Question

When did C4 grasses first appear?

Answer 1

C4 fixation:

1. The C4 or carbon-four fixation is a form of carbon fixation whereby the first stable product (oxaloacetic acid) is a four-carbon compound.
2. C4 photosynthesis in grasses is speculated to have evolved between 24-35 million years ago.
3. C4 plants include Maize and Sorghum.
4. They have a typical Kranz anatomy which includes a wreath of bundle sheath cells surrounding mesophyll cells.