Crop Plants:Why You Should Never Go Hungry

In The Beginning…• Life for humans was very different:

– No permanent settlements– No real specialization

• Hunt or Gather – Less stable food supplies

• Then, came mankind's greatest invention…

• AGRICULUTURE!• Why so fly (cool)?

– More food/ better control on supply– Permanent settlements– More free time to develop ideas– Specialized roles in society

Dominating the Market• Foods to feed the world…• What characteristics do they have?

– Easy to grow/grow fast– Lots of energy inside/carbs– Stay cheap

• Crop Plants:1) Cereal Crops grasses

– Rice common food– Wheat bread– Barley bread and beer– Sorghum and millet

2) Stems – Yams, taro, and potatoes

3) Some fruits – Dates and bananas

The Good and The Bad of Crops• What are the healthy benefits of crops?

– Carbohydrate heavy– Protein (not as much as meat)– Rich in Vitamin B– Lots of Ca2+ and Fe– Source of fiber to help peristalsis

• What is lacking from crops?– Proteins lack lysine (essential Amino Acid)– Little Vitamin A, C, or D

• How do we fix this?1) Eat balanced diet of fruits, vegetables,

meats, and dairy2) Modify genes of crop plants– Golden Rice vitamin A

Ancient Agricultural Secret• How long have “GM” foods been

around?– Since agriculture was created– Farmers have always tried mixing the

best of each crop to make best looking/tasting products

• What term is used for this process?– Cross pollination “outbreeding”

through genetically varied individuals– Genetic diversity = better chance of

adapting • Why are plants so easy to cross-

breed?– Additional chromosomes rarely

destabilize zygote ; polyploidy– Hybrid vigor

Pollination • What are males gametes in plants?

Where are they?– Pollen grains on anthers

• What are the females gametes in plants? Where are they?– Ovule inside the stigma

• Pollination mixing of pollen grains with stigma to cause fertilization

• What are the different methods of pollination?

1) Wind pollen designed to be carried by breeze

2) Pollinators pollen carried by birds, insects, etc…

Fertilization 1) Pollen lands on stigma and

chemical signals cause pollen tube to grow down style to the ovary

2) Pollen tube reaches the ovule and deposits 2 male gametes; Inside ovary are 6 haploid cells and 1 diploid nucleus

3) 1 male gamete fuses with 1 female gamete; this becomes the zygote (2n)

4) Second male gamete fuses with diploid endosperm nucleus; this becomes a 3n endosperm (food source for seed)