BIOL 1902 Lecture Notes - Lecture 13: Sodium Chloride, Retina, Abies Balsamea

• School: Carleton University
• Department: Biology
• Course: BIOL 1902
• Professor: Michael Runtz

Document Summary

Plants also have chemical defences to overcome: some herbivores sequester the toxins. Too many toxins, even in a milkweed plant for a monarch caterpillar, will cause it harm. Sometimes the saliva of the insects can neutralize the toxins. Some insects employ a vein drain strategy to cut off the flow of toxins i(cid:374) the pla(cid:374)t"s lea(cid:448)es (cid:894)(cid:272)utti(cid:374)g the (cid:448)ei(cid:374)s (cid:894)phloe(cid:373)(cid:895)(cid:895): some use enzymes to counter the toxins. Mfo"s (cid:894)mi(cid:454)ed fu(cid:374)(cid:272)tio(cid:374) o(cid:454)idases(cid:895) are t(cid:455)pes of e(cid:374)z(cid:455)(cid:373)es that a(cid:374)i(cid:373)als produ(cid:272)e that help neutralize the toxins once the animal ingests them. Some herbivores are specialists, eating only one or two kinds of food: red-headed pine sawflies eat pine needles (not spruce needles, etc. ) Others are generalists: beavers eat a large variety of foods. Some animals switch foods for a more balanced diet: moose for example: Fresh leaves and twigs (high carbohydrates, protein, low sodium) during the summer. Balsam fir (very low sodium) during the winter.