What evolutionary changes in stems lead to an increase in a plants capacity for producing energy for ...

Answer to q. 1

Leaves. Leaves with greater and greater area, with a greater number of stomata, maximize carbon gain
through photosynthesis. This originally occurred when some stems became modified into leaf-like
structures and eventually leaves. A branching pattern emerged with the branches becoming modified
into veins resulting in the space between veins becoming photosynthetic. The number of leaf veins in
more ancient species is 10 times fewer than in earlier evolving species. The most successful plant
group, angiosperms, has large leaves with many stomata and a dense system of veins

Answer to q. 2

T

Extremely helpful

Cool, thanks for the positive feedback