The radiation from the sun
Blood plasma transports nutrients, waste (like uric acid, creatinine, and ammonium salts), albumin (protein), and electrolytes.
White blood cells, nerve cells, bone cells, and *striated* muscle cells
One should consider: proper clothing and shoes-so not to get injured. Knowledge of equipment and activity—one should know how to use all equipment and know how to play the games/activity so not to hurt themselves or others. Proper hydration and nutrition before hand-so not to get dehydrated or dizzy or sick and safety og equipment and location-check for broken items and discard, check environment for hills, holes, sticks, traffic, etc.
