Example of otherwise male cotton ball worm can be attracted to female tobacco

Example of otherwise male cotton ball worm can be

This preview shows page 21 - 23 out of 47 pages.

Example of otherwise: male cotton-ball worm can be attracted to female tobacco worms. Since the genitalia does not match, they get stuck and die. This works on a small scale only. o Usually emitted by the female o Also a directing signal o They follow pheromones (directing) o Pheromone traps: Mediterranian fruit flies (1 female up to 800 offspring). This caused problems for citrus fruits in California. They used traps and sterile mates, but it did not work and they had to resort to spraying. Traps: release the pheromone, and the males (who have longer antennae) either get stuck in the traps or exhaust themselves looking for the females. Pheromone for the gypsy moth = ―displature‖ o Androestenol = ―musky‖ ―Organic‖ Foods: $5.6 billion industry They do not contain SYNTHETIC pesticides. But natural pesticides can cause just as many problems. Also, the organic foods are still susceptible to contamination: o Spinach and E. coli O157:H7. o Peanuts and Salmonella . Industrial Agriculture: Food is produced on a large scale in the Western World. In 1860, 68% of the population was working in farming. In 1990, 38% in North America. Today in Canada it is around 2%. This is the price we pay for having cheap food. % of income going to food: o Canada = 10% o Mexico = 25% o India = 50% Still, there are 20-80 million cases of food poisoning, and 5000-10000 deaths. 70% of antibiotics used in animal feed. The bacteria can become resistant.
Image of page 21
Obesity causes 300,000 deaths. The problem with food in North America is that there is too much of it. Even most cereals are more than 50% sugar. ADVERSE FOOD REACTIONS Perceived risk: Robert Gibbon Johnson (lawyer)- 1890 o Ate a tomato, even though people in North America thought it was poisonous (because it was in the same family as the Belladonna plant, whose seeds and berries were toxic). o On that day, the American tomato industry was born At the time, there were a lot of real risks: Gooseberries had copper added to them to make them look green. Chalk was added to watered down milk, arsenic and boric acid was sprinkled on meat and fish to reduce spoilage and lard was added to ―extend‖ butter. Plaster of Paris was added to flour, arsenic oxide was added to meat (it killed microbes that turned meat black), Indigo was added to tea to extend it. There were no laws at all. Pesticide regulation: The amount of residues allowed is carefully regulated. The FDA does regular checks on a random- sampling basis. But there are still the possibilities of accidents: o Cucumbers are treated with a pesticide called Aldicarb, an acetylcholinesterase inhibitor (normally breaks down acetylcholine). Too much ActCh leads to cholinergic stimulation, which can kill. Insects use ActCh, and you can kill them. But at the wrong dose you can kill people too.
Image of page 22

Want to read all 47 pages?

Image of page 23

Want to read all 47 pages?

You've reached the end of your free preview.

Want to read all 47 pages?

  • Spring '11
  • Multiple
  • Chemistry

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture