toxicity cannot be reversed.