2. Metabolic waste in blood is filtered out by human urinary system, and digestive waste is discharged by human digestive system.
The chameleon changes the skin color according to the environmental color, and human skin will get goose bumps in a cold environment.
4. Birds hatch and grow up from eggs, then mate and lay eggs, angiosperms germinate and grow, pollen is fertilized to produce seeds, and seeds germinate.
5. No pains, no gains. Children are similar in appearance and height to their parents, but not exactly the same. Similarity represents heredity, and dissimilarity represents variation.