Identify target species of insects fungi or weed use proper pesticides 80 of

Identify target species of insects fungi or weed use

This preview shows page 7 - 11 out of 54 pages.

Identify target species of insects, fungi or weed & use proper pesticides 80% of fresh fruit & veggies that we eat are residue free o But qualifier: depends on how carefully you look (parts per trillion?! At that level, everything is contaminated by everything) Processed foods: 90% residue free
Image of page 7
° ° REASON #2 More nutritious?? Nutrition level does not depend on organic/conventional method of growing Depends on the variety of the seed, fertilizer, crop rotation, sun exposure, rain amount, time of harvest, transportation, temperature control ° ° REASON #3 Organic = less pesticide wastes? o QUALIFIER o Examples with study done with soybeans grown conventionally VS organically Problem with large farming of soybeans: aphids Natural predators not effective since land is so large Study saw the impact on aphids using different pesticides Used environmental impact quotient Looks at the parameters that concern us when we use pesticides Does it go through the skin? Effect wildlife? Leeching? Runoff? Human health concerns? Found that organic mineral oil had the poorest record ° Organic better than conventional? o Not always, case-by-case scenario No SAFE substances, only SAFE WAYS to use substances ° ° Lesson 2 (Agricultural Science 2) : Assyrian relief (870 BC)
Image of page 8
o Artificial pollination of a date palm with pollen taken from another palm o Grapefruit: hybrid of orange & pomelo o Triticale: consequence of (probably) accidental cross pollination Hybrid of wheat & rye o CROSS POLLINATION Modern science: o Made it possible to take seeds & expose then to chemicals/radiation to mutate it (change DNA) o Laborious process Today: o Gene splicing Genes are fragments of DNA that code for specific proteins Possible to take one piece & snip it out & put it into the DNA of another organism Recombinant DNA technology Chymosin o Enzyme used in making of cheese o Curdles milk when added to it o Traditionally, came from calves’ stomach Extract of the stomach: rennet o Scientists discovered that particular gene that is used to form chymosin Can be extracted form calves’ cells o DNA of the calf isolated, fragment taken, put into yeast cell. Yeast cell now churns out chymosin 1994, the first real food product of GM was introduced o Used a tomato o Tomatoes are not year-round crops
Image of page 9
When the season is not right, they get shipped when they are green & the gassed with ethylene to ripen them Possibility to make them year-round by inhibiting an enzyme called polygalacturonase which breaks down pectin which is responsible for tomato’s texture Idea is that tomatoes don’t get mushy when being transported already ripe Did not change the taste (most people have issues with GMO because they don’t really see the benefit of the technology) Original Flavr Savr tomato did not taste any better so it sort of disappeared o Aroused anti-genetic food movement Claim they were UN tested, UN labeled & Un predictable All claims false
Image of page 10
Image of page 11

You've reached the end of your free preview.

Want to read all 54 pages?

  • Spring '10
  • Multiple
  • E number, Food additive

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

Stuck? We have tutors online 24/7 who can help you get unstuck.
A+ icon
Ask Expert Tutors You can ask You can ask You can ask (will expire )
Answers in as fast as 15 minutes