All characteristics of life rely on the sun.
George is lifting weights. He starts by doing biceps curls
which involves flexing his
elbows. His elbow is able to bend
because the humero-ulnar joint is a hinge
joint. Sam is doing leg presses, extending his knees as he pushes
against the weights. Meanwhile, Jane is doing "lat pulls" by pulling
downward on a weighted bar. This movement involves adduction of her arms.
Her shoulder joint is a ball-and-socket joint, allowing
a wide range of movements.
Adaptions to collect and retain water - thick, non-pourous stems, not leaves, but thick lobes and the ability to store water until its needed.