lec 6

Question 1

what is a landrace? what distinguishes them from the wild progenitor? what about regular degular consumption corn?

Answer 1

a population that is genetically heterogenous, that is well adapted to the ecogeographic area incl edaphic and climatic conditions

the wild progenitor, also a product of natural selection, differs from landraces in that landraces are cultivated while the wild progenitor is completely wild

landraces are not consumption corn - they are morphologically different

Question 2

is corn a monocot or a dicot? fuck it list the traits too
- leaf veins
- root structures
- vascular bundles

Answer 2

monocot

• parallel leaf veins
• fibrous root structure
• scattered vascular bundles

Question 3

what was corn domesticated from? what traits had to be selected for for us to get corn?

Answer 3

corn was domesticated from teosinte, a wild grass
- became less branched
- grew fewer ears
- became non-shattering
- weak dormancy
this got us maize

then from maize to corn was bigger ears, larger seeds, and larger plant size

Question 4

corn is not sustainable in the wild. why?

Answer 4

N requirements are higher than realistic, so N inputs are necessary for corn to survive
[put a pause on this one]

Question 5

where did corn domestication first start?

Answer 5

began in mexican highlands (balsas valley), where it then spread to north and south america

Question 6

corn was the foundation for which three civilizations?

Answer 6

mayans, incans, and aztecs

Question 7

the corn plant is monoecious. what does this mean, and how does corn exhibit it?

Answer 7

male and female parts are on the same plant, but in separate areas

for corn, pollen producing tassels are at the top, while silks in the ear collect pollen and transfer them down the pollen tube to be fertilize

Question 8

corn has two types of roots. what are they?

Answer 8

thinner shallow roots for getting nutrients etc, thicker brace roots for stability

Question 9

how is corn pollinated?

Answer 9

wind

Question 10

corn can make hybrids. how so?

Answer 10

1. get two inbred lines (most of the genes on the chromosome are the same)
2. mix! its that simple
   the F1 is the first generation after the mixing occurs, which has traits of both inbred parents

in corn this is actually a really efficient method of isolating traits and passing them down

Question 11

one may say that “corn is that bitch.” what makes her, in this sense, “that bitch?”

Answer 11

• seeds + plant are very large
• one seed is planted at a time, rather than scattering (efficient)
• ears are on the side of the stalk rather than the top (efficient collection)
• corn is cross pollinated, compared to other cereals which are self pollinated (diversity)
• C4 metabolism (highly productive - better than C3 photosynth)

Question 12

who are the largest producers of corn?

Answer 12

US and China

in general grown in temperate climates, also incl brazil, india, south africa, and europe

Question 13

how is corn used?

Answer 13

• corn flour, corn flakes, corn starch, etc
• biofuels
• animal feed (for ruminants)

Question 14

idk if itll come up but what order + family is corn in

Answer 14

poales, poaceae (just like wheat + barley)